JP4523149B2

JP4523149B2 - Heat exchanger

Info

Publication number: JP4523149B2
Application number: JP2000393031A
Authority: JP
Inventors: 正角田; 英海木村; 秀一山村; 哲矢小川
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2000-12-25
Filing date: 2000-12-25
Publication date: 2010-08-11
Anticipated expiration: 2020-12-25
Also published as: JP2002195768A

Description

【０００１】
【発明の属する技術分野】
本発明は、第１伝熱板および第２伝熱板を交互に重ね合わせ、両伝熱板間に低圧流体通路および高圧流体通路を交互に形成した熱交換器に関する。
【０００２】
【従来の技術】
高温流体が流れる流体通路と低温流体が流れる流体通路とを交互に配置して高温流体および低温流体間で熱交換を行う熱交換器は、例えば実開平３−７９０８２号公報、特表平５−５０６９１８号公報、米国特許第３８３１３７４号明細書により既に知られている。
【０００３】
上記実開平３−７９０８２号公報には、紙製の仕切り板を所定間隔で折り曲げることにより相互に平行に延びる多数の間隔保持部を突設し、複数の仕切り板をその間隔保持部が直交するように交互に重ね合わせたもので、隣接する仕切り板間に高温流体が流れる流体通路と低温流体が流れる流体通路とを交互に形成している。
【０００４】
また上記特表平５−５０６９１８号公報に記載されたものは、ガスタービンエンジンに用いられる円環状の熱交換器であって、同軸に配置されたアウターケーシングおよびインナーケーシング間にインボリュート曲線状に湾曲した多数の伝熱板を所定間隔を存して配置することにより、圧縮空気が通過する高圧通路と燃焼ガスが通過する低圧通路とを円周方向に交互に配置している。
【０００５】
また上記米国特許第３８３１３７４号明細書に記載されたものは、ガスタービンエンジンに用いられる円環状の熱交換器であって、同軸に配置されたアウターケーシングおよびインナーケーシング間に多数の伝熱板を所定間隔を存して放射状に配置することにより、圧縮空気が通過する高圧通路と燃焼ガスが通過する低圧通路とを円周方向に交互に配置している。燃焼ガスが前方から後方に通過する低圧通路は軸方向に直線状に延びているのに対し、圧縮空気が通過する高圧通路は半径方向外周後部に圧縮空気入口を備えるとともに半径方向内周前部に圧縮空気出口を備えている。従って、圧縮空気は圧縮空気入口から半径方向内向きに流入して軸方向前方に流れた後に圧縮空気出口から半径方向内向きに流出することになり、高圧通路は全体としてクランク状に形成される。
【０００６】
【発明が解決しようとする課題】
ところで、所定間隔をもって積層した多数の伝熱板間に低圧流体通路および高圧流体通路を交互に形成した熱交換器では、高圧流体通路を流れる高圧流体と低圧流体通路を流れる低圧流体との圧力差により伝熱板を低圧流体通路側に押し付ける荷重が発生するため、低圧流体の内部に前記荷重を支持する多数の突起を形成しないと伝熱板間が変形する可能性がある。一方、高圧流体通路の内部には荷重を支持するための突起は特に必要がなく、高圧流体通路の幅を所定の大きさに保持するためのスペーサ的な突起が在れば充分である。
【０００７】
本発明は前述の事情に鑑みてなされたもので、複数の伝熱板を介して低圧流体通路および高圧流体通路を交互に形成した熱交換器において、低圧流体通路および高圧流体通路の圧力差による伝熱板の変形を簡単な構造で確実に防止することを目的とする。
【０００８】
【課題を解決するための手段】
上記目的を達成するために、請求項１に記載された発明によれば、板体を所定間隔で連続的に折り曲げて該折曲部を密着させることにより、一側面に複数の平行な第１凸条を形成した第１伝熱板と、板体の一側面に第１凸条よりも数が少ない複数の第２凸条を形成した第２伝熱板とを交互に重ね合わせた熱交換器であって、第１伝熱板の一側面と第２伝熱板の他側面との間に複数の第１凸条により仕切られた低圧流体通路が形成され、かつ第２伝熱板の一側面と第１伝熱板の他側面との間に複数の第２凸条により仕切られた高圧流体通路が形成され、第２伝熱板の両側縁には、該第２伝熱板の一側面側に折り曲げて形成され第１伝熱板の他側面に先部が直接当接する凸部と、この凸部の前記先部より他側面側に折り曲げて形成される接合部とが設けられ、この接合部と、第１伝熱板の両側縁を一側面側に折り曲げて形成した接合部とが互いに重ね合わされて接合されることを特徴とする熱交換器が提案される。
【０００９】
上記構成によれば、板体を所定間隔で連続的に折り曲げて該折曲部を密着させることにより第１伝熱板の一側面に複数の平行な第１凸条を形成するので、第１伝熱板の一側面と第２伝熱板の他側面とを接合して低圧流体通路を構成したとき、その低圧流体通路の両側に位置する高圧流体通路からの圧力が第１伝熱板および第２伝熱板に作用しても、複数の第１凸条で前記圧力を支持して第１、第２伝熱板の変形を防止することができる。しかも第１凸条は第１伝熱板を折り曲げて形成されるので低コストであるばかりか、第１伝熱板の板厚の２倍の厚さを有するために高い強度を有している。一方、高圧流体通路内に位置する第２伝熱板の第２凸条は前記圧力を支持する必要がないため、その数が第１凸条の数より少なくても何ら支障はなく、従って第２伝熱板の加工コストの削減および重量の軽減に寄与することができる。
【００１０】
また、第２伝熱板の両側縁には、該第２伝熱板の一側面側に折り曲げて形成され第１伝熱板の他側面に先部が直接当接する凸部と、この凸部の前記先部より他側面側に折り曲げて形成される接合部とが設けられ、この接合部に、第１伝熱板の両側縁を一側面側に折り曲げて形成した接合部を重ね合わせて接合するので、第１、第２伝熱板間に区画される高圧流体通路の両側縁を確実にシールして高圧流体の吹き抜けを防止することができると共に、第２伝熱板の一側面の内側縁および外側縁に突設した凸部の先部を第１伝熱板の他側面に当接させることができるので、特別のスペーサ等を必要とせずに第１、第２伝熱板の内側縁および外側縁における相互間隔を設定値に一致させることができる。
【００１１】
また請求項２に記載された発明によれば、請求項１の構成に加えて、第１伝熱板および第２伝熱板を円環状に積層し、第１、第２伝熱板の軸方向前端の半径方向外側縁および半径方向内側縁にそれぞれフロントアウターリングおよびフロントインナーリングを固定するとともに、第１、第２伝熱板の軸方向後端の半径方向外側縁および半径方向内側縁にそれぞれリヤアウターリングおよびリヤインナーリングを固定した後に、第１、第２伝熱板の半径方向外側縁および半径方向内側縁にそれぞれアウターケーシングおよびインナーケーシングを接合してシールすることを特徴とする熱交換器が提案される。
【００１２】
上記構成によれば、円環状に積層した第１、第２伝熱板を４個のリングで固定して位置決めした状態で、その半径方向外側縁および半径方向内側縁にそれぞれアウターケーシングおよびインナーケーシングを接合してシールするので、多数の第１、第２伝熱板を有する熱交換器の組み立てを容易かつ精密に行うことが可能になるだけでなく、高圧流体通路から低圧流体通路への高圧流体の吹き抜けをアウターケーシングおよびインナーケーシングにより一層確実に防止することができる。
【００１３】
また請求項３に記載された発明によれば、請求項２の構成に加えて、第１伝熱板および第２伝熱板をインボリュート曲線状に湾曲させたことを特徴とする熱交換器が提案される。
【００１４】
上記構成によれば、第１伝熱板および第２伝熱板をインボリュート曲線状に湾曲させたので、熱交換器の半径方向の各位置において第１、第２伝熱板の間隔を均一化することができる。
【００１５】
また請求項４に記載された発明によれば、請求項３の構成に加えて、第１、第２伝熱板の半径方向内側縁の接合部をインナーケーシングの外周面に沿わせるとともに、第１、第２伝熱板の半径方向外側縁の接合部をアウターケーシングの内周面に沿わせたことを特徴とする熱交換器が提案される。
【００１６】
上記構成によれば、第１、第２伝熱板の側縁の接合部をインナーケーシングの外周面およびアウターケーシングの内周面に沿わせたので、第１、第２伝熱板の接合部と両ケーシングとを高精度で隙間なく接合して高圧流体の吹き抜けを効果的に防止することができる。
【００１７】
また請求項５に記載された発明によれば、請求項４の構成に加えて、第１、第２伝熱板の半径方向内側縁をインナーケーシングの外周面に直交させたことを特徴とする熱交換器が提案される。
【００１８】
上記構成によれば、第１、第２伝熱板の半径方向内側縁をインナーケーシングの外周面に直交させたので、第１、第２伝熱板を精度良く積層することが可能になるだけでなく、インナーケーシングへの接合精度も高められる。
【００１９】
また請求項６に記載された発明によれば、請求項１の構成に加えて、平板状に形成した第１伝熱板および第２伝熱板を直方体状に積層したことを特徴とする熱交換器が提案される。
【００２０】
上記構成によれば、熱交換器を直方体状に構成してコンパクト化することができる。
【００２１】
【発明の実施の形態】
以下、本発明の実施の形態を、添付図面に示した本発明の実施例に基づいて説明する。
【００２２】
