JP4428305B2 - Ship exhaust system - Google Patents

Description

  The present invention relates to a ship exhaust device, and more particularly, to measures for reducing exhaust gas back pressure and noise.

  Conventionally, as a ship exhaust device, a silencer that introduces exhaust gas from an internal combustion engine through an exhaust passage is provided, and an exhaust pipe connected to the upstream end of the exhaust pipe and opened above the water line is connected to the silencer. A device is known in which exhaust gas is discharged out of the hull from the downstream end (see, for example, Patent Document 1).

  In addition, as other ship exhaust devices, at the downstream end of an exhaust pipe for exhausting exhaust gas from the internal combustion engine to the outside of the hull, a low-speed exhaust port that protrudes downward from the constant water line and opens in water, and a constant water line A high-speed exhaust port with a lid that can be opened and closed is opened when exhaust gas is discharged, and exhaust gas from the low-speed exhaust port is discharged into the water at low speed, while high speed at high speed. Some exhaust gas from the time exhaust port is discharged to the atmosphere by opening the lid (see, for example, Patent Document 2).

  Further, as another ship exhaust device, an exhaust gas from the internal combustion engine is exhausted from the first and second exhaust expansion chambers into the water through the main exhaust passage, and a sub exhaust passage branched from the main exhaust passage is provided. In some cases, the air is discharged into the air surrounded by the concave portion outside the hull and the water line (for example, see Patent Document 3). Then, a projecting guide part protrudes into the water on the bow side of the exhaust port that opens in the main exhaust passage, and the guide part causes a water flow that moves downward along with the draft line at a high speed forward from the periphery of the exhaust port. By detouring, the exhaust gas from the exhaust port is sucked and discharged into the negative pressure space formed between the water flow detoured from the periphery of the exhaust port by the guide portion and the exhaust port when moving forward at high speed. I have to.

On the other hand, as an exhaust device for other ships, an exhaust mixing chamber that mixes cooling water such as seawater with exhaust gas from the internal combustion engine is provided in the middle of the exhaust pipe, and the exhaust gas that is hot in the exhaust mixing chamber is provided. There is also one that is mixed with cooling water for cooling (for example, see Patent Document 4).
JP-A-11-342895 Japanese Utility Model Publication No. 58-56110 Japanese Patent No. 3066648 Utility Model Registration No. 2549229

  However, when the exhaust pipe is discharged into the air outside the hull (above the water surface) in the conventional silencer (the one disclosed in Patent Document 1), the back pressure of the exhaust gas is increased by the silencer and the output is increased. The performance must be compromised to some extent. In addition, in the case of discharging seawater in the exhaust pipe for the purpose of lowering the temperature of the exhaust gas (seawater mixing) (Patent Document 4), water is discharged into the air together with the exhaust gas, and bubbles are generated on the water surface. It is not suitable for fishing.

  In addition, when exhaust gas is discharged into the water, the exhaust pipe or the guide part protruding from the water (Patent Document 2 or Patent Document 3) becomes a resistance to water flow, resulting in deterioration of fuel consumption or speed reduction. Cause.

  The present invention has been made in view of the above points, and an object of the present invention is to suppress an increase in exhaust gas back pressure, to prevent generation of bubbles on the water surface when exhaust gas is discharged, and to improve fuel efficiency. An object of the present invention is to provide a ship exhaust device that can reliably prevent deterioration and speed reduction.

  In order to achieve the above object, according to the present invention, a chamber for introducing exhaust gas of an internal combustion engine through an exhaust pipe is provided on the stern side of a ship body as an exhaust device of a ship, and the chamber is provided with a draft line at a low speed. A first exhaust port that opens upward, a second exhaust port that opens below the water