図１〜図７は本発明の第１実施例を示すもので、図１はガスタービンエンジンの縦断面図、図２は図１の２−２線断面図、図３は図２の３−３線拡大断面図、図４は図２の４−４線拡大断面図、図５は図２の５部拡大図、図６は図２の６部拡大図、図７は図４の７−７線断面図である。
【００２３】
先ず、図１に基づいて本実施例の伝熱型熱交換器ＨＥが装着されたガスタービンエンジンＥの構造の概略を説明する。
【００２４】
ガスタービンエンジンＥは概略円筒状に形成されたエンジンケーシング１１を備える。エンジンケーシング１１の外周には第１圧縮空気通路１２が形成されており、この第１圧縮空気通路１２の上流側には図示せぬエアクリーナおよびサイレンサに連なる吸気通路１３が接続される。
【００２５】
吸気通路１３の中央を貫通して一対のベアリング１４，１４で支持された回転軸１５には、遠心式のコンプレッサホイール１６と遠心式のタービンホイール１７とが隣接して同軸に固定される。コンプレッサホイール１６の外周に放射状に形成された複数のコンプレッサブレード１６ａ…は前記吸気通路１３に臨んでおり、これらコンプレッサブレード１６ａ…の直下流に位置する第１圧縮空気通路１２に複数のコンプレッサディフューザ１８…が設けられる。
【００２６】
エンジンケーシング１１の後端には円環状の伝熱型熱交換器ＨＥが配置される。熱交換器ＨＥは後端外周部に圧縮空気入口１９を備えるとともに前端内周部に圧縮空気出口２０を備え、かつ前端に燃焼ガス入口２１を備えるとともに後端に燃焼ガス出口２２を備える。熱交換器ＨＥの内部において、実線で示す比較的に低温高圧の圧縮空気と、破線で示す比較的に高温低圧の燃焼ガスとを相互に逆方向に流すことにより、その流路の全長に亘って圧縮空気および燃焼ガス間の温度差を大きく保ち、熱交換効率を向上させることができる。
【００２７】
熱交換器ＨＥの半径方向内側には円環状のプリヒータ２３が同軸に配置され、更にその半径方向内側には触媒式の単缶型燃焼器２４が同軸に配置される。単缶型燃焼器２４は上流側から下流側に向けて予混合部２５と触媒燃焼部２６と気相燃焼部２７とを順次備えている。熱交換器ＨＥの圧縮空気出口２０とプリヒータ２３とは第２圧縮空気通路２８で接続され、プリヒータ２３と予混合部２５とは第３圧縮空気通路２９で接続される。第３圧縮空気通路２９には燃料噴射ノズル３０が設けられる。燃料噴射ノズル３０から噴射された燃料は、予混合部２５において圧縮空気と均一に混合して有害排出物の少ない燃焼が行われる。このように単缶型燃焼器２４を採用したことにより、アニュラ型燃焼器では困難な触媒燃焼が可能になるばかりか、燃料噴射ノズル３０等の個数を削減して構造の簡略化を図ることができる。
【００２８】
気相燃焼部２７と熱交換器ＨＥの燃焼ガス入口２１とを接続する燃焼ガス通路３１の上流部分には、タービンホイール１７の外周に放射状に形成された複数のタービンブレード１７ａ…が臨むとともに、その更に上流には気相燃焼部２７からの燃焼ガスを導く遮熱板３２およびタービンノズル３３…が設けられる。また燃焼ガス通路３１の下流部分には、燃焼ガス中の有害成分を除去するための円環状の酸化触媒３４が配置される。
【００２９】
しかして、吸気通路１３から吸い込まれてコンプレッサホイール１６により圧縮された空気は第１圧縮空気通路１２を経て熱交換器ＨＥに送られ、そこで高温の燃焼ガスとの間で熱交換することにより加熱される。熱交換器ＨＥを通過した圧縮空気は第２圧縮空気通路２８および第３圧縮空気通路２９を経て予混合部２５に達し、そこで燃料噴射ノズル３０から噴射された燃料と混合する。尚、ガスタービンエンジンＥの始動時には、燃焼ガスが流れないために熱交換器ＨＥが充分に機能しない。従って、始動時には第２、第３圧縮空気通路２８，２９間に設けたプリヒータ２３に通電して圧縮空気を電気的に加熱し、その温度を触媒活性化温度以上に上昇させる必要がある。
【００３０】
単缶型燃焼器２４に流入した混合気の一部は触媒燃焼部２６に担持した触媒に接触して触媒反応により燃焼し、その燃焼ガスの熱によって混合気の残部が気相燃焼部２７において気相燃焼する。燃焼ガスは燃焼ガス通路３１に流入してタービンホイール１７を駆動し、更に酸化触媒３４を通過して有害成分を除去された状態で熱交換器ＨＥに供給される。このようにしてタービンホイール１７が回転すると、その回転トルクは回転軸１５を介してコンプレッサホイール１６および図示せぬ被駆動部に伝達される。
【００３１】
次に、図２〜図７を参照して熱交換器ＨＥの構造を説明する。
【００３２】
円環状の熱交換器ＨＥは矩形状の金属板よりなる多数の第１伝熱板４１と、同一の外形を有する多数の金属板よりなる第２伝熱板４２とを交互に重ね合わせ、その外周面を筒状のアウターケーシング４３で覆い、その内周面を筒状のインナーケーシング４４で覆って構成される。
【００３３】
図３、図５および図６に示すように、第１伝熱板４１は平坦な金属板を長辺と平行に波板状に折り曲げ、それら折り曲げ部分を相互に密着させて一側面側に突出する多数の第１凸条４５…を小間隔で平行に形成してなる。円環状の熱交換器ＨＥの内周部に対応する第１伝熱板４１の内側縁と、外周部に対応する外側縁とには、前記一側面側に折り曲げられた接合部４６，４７がそれぞれ形成される。一方、第２伝熱板４２に接合される第１伝熱板４１の他側面は平坦に形成される。
【００３４】
図４、図５および図６に示すように、第２伝熱板４２は平坦な金属板の一側面に、第１伝熱板４１の第１凸条４５…よりも粗いピッチを有する複数の第２凸条４８…を突設してなる。第２凸条４８…は、第２伝熱板４２の長辺と平行に延びる複数本（実施例では１１本）の主凸条４９…と、円環状の熱交換器ＨＥの圧縮空気入口１９に臨む位置から第２伝熱板４２の短辺と平行に延びる複数本（実施例では３本）の入口凸条５０ａ，５０ｂ，５０ｃと、円環状の熱交換器ＨＥの圧縮空気出口２０に臨む位置から第２伝熱板４２の短辺と平行に延びる複数本（実施例では３本）の出口凸条５１ａ，５１ｂ，５１ｃとを備える。一方、第１伝熱板４１に接合される第２伝熱板４２の他側面は平坦に形成される。
【００３５】
尚、３本の入口凸条５０ａ，５０ｂ，５０ｃのうち、第２伝熱板４２の後端側の１本の入口凸条５０ａは、シール性を高めるべく他の２本の入口凸条５０ｂ，５０ｃよりも幅広に形成されている。これは、他の２本の入口凸条５０ｂ，５０ｃが隣接する通路を仕切る役目を果たすのに対し、１本の入口凸条５０ａは熱交換器ＨＥの後端を土手状に仕切って閉塞する閉塞部材を兼ねるためである。同様に、３本の出口凸条５１ａ，５１ｂ，５１ｃのうち、第２伝熱板４２の前端側の１本の出口凸条５１ａは他の２本の出口凸条５１ｂ，５１ｃよりも幅広に形成されており、熱交換器ＨＥの前端を土手状に仕切って閉塞する閉塞部材を兼ねている。
【００３６】
３本の入口凸条５０ａ，５０ｂ，５０ｃの長さは、第２伝熱板４２の後端側の入口凸条５０ａが最も長く形成されて該第２伝熱板４２の短辺と同じ長さであり、第２伝熱板４２の後端側から遠いものほど短くなっている。主凸条４９…の長さは一定ではなく、第２伝熱板４２の後端側から２番目に遠い入口凸条５０ｂの端部と３番目に遠い入口凸条５０ｃの端部との間に間隙α，βを有している。また３本の出口凸条５１ａ，５１ｂ，５１ｃの長さは、第２伝熱板４２の前端側の出口凸条５１ａが最も長く形成されて該第２伝熱板４２の短辺と同じ長さであり、第２伝熱板４２の前端側から遠いものほど短くなっている。第２伝熱板４２の前端側から２番目に遠い出口凸条５１ｂの端部と３番目に遠い出口凸条５１ｃの端部とは、２本の主凸条４９，４９の端部に滑らかな円弧で連なっている。
【００３７】
円環状の熱交換器ＨＥの内周部および外周部にそれぞれ対応する第２伝熱板４２の内側縁および外側縁には、前記一側面側に折り曲げられた凸部５４，５５と、これら凸部５４，５５の先部に連なって前記他側面側に折り曲げられた接合部５６，５７がそれぞれ形成される。凸部５４，５５の高さは第２凸条４８…の高さに等しく設定され、前記先部は第１伝熱板４１の他側面に直接当接する。第２伝熱板４２の接合部５６，５７は、第１伝熱板４１の接合部４６，４７の内面に一部がオーバーラップするように重ね合わされる。
【００３８】
仮に第１伝熱板４１および第２伝熱板４２を放射状に配置すると、円環状の熱交換器ＨＥの内周部では隣接する第１、第２伝熱板４１，４２の間隔が狭くなり、外周部では前記間隔が広くなってしまうが、図５および図６から明らかなように、第１伝熱板４１および第２伝熱板４２をインボリュート曲線状に湾曲させることにより、熱交換器ＨＥの内周部および外周部で隣接する第１、第２伝熱板４１，４２の間隔を均一にすることができる。ただし、第１伝熱板４１および第２伝熱板４２をインボリュート曲線状に湾曲させたことにより、熱交換器ＨＥの内周部では第１、第２伝熱板４１および４２がインナーケーシング４４に対して略直角に交差するが、アウターケーシング４３に対して鋭角に交差することになる。
【００３９】
図３および図４から明らかなように、交互に重ね合わされて円環状に組み合わされた第１伝熱板４１および第２伝熱板４２は、その前部外周および後部外周にそれぞれフロントアウターリング５８およびリヤアウターリング５９が嵌合するとともに、その前部内周および後部内周にそれぞれフロントインナーリング６０およびリヤインナーリング６１が嵌合して位置決めされる。そして円環状に組み合わされた第１伝熱板４１および第２伝熱板４２の外周面を覆ってシールするアウターケーシング４３は、その前端の拡径部４３ａがフロントアウターリング５８の外周面に嵌合し、その後端とリヤアウターリング５９との間に圧縮空気入口１９が開口する。また第１伝熱板４１および第２伝熱板４２の内周面を覆ってシールするインナーケーシング４４は、その後端の拡径部４４ａがリヤインナーリング６１の内周面に嵌合し、その前端とフロントインナーリング６０との間に圧縮空気出口２０が開口する。
【００４０】
このように、第１伝熱板４１および第２伝熱板４２をフロントアウターリング５８、リヤアウターリング５９、フロントインナーリング６０およびリヤインナーリング６１で一体化した後に、その外周面および内周面にアウターケーシング４３およびインナーケーシング４４を接合するので、多数の第１伝熱板４１および第２伝熱板４２を有する熱交換器ＨＥの組立が容易になるだけでなく、組立精度を高めることができる。しかもアウターケーシング４３およびインナーケーシング４４の接合により、第１伝熱板４１および第２伝熱板４２の外周面および内周面における圧縮空気の吹き抜けを一層効果的に防止することができる。
【００４１】
前記第１伝熱板４１、第２伝熱板４２、フロントアウターリング５８、リヤアウターリング５９、フロントインナーリング６０、リヤインナーリング６１、アウターケーシング４３およびインナーケーシング４４はろう付けにより接合される。図５から明らかなように、第１伝熱板４１および第２伝熱板４２がインナーケーシング４４にろう付けされる部分において、第１伝熱板４１の幅狭の接合部４６は第２伝熱板４２の幅広の接合部５６の外面の一部にオーバーラップするように重ね合わされており、第２伝熱板４２の接合部５６の大部分は第１伝熱板４１の板厚の相当する隙間を介してインナーケーシング４４の外周面に対向する。従って、前記隙間に黒塗りで示すろう材を流して確実にろう付けし、熱交換器ＨＥの組立強度を確保するとともに圧縮空気および燃焼ガスの吹き抜けを防止することができる。
【００４２】
同様に、図６から明らかなように、第１伝熱板４１および第２伝熱板４２がアウターケーシング４３にろう付けされる部分において、第１伝熱板４１の幅狭の接合部４７は第２伝熱板４２の幅広の接合部５７の外面の一部にオーバーラップするように重ね合わされており、第２伝熱板４２の接合部５７の大部分は第１伝熱板４１の板厚の相当する隙間を介してアウターケーシング４３の内周面に対向する。従って、前記隙間に黒塗りで示すろう材を流して確実にろう付けし、熱交換器ＨＥの組立強度を確保するとともに圧縮空気および燃焼ガスの吹き抜けを防止することができる。
【００４３】
特に、インボリュート曲線状に湾曲する第１伝熱板４１および第２伝熱板４２の内側縁はインナーケーシング４４の外周面に略直角に交差するので、第１伝熱板４１および第２伝熱板４２を精度良く積層することが可能となり、ろう付け精度を高めて後述する高圧流体通路６３…側から低圧流体通路６２…側への圧縮空気の吹き抜けを効果的に防止することができる。
【００４４】
図３から明らかなように、第１凸条４５…が突出する第１伝熱板４１の一側面と平坦な第２伝熱板４２の他側面との間には、燃焼ガス入口２１および燃焼ガス出口２２を接続すべく、第１凸条４５…により仕切られた直線状かつ平行な複数の低圧流体通路６２…が区画される。
【００４５】
図４から明らかなように、第２凸条４８…が突出する第２伝熱板４２の一側面と平坦な第１伝熱板４１の他側面との間には、圧縮空気入口１９および圧縮空気出口２０を接続すべく高圧流体通路６３…が形成される。高圧流体通路６３…は、第２凸条４８…により仕切られた入口流体通路６５ａ，６５ｂ、主流体通路６４…および出口流体通路６６ａ，６６ｂを有してクランク状に形成される。即ち、入口凸条５０ａ，５０ｂ，５０ｃ間に圧縮空気入口１９から半径方向内側に向かって延びる入口流体通路６５ａ，６５ｂが形成され、主凸条４９…間に軸方向に延びる主流体通路６４…が形成され、出口凸条５１ａ，５１ｂ，５１ｃ間に圧縮空気出口２０から半径方向外側に向かって延びる出口流体通路６６ａ，６６ｂが形成される。
【００４６】
低圧流体通路６２…との間で熱交換する高圧流体通路６３…の主流体通路６４…は、図４に鎖線で示すように略平行四辺形に形成されているので、入口流体通路６５ａ，６５ｂおよび出口流体通路６６ａ，６６ｂのスペースを確保しながら、熱交換のための伝熱面積（主流体通路６４…の面積）を最大限に増加させて熱交換効率を高めることができる。
【００４７】
しかして、単缶型燃焼器２４において発生してタービンホイール１７を駆動した比較的に高温低圧の燃焼ガスは、燃焼ガス通路３１を経て熱交換器ＨＥの前端の燃焼ガス入口２１から低圧流体通路６２…を通過し、熱交換器ＨＥの後端の燃焼ガス出口２２から排出される。一方、コンプレッサホイール１６で圧縮された比較的に低温高圧の圧縮空気は、ガスタービンエンジンＥの外周に形成された第１圧縮空気通路１２を後方に流れた後に、熱交換器ＨＥの後端外周部に形成された圧縮空気入口１９から半径方向内向きに９０°方向を変えて入口流体通路６５ａ，６５ｂに流入し、そこから９０°方向を変えて主流体通路６４…を前方に流れる。そして主流体通路６４…の前端において圧縮空気は更に半径方向内向きに９０°向きを変えて熱交換器ＨＥの前端内周部に形成された圧縮空気出口２０から第２圧縮空気通路２８に排出される。
【００４８】
このように、熱交換器ＨＥは第１伝熱板４１および第２伝熱板４２間に交互に形成された低圧流体通路６２…および高圧流体通路６３…を備え、高温の燃焼ガスは低圧流体通路６２…を前方から後方に流れ、低温の圧縮空気は高圧流体通路を後方から前方に流れるので、いわゆるクロスフロー状態を実現して熱交換器ＨＥの軸方向の全長に亘って燃焼ガスおよび圧縮空気間の温度差を大きく保ち、熱交換効率を向上させることができる。
【００４９】
ところで、第１圧縮空気通路１２を後方に流れた圧縮空気は熱交換器ＨＥの入口流体通路６５ａ，６５ｂにおいて１８０°旋回（図１の矢印Ａ参照）した後に熱交換器ＨＥの主流体通路６４…を前方に流れるが、その旋回の際に作用する遠心力で圧縮空気は旋回方向外側に付勢されるため、軸方向に沿って平行に形成された多数の主流体通路６４…のうち、旋回方向外側の主流体通路６４…、つまり熱交換器ＨＥの半径方向内側の主流体通路６４…に供給される圧縮空気量が増加し、逆に熱交換器ＨＥの半径方向外側の主流体通路６４…に供給される圧縮空気量が減少する傾向が発生してしまう。
【００５０】
しかしながら、本実施例によれば、３本の入口凸条５０ａ，５０ｂ，５０ｃにより区画される入口流体通路６５ａ，６５ｂのうち、旋回方向外側の入口流体通路６５ａの幅Ｗａを狭くするとともに旋回方向内側の入口流体通路６５ｂの幅Ｗｂを広くし、かつ第２伝熱板４２の後端側から２番目に遠い入口凸条５０ｂの端部と３番目に遠い入口凸条５０ｃの端部とが、主凸条４９…の端部との間に間隙α，βを有しており、更に主凸条４９…の長さが不均一で該主凸条４９…の前後端の位置が前後方向に調整されていることにより、半径方向の位置に関わらず全ての主流体通路６４…に流入する圧縮空気量を均一化することができる。
【００５１】
なぜならば、遠心力で圧縮空気の流量が増加する傾向にある旋回方向外側の入口流体通路６５ａの幅Ｗａを狭くし、逆に圧縮空気の流量が減少する傾向にある旋回方向内側の入口流体通路６５ｂの幅Ｗｂを広くすることにより、入口流体通路６５ａ，６５ｂから主流体通路６４…への圧縮空気配分量を均一化することができる。しかも２本の入口凸条５０ｂ，５０ｃの下流端が主凸条４９，４９の上流端に接続せずに間隙α，βが形成されており、かつ主凸条４９…の前後端の位置が前後方向に調整されているので、主流体通路６４…の圧縮空気配分量を更に効果的に均一化することができる。
【００５２】
一方、２本の主凸条４９，４９が２本の出口凸条５１ｂ，５１ｃに滑らかに連なっており、しかも２本の出口流体通路６６ａ，６６ｂの幅Ｗｃ，Ｗｄが同一でないように設定されているので、主流体通路６４…を流れる圧縮空気を出口流体通路６６ａ，６６ｂにスムーズに案内して圧損の発生を最小限に抑えることができる。
【００５３】
主流体通路６４…、入口流体通路６５ａ，６５ｂおよび出口流体通路６６ａ，６６ｂを上述のように構成したことにより、全体としてクランク状の屈曲した高圧流体通路６３の全域に亘って圧縮空気を均一にかつスムーズに流すことが可能となる。
【００５４】
また高圧流体通路６３…を流れる圧縮空気の圧力は低圧流体通路６２…を流れる燃焼ガスの圧力よりも高いため、隣接する高圧流体通路６３，６３に挟まれた低圧流体通路６２を区画する第１伝熱板４１および第２伝熱板４２が、圧縮空気および燃焼ガスの圧力差で相互に接近する方向の荷重を受けることになる。しかしながら、第１伝熱板４１の一側面に小さいピッチで突設した多数の第１凸条４５…で第２伝熱板４２の他側面を支持することにより、圧縮空気および燃焼ガスの圧力差で第１伝熱板４１および第２伝熱板４２が変形するのを確実に防止することができる。しかも第１凸条４５…は第１伝熱板４１を所定間隔で連続的に折り曲げて折曲部を相互に密着させて形成されるので、その部分の板厚が２倍になって前記圧力差を支持する剛性が高められるだけでなく、加工コストを大幅に削減することができる。
【００５５】
尚、隣接する低圧流体通路６２，６２に挟まれた高圧流体通路６３を区画する第１伝熱板４１および第２伝熱板４２は、圧縮空気および燃焼ガスの圧力差で相互に離反する方向の荷重を受けるため、その高圧流体通路６３の内部に配置された第２伝熱板４２の第２凸条４８…のピッチを粗く設定しても、強度上の問題は何ら発生しない。従って、第２凸条４８…は第１伝熱板４１および第２伝熱板４２の間隔を保持し得るピッチで形成すれば充分であり、第２伝熱板４２の加工コストおよび重量軽減に寄与することができる。
【００５６】
更に、第２伝熱板４１の一側面の内側縁および外側縁に突設した凸部５４，５５の先部を第１伝熱板４２の他側面に直接当接させたので、特別のスペーサ等を必要とせずに第１、第２伝熱板４１，４２の内側縁および外側縁における相互間隔を設定値に一致させることができる。
【００５７】
図８および図９は本発明の第２実施例を示すもので、図８は熱交換器の斜視図、図９は図８の９方向矢視図である。
【００５８】
上述した第１実施例の熱交換器ＨＥは円環状に形成されているのに対し、第２実施例の熱交換器ＨＥは直方体状に形成されている。第１伝熱板４１および第２伝熱板４２の構造は第１実施例のものと実質的に同一であるが、第１実施例の第１、第２伝熱板４１，４２がインボリュート曲線状に湾曲しているのに対し、第２実施例の第１、第２伝熱板４１，４２は平面状に形成される。
【００５９】
交互に積層された第１、第２伝熱板４１，４２の一方の側縁は前記アウターケーシング４３に対応する端板４３′に接合され、他方の側縁は前記インナーケーシング４４に対応する端板４４′に接合される。また第１、第２伝熱板４１，４２の積層方向の両面には、一対の側板７１，７２が接合される。第１、第２伝熱板４１，４２の側縁と両端板４３′，４４′とは直角に交差するため、第１実施例における第１、第２伝熱板４１，４２の側縁とインナーケーシング４３との接合部と同じ構造で接合される（図９参照）。高温の燃焼ガスは熱交換器ＨＥの前端の燃焼ガス入口２１から流入して後端の燃焼ガス出口２２から流出し、低温の圧縮空気は一方の端板４３′の後端に形成した圧縮空気入口１９から流入して他方の端板４４′の前端に形成した圧縮空気出口２０から流出する。
【００６０】
しかして、本第２実施例によっても、前記第１実施例と同じ作用効果を奏することができ、しかも熱交換器ＨＥがコンパクトになる。
【００６１】
以上、本発明の実施例を詳述したが、本発明はその要旨を逸脱しない範囲で種々の設計変更を行うことが可能である。
【００６２】
【発明の効果】
以上のように、請求項１に記載された発明によれば、板体を所定間隔で連続的に折り曲げて該折曲部を密着させることにより第１伝熱板の一側面に複数の平行な第１凸条を形成するので、第１伝熱板の一側面と第２伝熱板の他側面とを接合して低圧流体通路を構成したとき、その低圧流体通路の両側に位置する高圧流体通路からの圧力が第１伝熱板および第２伝熱板に作用しても、複数の第１凸条で前記圧力を支持して第１、第２伝熱板の変形を防止することができる。しかも第１凸条は第１伝熱板を折り曲げて形成されるので低コストであるばかりか、第１伝熱板の板厚の２倍の厚さを有するために高い強度を有している。一方、高圧流体通路内に位置する第２伝熱板の第２凸条は前記圧力を支持する必要がないため、その数が第１凸条の数より少なくても何ら支障はなく、従って第２伝熱板の加工コストの削減および重量の軽減に寄与することができる。
【００６３】
また、第２伝熱板の両側縁には、該第２伝熱板の一側面側に折り曲げて形成され第１伝熱板の他側面に先部が直接当接する凸部と、この凸部の前記先部より他側面側に折り曲げて形成される接合部とが設けられ、この接合部に、第１伝熱板の両側縁を一側面側に折り曲げて形成した接合部を重ね合わせて接合するので、第１、第２伝熱板間に区画される高圧流体通路の両側縁を確実にシールして高圧流体の吹き抜けを防止することができると共に、第２伝熱板の一側面の内側縁および外側縁に突設した凸部の先部を第１伝熱板の他側面に当接させることができるので、特別のスペーサ等を必要とせずに第１、第２伝熱板の内側縁および外側縁における相互間隔を設定値に一致させることができる。
【００６４】
また請求項２に記載された発明によれば、円環状に積層した第１、第２伝熱板を４個のリングで固定して位置決めした状態で、その半径方向外側縁および半径方向内側縁にそれぞれアウターケーシングおよびインナーケーシングを接合してシールするので、多数の第１、第２伝熱板を有する熱交換器の組み立てを容易かつ精密に行うことが可能になるだけでなく、高圧流体通路から低圧流体通路への高圧流体の吹き抜けをアウターケーシングおよびインナーケーシングにより一層確実に防止することができる。
【００６５】
また請求項３に記載された発明によれば、第１伝熱板および第２伝熱板をインボリュート曲線状に湾曲させたので、熱交換器の半径方向の各位置において第１、第２伝熱板の間隔を均一化することができる。
【００６６】
また請求項４に記載された発明によれば、第１、第２伝熱板の側縁の接合部をインナーケーシングの外周面およびアウターケーシングの内周面に沿わせたので、第１、第２伝熱板の接合部と両ケーシングとを高精度で隙間なく接合して高圧流体の吹き抜けを効果的に防止することができる。
【００６７】
また請求項５に記載された発明によれば、第１、第２伝熱板の半径方向内側縁をインナーケーシングの外周面に直交させたので、第１、第２伝熱板を精度良く積層することが可能になるだけでなく、インナーケーシングへの接合精度も高められる。
【００６８】
また請求項６に記載された発明によれば、熱交換器を直方体状に構成してコンパクト化することができる。
【図面の簡単な説明】
【図１】ガスタービンエンジンの縦断面図
【図２】図１の２−２線拡大断面図
【図３】図２の３−３線拡大断面図
【図４】図２の４−４線拡大断面図
【図５】図２の５部拡大図
【図６】図２の６部拡大図
【図７】図４の７−７線断面図
【図８】第２実施例に係る熱交換器の斜視図
【図９】図８の９方向矢視図
【符号の説明】
４１第１伝熱板
４２第２伝熱板
４５第１凸条
４６，４７接合部
４８第２凸条
５６，５７接合部
５８フロントアウターリング
５９リヤアウターリング
６０フロントインナーリング
６１リヤインナーリング
６２低圧流体通路
６３高圧流体通路[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a heat exchanger in which first heat transfer plates and second heat transfer plates are alternately overlapped, and low-pressure fluid passages and high-pressure fluid passages are alternately formed between the two heat transfer plates.
[0002]
[Prior art]
  A heat exchanger for exchanging heat between a high-temperature fluid and a low-temperature fluid by alternately arranging fluid passages through which a high-temperature fluid flows and fluid passages through which a low-temperature fluid flows is disclosed in, for example, Japanese Utility Model Laid-Open No. 3-79082 and Japanese Patent Laid-Open No. 5- No. 506918 and US Pat. No. 3,831,374 are already known.
[0003]
  In Japanese Utility Model Laid-Open No. 3-79082, a plurality of interval holding portions extending in parallel to each other are formed by bending a paper partition plate at a predetermined interval, and the interval holding portions are orthogonal to each other. In this way, fluid passages through which the high-temperature fluid flows and fluid passages through which the low-temperature fluid flows are alternately formed between adjacent partition plates.
[0004]
  Moreover, what is described in the above Japanese translation of PCT publication No. 5-506918 is an annular heat exchanger used in a gas turbine engine, and is curved in an involute curve between an outer casing and an inner casing arranged coaxially. By arranging a large number of the heat transfer plates at predetermined intervals, the high-pressure passages through which the compressed air passes and the low-pressure passages through which the combustion gas passes are alternately arranged in the circumferential direction.
[0005]
  In addition, what is described in the above-mentioned U.S. Pat. No. 3,831,374 is an annular heat exchanger used in a gas turbine engine, in which a large number of heat transfer plates are provided between an outer casing and an inner casing arranged coaxially. By arranging them radially at predetermined intervals, high-pressure passages through which compressed air passes and low-pressure passages through which combustion gas passes are alternately arranged in the circumferential direction. The low-pressure passage through which the combustion gas passes from the front to the rear extends linearly in the axial direction, whereas the high-pressure passage through which the compressed air passes has a compressed air inlet at the rear end in the radial direction and the front portion in the radial direction. Has a compressed air outlet. Accordingly, the compressed air flows inward in the radial direction from the compressed air inlet, flows axially forward, and then flows out inward in the radial direction from the compressed air outlet, and the high-pressure passage is formed in a crank shape as a whole. .
[0006]
[Problems to be solved by the invention]
  By the way, in a heat exchanger in which low-pressure fluid passages and high-pressure fluid passages are alternately formed between a large number of heat transfer plates stacked at a predetermined interval, the pressure difference between the high-pressure fluid flowing in the high-pressure fluid passage and the low-pressure fluid flowing in the low-pressure fluid passage. As a result, a load that presses the heat transfer plate toward the low-pressure fluid passage is generated. Therefore, the heat transfer plates may be deformed unless a large number of protrusions supporting the load are formed in the low-pressure fluid. On the other hand, there is no particular need for a protrusion for supporting a load inside the high-pressure fluid passage, and it is sufficient if there is a spacer-like protrusion for maintaining the width of the high-pressure fluid passage at a predetermined size.
[0007]
  The present invention has been made in view of the above circumstances, and in a heat exchanger in which a low pressure fluid passage and a high pressure fluid passage are alternately formed via a plurality of heat transfer plates, the pressure difference between the low pressure fluid passage and the high pressure fluid passage is determined. The object is to reliably prevent deformation of the heat transfer plate with a simple structure.
[0008]
[Means for Solving the Problems]
  In order to achieve the above object, according to the first aspect of the present invention, a plurality of parallel first lines are formed on one side surface by continuously bending a plate body at a predetermined interval and closely contacting the bent portion. Heat exchange in which the first heat transfer plate formed with ridges and the second heat transfer plate formed with a plurality of second ridges having a smaller number than the first ridges on one side of the plate are alternately stacked. A low-pressure fluid passage partitioned by a plurality of first ridges is formed between one side surface of the first heat transfer plate and the other side surface of the second heat transfer plate, and the second heat transfer plate A high-pressure fluid passage partitioned by a plurality of second ridges is formed between one side and the other side of the first heat transfer plate.A convex portion formed on the both side edges of the second heat transfer plate by bending to one side surface of the second heat transfer plate and having a tip directly contacting the other side surface of the first heat transfer plate; A joining portion formed by bending the tip portion to the other side surface is provided, and the joining portion and a joining portion formed by folding both side edges of the first heat transfer plate to one side surface are overlapped with each other. JoinedA heat exchanger characterized by the above is proposed.
[0009]
  According to the above configuration, since the plate body is continuously bent at a predetermined interval and the bent portions are brought into close contact with each other, a plurality of first parallel ridges are formed on one side surface of the first heat transfer plate. When one side surface of the heat transfer plate and the other side surface of the second heat transfer plate are joined to form the low pressure fluid passage, the pressure from the high pressure fluid passage located on both sides of the low pressure fluid passage is changed to the first heat transfer plate and Even if it acts on the second heat transfer plate, the first and second heat transfer plates can be prevented from being deformed by supporting the pressure with a plurality of first protrusions. Moreover, since the first ridge is formed by bending the first heat transfer plate, it is not only low in cost, but also has a high strength because it has twice the thickness of the first heat transfer plate. . On the other hand, since the second ridges of the second heat transfer plate located in the high-pressure fluid passage do not need to support the pressure, there is no problem even if the number thereof is smaller than the number of the first ridges. 2 It can contribute to the reduction of the processing cost and weight of the heat transfer plate.
[0010]
  AlsoA convex portion formed on the both side edges of the second heat transfer plate by bending to one side surface of the second heat transfer plate and having a tip directly contacting the other side surface of the first heat transfer plate; And a joint formed by bending the other end side than the tip is provided.Joining formed by bending both side edges of the first heat transfer plate to one sidePartSince they are overlapped and joined, both side edges of the high-pressure fluid passage defined between the first and second heat transfer plates can be reliably sealed to prevent the high-pressure fluid from being blown out.At the same time, the tip of the convex portion protruding from the inner edge and the outer edge of one side surface of the second heat transfer plate can be brought into contact with the other side surface of the first heat transfer plate, so that a special spacer or the like is required. The mutual interval between the inner and outer edges of the first and second heat transfer plates can be matched with the set value.
[0011]
  And claims2According to the invention described in claim1In addition to the above structure, the first heat transfer plate and the second heat transfer plate are laminated in an annular shape, and the front outer layer is disposed on the radially outer edge and the radially inner edge of the front end in the axial direction of the first and second heat transfer plates, respectively. After fixing the ring and the front inner ring, after fixing the rear outer ring and the rear inner ring to the radially outer edge and the radially inner edge of the axial rear ends of the first and second heat transfer plates, respectively, A heat exchanger is proposed in which an outer casing and an inner casing are joined and sealed to the radially outer edge and the radially inner edge of the second heat transfer plate, respectively.
[0012]
  According to the above configuration, in the state where the first and second heat transfer plates stacked in an annular shape are fixed and positioned by the four rings, the outer casing and the inner casing are disposed at the radially outer edge and the radially inner edge, respectively. As a result, the heat exchanger having a large number of first and second heat transfer plates can be assembled easily and precisely, and the high pressure from the high pressure fluid passage to the low pressure fluid passage can be increased. Fluid blow-out can be prevented more reliably by the outer casing and the inner casing.
[0013]
  And claims3According to the invention described in claim2In addition to the above configuration, a heat exchanger is proposed in which the first heat transfer plate and the second heat transfer plate are curved in an involute curve.
[0014]
  According to the above configuration, since the first heat transfer plate and the second heat transfer plate are curved in an involute curve, the distance between the first and second heat transfer plates is made uniform at each position in the radial direction of the heat exchanger. can do.
[0015]
  And claims4According to the invention described in claim3In addition to the above configuration, the joint portion of the inner edge in the radial direction of the first and second heat transfer plates is set along the outer peripheral surface of the inner casing, and the joint portion of the outer edge in the radial direction of the first and second heat transfer plates is provided. A heat exchanger characterized by being along the inner peripheral surface of the outer casing is proposed.
[0016]
  According to the above configuration, since the joint portions of the side edges of the first and second heat transfer plates are aligned with the outer peripheral surface of the inner casing and the inner peripheral surface of the outer casing, the joint portions of the first and second heat transfer plates. And the two casings can be joined to each other with high accuracy without any gaps, thereby effectively preventing the high pressure fluid from being blown through.
[0017]
  And claims5According to the invention described in claim4In addition to the above configuration, a heat exchanger is proposed in which the radially inner edges of the first and second heat transfer plates are orthogonal to the outer peripheral surface of the inner casing.
[0018]
  According to the above configuration, since the radially inner edges of the first and second heat transfer plates are orthogonal to the outer peripheral surface of the inner casing, only the first and second heat transfer plates can be accurately stacked. In addition, the accuracy of joining to the inner casing can be improved.
[0019]
  And claims6According to the invention described in claim 1, in addition to the configuration of claim 1, a heat exchanger is proposed in which the first heat transfer plate and the second heat transfer plate formed in a flat plate shape are stacked in a rectangular parallelepiped shape. Is done.
[0020]
  According to the said structure, a heat exchanger can be comprised in a rectangular parallelepiped shape and can be compactized.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described based on examples of the present invention shown in the accompanying drawings.
[0022]
  1 to 7 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a gas turbine engine, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. 4 is an enlarged sectional view taken along line 4-4 of FIG. 2, FIG. 5 is an enlarged view of 5 part of FIG. 2, FIG. 6 is an enlarged view of 6 part of FIG. 2, and FIG. FIG.
[0023]
  First, based on FIG. 1, the outline of the structure of the gas turbine engine E with which the heat-transfer type heat exchanger HE of the present Example was mounted is demonstrated.
[0024]
  The gas turbine engine E includes an engine casing 11 formed in a substantially cylindrical shape. A first compressed air passage 12 is formed on the outer periphery of the engine casing 11, and an intake passage 13 connected to an air cleaner and a silencer (not shown) is connected to the upstream side of the first compressed air passage 12.
[0025]
  A centrifugal compressor wheel 16 and a centrifugal turbine wheel 17 are adjacently and coaxially fixed to a rotating shaft 15 that passes through the center of the intake passage 13 and is supported by a pair of bearings 14 and 14. A plurality of compressor blades 16a formed radially on the outer periphery of the compressor wheel 16 face the intake passage 13, and a plurality of compressor diffusers 18 are disposed in the first compressed air passage 12 located immediately downstream of the compressor blades 16a. ... are provided.
[0026]
  An annular heat transfer type heat exchanger HE is disposed at the rear end of the engine casing 11. The heat exchanger HE includes a compressed air inlet 19 at the rear end outer peripheral portion, a compressed air outlet 20 at the front end inner peripheral portion, a combustion gas inlet 21 at the front end, and a combustion gas outlet 22 at the rear end. In the heat exchanger HE, a relatively low temperature and high pressure compressed air indicated by a solid line and a relatively high temperature and low pressure combustion gas indicated by a broken line are caused to flow in opposite directions, thereby extending the entire length of the flow path. Thus, the temperature difference between the compressed air and the combustion gas can be kept large, and the heat exchange efficiency can be improved.
[0027]
  An annular preheater 23 is coaxially arranged on the inner side in the radial direction of the heat exchanger HE, and a catalytic single can type combustor 24 is coaxially arranged on the inner side in the radial direction. The single can type combustor 24 includes a premixing unit 25, a catalytic combustion unit 26, and a gas phase combustion unit 27 sequentially from the upstream side to the downstream side. The compressed air outlet 20 of the heat exchanger HE and the preheater 23 are connected by a second compressed air passage 28, and the preheater 23 and the premixing unit 25 are connected by a third compressed air passage 29. A fuel injection nozzle 30 is provided in the third compressed air passage 29. The fuel injected from the fuel injection nozzle 30 is uniformly mixed with the compressed air in the premixing unit 25 and burned with less harmful emissions. By adopting the single can type combustor 24 in this way, not only can the catalytic combustion difficult with the annular type combustor be possible, but also the number of fuel injection nozzles 30 and the like can be reduced to simplify the structure. it can.
[0028]
  A plurality of turbine blades 17a formed radially on the outer periphery of the turbine wheel 17 face the upstream portion of the combustion gas passage 31 connecting the gas phase combustion section 27 and the combustion gas inlet 21 of the heat exchanger HE, Further upstream, a heat shield plate 32 and a turbine nozzle 33... For guiding the combustion gas from the gas phase combustion unit 27 are provided. An annular oxidation catalyst 34 for removing harmful components in the combustion gas is disposed in the downstream portion of the combustion gas passage 31.
[0029]
  Thus, the air sucked from the intake passage 13 and compressed by the compressor wheel 16 is sent to the heat exchanger HE through the first compressed air passage 12, where it is heated by exchanging heat with the high-temperature combustion gas. Is done. The compressed air that has passed through the heat exchanger HE reaches the premixing section 25 through the second compressed air passage 28 and the third compressed air passage 29, where it is mixed with the fuel injected from the fuel injection nozzle 30. Note that when the gas turbine engine E is started, the heat exchanger HE does not function sufficiently because combustion gas does not flow. Therefore, at the time of starting, it is necessary to energize the preheater 23 provided between the second and third compressed air passages 28 and 29 to electrically heat the compressed air, and to raise the temperature above the catalyst activation temperature.
[0030]
  A part of the air-fuel mixture flowing into the single can combustor 24 comes into contact with the catalyst carried on the catalytic combustion section 26 and burns by a catalytic reaction, and the remainder of the air-fuel mixture is heated in the gas-phase combustion section 27 by the heat of the combustion gas. Gas phase combustion. The combustion gas flows into the combustion gas passage 31 to drive the turbine wheel 17 and further passes through the oxidation catalyst 34 to be supplied to the heat exchanger HE in a state where harmful components are removed. When the turbine wheel 17 rotates in this way, the rotational torque is transmitted to the compressor wheel 16 and a driven part (not shown) via the rotating shaft 15.
[0031]
  Next, the structure of the heat exchanger HE will be described with reference to FIGS.
[0032]
  The annular heat exchanger HE alternately superimposes a plurality of first heat transfer plates 41 made of rectangular metal plates and a plurality of second heat transfer plates 42 made of many metal plates having the same outer shape, The outer peripheral surface is covered with a cylindrical outer casing 43, and the inner peripheral surface is covered with a cylindrical inner casing 44.
[0033]
  As shown in FIGS. 3, 5, and 6, the first heat transfer plate 41 is formed by bending a flat metal plate into a corrugated plate parallel to the long side, and sticking the bent portions to each other to project to one side. A plurality of first ridges 45 are formed in parallel at small intervals. On the inner edge of the first heat transfer plate 41 corresponding to the inner peripheral portion of the annular heat exchanger HE and the outer edge corresponding to the outer peripheral portion, joint portions 46 and 47 bent to the one side face are provided. Each is formed. On the other hand, the other side surface of the first heat transfer plate 41 joined to the second heat transfer plate 42 is formed flat.
[0034]
  As shown in FIGS. 4, 5 and 6, the second heat transfer plate 42 has a plurality of pitches on one side of a flat metal plate having a coarser pitch than the first protrusions 45 of the first heat transfer plate 41. The second ridges 48 are projected. The second ridges 48 are a plurality of (11 in the embodiment) main ridges 49 extending in parallel with the long side of the second heat transfer plate 42 and the compressed air inlet 19 of the annular heat exchanger HE. To the plurality of (three in the embodiment) inlet ridges 50a, 50b, and 50c extending in parallel with the short side of the second heat transfer plate 42 and the compressed air outlet 20 of the annular heat exchanger HE. A plurality of (three in the embodiment) exit ridges 51a, 51b, 51c extending in parallel with the short side of the second heat transfer plate 42 from the facing position are provided. On the other hand, the other side surface of the second heat transfer plate 42 joined to the first heat transfer plate 41 is formed flat.
[0035]
  Of the three inlet ridges 50a, 50b, 50c, one inlet ridge 50a on the rear end side of the second heat transfer plate 42 is the other two inlet ridges 50b in order to improve the sealing performance. , 50c. This serves to partition the adjacent passages by the other two inlet ridges 50b and 50c, whereas one inlet ridge 50a partitions and closes the rear end of the heat exchanger HE in a bank shape. This is because it also serves as a closing member. Similarly, of the three outlet ridges 51a, 51b, 51c, one outlet ridge 51a on the front end side of the second heat transfer plate 42 is wider than the other two outlet ridges 51b, 51c. It is formed and also serves as a blocking member that partitions and closes the front end of the heat exchanger HE in a bank shape.
[0036]
  The length of the three inlet ridges 50a, 50b, 50c is the same as the short side of the second heat transfer plate 42, with the longest length of the inlet ridge 50a on the rear end side of the second heat transfer plate 42 formed. That is, the farther from the rear end side of the second heat transfer plate 42, the shorter. The length of the main ridges 49 is not constant, and is between the end of the inlet ridge 50b farthest from the rear end side of the second heat transfer plate 42 and the end of the inlet ridge 50c farthest from the third heat transfer plate 42. Have gaps α and β. The length of the three outlet ridges 51a, 51b, 51c is the same length as the short side of the second heat transfer plate 42, with the outlet ridge 51a on the front end side of the second heat transfer plate 42 being the longest formed. That is, the farther from the front end side of the second heat transfer plate 42, the shorter. The end of the exit ridge 51b farthest from the front end side of the second heat transfer plate 42 and the end of the exit ridge 51c farthest from the third are smooth on the ends of the two main ridges 49, 49. Are connected by circular arcs.
[0037]
  On the inner and outer edges of the second heat transfer plate 42 corresponding to the inner and outer peripheral portions of the annular heat exchanger HE, convex portions 54 and 55 bent to the one side surface, and the convex portions Part 54, 55Front ofThe joint portions 56 and 57 bent to the other side surface are formed respectively. The height of the convex portions 54 and 55 is set equal to the height of the second ridges 48.The tip portion directly contacts the other side surface of the first heat transfer plate 41.The The joint portions 56 and 57 of the second heat transfer plate 42 are overlapped so as to partially overlap the inner surfaces of the joint portions 46 and 47 of the first heat transfer plate 41.
[0038]
  If the first heat transfer plate 41 and the second heat transfer plate 42 are arranged radially, the interval between the adjacent first and second heat transfer plates 41 and 42 is narrowed in the inner peripheral portion of the annular heat exchanger HE. In the outer peripheral portion, the interval is widened, but as is apparent from FIGS. 5 and 6, the first heat transfer plate 41 and the second heat transfer plate 42 are curved in an involute curve, whereby a heat exchanger is obtained. The distance between the first and second heat transfer plates 41 and 42 adjacent to each other at the inner and outer peripheral portions of the HE can be made uniform. However, since the first heat transfer plate 41 and the second heat transfer plate 42 are curved in an involute curve shape, the first and second heat transfer plates 41 and 42 are connected to the inner casing 44 at the inner peripheral portion of the heat exchanger HE. However, the outer casing 43 intersects at an acute angle.
[0039]
  As apparent from FIGS. 3 and 4, the first heat transfer plate 41 and the second heat transfer plate 42 which are alternately overlapped and combined in an annular shape are arranged on the front outer ring 58 and the front outer ring 58 on the front outer periphery and the rear outer periphery, respectively. And the rear outer ring 59 is fitted, and the front inner ring 60 and the rear inner ring 61 are fitted and positioned on the front inner periphery and the rear inner periphery, respectively. The outer casing 43 that covers and seals the outer peripheral surfaces of the first heat transfer plate 41 and the second heat transfer plate 42 combined in an annular shape has a large-diameter portion 43a at the front end fitted into the outer peripheral surface of the front outer ring 58. The compressed air inlet 19 opens between the rear end and the rear outer ring 59. Further, the inner casing 44 that covers and seals the inner peripheral surfaces of the first heat transfer plate 41 and the second heat transfer plate 42 has a rear-end enlarged-diameter portion 44a fitted to the inner peripheral surface of the rear inner ring 61, A compressed air outlet 20 opens between the front end and the front inner ring 60.
[0040]
  Thus, after integrating the 1st heat exchanger plate 41 and the 2nd heat exchanger plate 42 with the front outer ring 58, the rear outer ring 59, the front inner ring 60, and the rear inner ring 61, the outer peripheral surface and inner peripheral surface Since the outer casing 43 and the inner casing 44 are joined to each other, not only the assembly of the heat exchanger HE having the multiple first heat transfer plates 41 and the second heat transfer plates 42 is facilitated, but also the assembly accuracy is improved. it can. In addition, by joining the outer casing 43 and the inner casing 44, it is possible to more effectively prevent the compressed air from blowing through the outer peripheral surface and the inner peripheral surface of the first heat transfer plate 41 and the second heat transfer plate 42.
[0041]
  The first heat transfer plate 41, the second heat transfer plate 42, the front outer ring 58, the rear outer ring 59, the front inner ring 60, the rear inner ring 61, the outer casing 43 and the inner casing 44 are joined by brazing. As is clear from FIG. 5, in the portion where the first heat transfer plate 41 and the second heat transfer plate 42 are brazed to the inner casing 44, the narrow joint 46 of the first heat transfer plate 41 is the second heat transfer plate 41. It overlaps with a part of the outer surface of the wide joint portion 56 of the heat plate 42 so that most of the joint portion 56 of the second heat transfer plate 42 corresponds to the thickness of the first heat transfer plate 41. It faces the outer peripheral surface of the inner casing 44 through a gap. Therefore, it is possible to securely braze the brazing material shown in black by flowing in the gap, thereby ensuring the assembly strength of the heat exchanger HE and preventing the compressed air and combustion gas from being blown out.
[0042]
  Similarly, as is clear from FIG. 6, in the portion where the first heat transfer plate 41 and the second heat transfer plate 42 are brazed to the outer casing 43, the narrow joint portion 47 of the first heat transfer plate 41 is The second heat transfer plate 42 is overlapped with a part of the outer surface of the wide joint portion 57 so that most of the joint portion 57 of the second heat transfer plate 42 is the plate of the first heat transfer plate 41. It faces the inner peripheral surface of the outer casing 43 through a gap corresponding to the thickness. Therefore, it is possible to securely braze the brazing material shown in black by flowing in the gap, thereby ensuring the assembly strength of the heat exchanger HE and preventing the compressed air and combustion gas from being blown out.
[0043]
  In particular, since the inner edges of the first heat transfer plate 41 and the second heat transfer plate 42 that are curved in an involute curve intersect the outer peripheral surface of the inner casing 44 at a substantially right angle, the first heat transfer plate 41 and the second heat transfer plate 41 It becomes possible to laminate the plates 42 with high accuracy, and it is possible to effectively prevent brazing of compressed air from the high-pressure fluid passages 63... Described later to the low-pressure fluid passages 62.
[0044]
  As apparent from FIG. 3, the combustion gas inlet 21 and the combustion are disposed between one side surface of the first heat transfer plate 41 from which the first protrusions 45 project and the other side surface of the flat second heat transfer plate 42. In order to connect the gas outlet 22, a plurality of linear and parallel low-pressure fluid passages 62 partitioned by the first ridges 45 are defined.
[0045]
  As is apparent from FIG. 4, the compressed air inlet 19 and the compressed air are provided between one side surface of the second heat transfer plate 42 from which the second ridges 48 project and the other side surface of the flat first heat transfer plate 41. High-pressure fluid passages 63 are formed to connect the air outlet 20. The high-pressure fluid passages 63 are formed in a crank shape having inlet fluid passages 65a and 65b, main fluid passages 64, and outlet fluid passages 66a and 66b partitioned by the second ridges 48. That is, inlet fluid passages 65a and 65b extending radially inward from the compressed air inlet 19 are formed between the inlet ridges 50a, 50b and 50c, and the main fluid passage 64 extending in the axial direction between the main ridges 49. And outlet fluid passages 66a, 66b extending radially outward from the compressed air outlet 20 are formed between the outlet ridges 51a, 51b, 51c.
[0046]
  The main fluid passages 64 of the high-pressure fluid passages 63 that exchange heat with the low-pressure fluid passages 62 are formed in a substantially parallelogram shape as indicated by a chain line in FIG. 4, and therefore, the inlet fluid passages 65a and 65b. And while ensuring the space of the exit fluid passages 66a and 66b, the heat transfer area for heat exchange (the area of the main fluid passages 64) can be increased to the maximum to increase the heat exchange efficiency.
[0047]
  Thus, the relatively high-temperature and low-pressure combustion gas generated in the single can combustor 24 and driving the turbine wheel 17 passes through the combustion gas passage 31 and from the combustion gas inlet 21 at the front end of the heat exchanger HE to the low-pressure fluid passage. 62, and is discharged from the combustion gas outlet 22 at the rear end of the heat exchanger HE. On the other hand, the relatively low-temperature and high-pressure compressed air compressed by the compressor wheel 16 flows rearward through the first compressed air passage 12 formed on the outer periphery of the gas turbine engine E, and then the outer periphery of the rear end of the heat exchanger HE. From the compressed air inlet 19 formed in the section, it changes in the 90 ° direction inward in the radial direction and flows into the inlet fluid passages 65a and 65b, and then changes the 90 ° direction and flows forward through the main fluid passages 64. The compressed air is further turned 90 ° radially inward at the front end of the main fluid passage 64... And discharged from the compressed air outlet 20 formed at the inner peripheral portion of the front end of the heat exchanger HE to the second compressed air passage 28. Is done.
[0048]
  Thus, the heat exchanger HE includes the low-pressure fluid passages 62 and the high-pressure fluid passages 63 that are alternately formed between the first heat transfer plate 41 and the second heat transfer plate 42, and the high-temperature combustion gas is a low-pressure fluid. Since the low-temperature compressed air flows through the high-pressure fluid passage from the rear to the front through the passage 62 ... from the front to the rear, a so-called cross flow state is realized and the combustion gas and the compression are compressed over the entire axial length of the heat exchanger HE. The temperature difference between the air can be kept large and the heat exchange efficiency can be improved.
[0049]
  By the way, the compressed air flowing backward through the first compressed air passage 12 swivels 180 ° (see arrow A in FIG. 1) in the inlet fluid passages 65a and 65b of the heat exchanger HE, and then the main fluid passage 64 of the heat exchanger HE. ... Flows forward, but the compressed air is urged outward in the swirl direction by the centrifugal force acting during the swirl, and therefore, among the many main fluid passages 64 formed in parallel along the axial direction, The amount of compressed air supplied to the main fluid passage 64 on the outer side in the swirling direction, that is, the main fluid passage 64 on the radially inner side of the heat exchanger HE increases, and conversely, the main fluid passage on the outer side in the radial direction of the heat exchanger HE. 64 tends to decrease the amount of compressed air supplied to.
[0050]
  However, according to the present embodiment, among the inlet fluid passages 65a and 65b defined by the three inlet ridges 50a, 50b, and 50c, the width Wa of the inlet fluid passage 65a on the outer side in the turning direction is narrowed and the turning direction is set. The width Wb of the inner inlet fluid passage 65b is widened, and the end of the inlet ridge 50b farthest from the rear end side of the second heat transfer plate 42 and the end of the inlet ridge 50c farthest from the third heat transfer plate 42 are , The gaps α and β are provided between the ends of the main ridges 49, and the lengths of the main ridges 49 are not uniform. Therefore, the amount of compressed air flowing into all the main fluid passages 64 can be made uniform regardless of the position in the radial direction.
[0051]
  The reason is that the width Wa of the inlet fluid passage 65a on the outer side in the swirl direction in which the flow rate of compressed air tends to increase due to centrifugal force is narrowed, and conversely, the inlet fluid passage on the inner side in the swirl direction in which the flow rate of compressed air tends to decrease. By increasing the width Wb of 65b, the amount of compressed air distributed from the inlet fluid passages 65a, 65b to the main fluid passages 64 can be made uniform. In addition, the downstream ends of the two inlet ridges 50b and 50c are not connected to the upstream ends of the main ridges 49 and 49, so that gaps α and β are formed, and the positions of the front and rear ends of the main ridges 49 are Since it is adjusted in the front-rear direction, the distribution amount of compressed air in the main fluid passages 64 can be more effectively uniformized.
[0052]
  On the other hand, the two main ridges 49, 49 are smoothly connected to the two outlet ridges 51b, 51c, and the widths Wc, Wd of the two outlet fluid passages 66a, 66b are set not to be the same. Therefore, the compressed air flowing through the main fluid passages 64 can be smoothly guided to the outlet fluid passages 66a and 66b to minimize the occurrence of pressure loss.
[0053]
  Since the main fluid passage 64, the inlet fluid passages 65a and 65b, and the outlet fluid passages 66a and 66b are configured as described above, the compressed air is uniformly distributed over the entire crank-shaped bent high-pressure fluid passage 63 as a whole. And it becomes possible to flow smoothly.
[0054]
  Further, since the pressure of the compressed air flowing through the high-pressure fluid passages 63 is higher than the pressure of the combustion gas flowing through the low-pressure fluid passages 62, the first low-pressure fluid passage 62 that is sandwiched between the adjacent high-pressure fluid passages 63, 63 is defined. The heat transfer plate 41 and the second heat transfer plate 42 receive a load in a direction approaching each other due to a pressure difference between the compressed air and the combustion gas. However, by supporting the other side surface of the second heat transfer plate 42 with a plurality of first ridges 45 projecting from one side surface of the first heat transfer plate 41 at a small pitch, the pressure difference between the compressed air and the combustion gas is increased. Therefore, it is possible to reliably prevent the first heat transfer plate 41 and the second heat transfer plate 42 from being deformed. Moreover, since the first ridges 45 are formed by continuously bending the first heat transfer plate 41 at a predetermined interval and bringing the bent portions into close contact with each other, the thickness of the portion is doubled and the pressure is increased. Not only can the rigidity to support the difference be increased, but the processing cost can be greatly reduced.
[0055]
  The first heat transfer plate 41 and the second heat transfer plate 42 that define the high pressure fluid passage 63 sandwiched between the adjacent low pressure fluid passages 62 and 62 are separated from each other by the pressure difference between the compressed air and the combustion gas. Therefore, even if the pitch of the second ridges 48 of the second heat transfer plate 42 arranged inside the high-pressure fluid passage 63 is set to be rough, no problem in strength occurs. Therefore, it is sufficient to form the second ridges 48... At a pitch that can maintain the distance between the first heat transfer plate 41 and the second heat transfer plate 42, which reduces the processing cost and weight of the second heat transfer plate 42. Can contribute.
[0056]
  Further, convex portions 54 and 55 projecting from the inner and outer edges of one side surface of the second heat transfer plate 41.Front ofOn the other side of the first heat transfer plate 42DirectlySince they are in contact with each other, the distance between the inner and outer edges of the first and second heat transfer plates 41 and 42 can be made equal to the set value without requiring a special spacer or the like.
[0057]
  8 and 9 show a second embodiment of the present invention. FIG. 8 is a perspective view of the heat exchanger, and FIG. 9 is a view in the direction of arrow 9 in FIG.
[0058]
  The heat exchanger HE of the first embodiment described above is formed in an annular shape, whereas the heat exchanger HE of the second embodiment is formed in a rectangular parallelepiped shape. The structure of the first heat transfer plate 41 and the second heat transfer plate 42 is substantially the same as that of the first embodiment, but the first and second heat transfer plates 41, 42 of the first embodiment are involute curves. In contrast, the first and second heat transfer plates 41 and 42 of the second embodiment are formed in a flat shape.
[0059]
  One side edge of the alternately stacked first and second heat transfer plates 41 and 42 is joined to an end plate 43 ′ corresponding to the outer casing 43, and the other side edge is an end corresponding to the inner casing 44. Joined to plate 44 '. A pair of side plates 71 and 72 are joined to both surfaces of the first and second heat transfer plates 41 and 42 in the stacking direction. Since the side edges of the first and second heat transfer plates 41 and 42 and the both end plates 43 'and 44' intersect at right angles, the side edges of the first and second heat transfer plates 41 and 42 in the first embodiment It joins by the same structure as a junction part with the inner casing 43 (refer FIG. 9). The high-temperature combustion gas flows in from the combustion gas inlet 21 at the front end of the heat exchanger HE and flows out from the combustion gas outlet 22 at the rear end, and the low-temperature compressed air is compressed air formed at the rear end of one end plate 43 '. It flows in from the inlet 19 and flows out from the compressed air outlet 20 formed at the front end of the other end plate 44 '.
[0060]
  Thus, the second embodiment can provide the same operational effects as the first embodiment, and the heat exchanger HE can be made compact.
[0061]
  As mentioned above, although the Example of this invention was explained in full detail, this invention can perform a various design change in the range which does not deviate from the summary.
[0062]
【The invention's effect】
  As described above, according to the first aspect of the present invention, the plate body is continuously bent at a predetermined interval, and the bent portion is brought into close contact with each other so as to be parallel to one side surface of the first heat transfer plate. Since the first ridge is formed, when one side of the first heat transfer plate and the other side of the second heat transfer plate are joined to form a low pressure fluid passage, the high pressure fluid located on both sides of the low pressure fluid passage Even if the pressure from the passage acts on the first heat transfer plate and the second heat transfer plate, the first and second heat transfer plates can be prevented from being deformed by supporting the pressure with a plurality of first protrusions. it can. Moreover, since the first ridge is formed by bending the first heat transfer plate, it is not only low in cost, but also has a high strength because it has twice the thickness of the first heat transfer plate. . On the other hand, since the second ridges of the second heat transfer plate located in the high-pressure fluid passage do not need to support the pressure, there is no problem even if the number thereof is smaller than the number of the first ridges. 2 It can contribute to the reduction of the processing cost and weight of the heat transfer plate.
[0063]
  AlsoA convex portion formed on the both side edges of the second heat transfer plate by bending to one side surface of the second heat transfer plate and having a tip directly contacting the other side surface of the first heat transfer plate; And a joint formed by bending the other end side than the tip is provided.Joining formed by bending both side edges of the first heat transfer plate to one sidePartSince they are overlapped and joined, both side edges of the high-pressure fluid passage defined between the first and second heat transfer plates can be reliably sealed to prevent the high-pressure fluid from being blown out.At the same time, the tip of the convex portion protruding from the inner edge and the outer edge of one side surface of the second heat transfer plate can be brought into contact with the other side surface of the first heat transfer plate, so that a special spacer or the like is required. The mutual interval between the inner and outer edges of the first and second heat transfer plates can be matched with the set value.
[0064]
  And claims2According to the invention described in the above, in the state where the first and second heat transfer plates stacked in an annular shape are fixed and positioned by four rings, the outer casing is respectively provided on the radially outer edge and the radially inner edge. Since the inner casing and the inner casing are joined and sealed, it is possible not only to easily and precisely assemble a heat exchanger having a large number of first and second heat transfer plates, but also from a high pressure fluid passage to a low pressure fluid passage. The outer casing and the inner casing can more reliably prevent the high-pressure fluid from being blown through the outer casing.
[0065]
  And claims3Since the first heat transfer plate and the second heat transfer plate are curved in an involute curve, the distance between the first and second heat transfer plates at each position in the radial direction of the heat exchanger is described. Can be made uniform.
[0066]
  And claims4According to the invention described in the first and second heat transfer plates, the joint portions of the side edges of the first and second heat transfer plates are arranged along the outer peripheral surface of the inner casing and the inner peripheral surface of the outer casing. The joint portion and both casings can be joined with high accuracy and without any gaps, thereby effectively preventing the high pressure fluid from being blown through.
[0067]
  And claims5According to the invention described in (1), since the radially inner edges of the first and second heat transfer plates are orthogonal to the outer peripheral surface of the inner casing, the first and second heat transfer plates can be stacked with high accuracy. In addition, the accuracy of joining to the inner casing is improved.
[0068]
  And claims6According to the invention described in the above, the heat exchanger can be configured in a rectangular parallelepiped shape to be compact.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a gas turbine engine.
2 is an enlarged sectional view taken along line 2-2 of FIG.
3 is an enlarged sectional view taken along line 3-3 in FIG.
4 is an enlarged sectional view taken along line 4-4 of FIG.
5 is an enlarged view of part 5 of FIG.
6 is an enlarged view of part 6 in FIG.
7 is a cross-sectional view taken along line 7-7 in FIG.
FIG. 8 is a perspective view of a heat exchanger according to a second embodiment.
9 is a view in the direction of arrow 9 in FIG.
[Explanation of symbols]
41 1st heat exchanger plate
42 Heat transfer plate
45 First ridge
46,47 joints
48 Second ridge
56,57 joints
58 Front outer ring
59 Rear outer ring
60 Front inner ring
61 Rear inner ring
62 Low pressure fluid passage
63 High-pressure fluid passage

Claims

A first heat transfer plate (41) in which a plurality of parallel first protrusions (45) are formed on one side surface by continuously bending the plate body at a predetermined interval and bringing the bent portion into close contact, and a plate body A heat exchanger in which a second heat transfer plate (42) in which a plurality of second ridges (48) having a smaller number than the first ridges (45) are formed on one side surface is alternately superposed,
A low-pressure fluid passage (62) partitioned by a plurality of first ridges (45) is formed between one side surface of the first heat transfer plate (41) and the other side surface of the second heat transfer plate (42), A high-pressure fluid passage (63) partitioned by a plurality of second protrusions (48) is formed between one side surface of the second heat transfer plate (42) and the other side surface of the first heat transfer plate (41). ,
The side edges of the second heat transfer plate (42) are formed by bending to one side of the second heat transfer plate (42), and the front part directly contacts the other side of the first heat transfer plate (41). A convex part (54, 55) and a joint part (56, 57) formed by bending the convex part (54, 55) to the other side surface from the tip part are provided, and the joint part (56, 57). ) and the heat exchanger joint the opposite side edges formed by bending on one side (46, 47) and is characterized Rukoto are superposed and joined together in the first heat transfer plate (41).

The first heat transfer plate (41) and the second heat transfer plate (42) are laminated in an annular shape, and the radially outer edge and the radially inner edge of the front end in the axial direction of the first and second heat transfer plates (41, 42). The front outer ring (58) and the front inner ring (60) are fixed to the edges, respectively, and the radially outer edge and the radially inner edge of the axial rear end of the first and second heat transfer plates (41, 42) are fixed. After fixing the rear outer ring (59) and the rear inner ring (61), respectively, the outer casing (43) and the radial outer edge and the radial inner edge of the first and second heat transfer plates (41, 42), respectively. wherein the sealing by joining the inner casing (44), the heat exchanger according to claim 1.

Characterized in that curved first heat transfer plate (41) and the second heat transfer plate (42) to the involute curve shape, the heat exchanger according to claim 2.

The joint portions (46, 56) at the radially inner edges of the first and second heat transfer plates (41, 42) are arranged along the outer peripheral surface of the inner casing (44), and the first and second heat transfer plates (41). The heat exchanger according to claim 3 , characterized in that the joint portion (47, 57) of the radially outer edge of the outer casing (43) extends along the inner peripheral surface of the outer casing (43).

The heat exchanger according to claim 4 , wherein the radially inner edges of the first and second heat transfer plates (41, 42) are orthogonal to the outer peripheral surface of the inner casing (44).

The heat exchanger according to claim 1, wherein the first heat transfer plate (41) and the second heat transfer plate (42) formed in a flat plate shape are stacked in a rectangular parallelepiped shape.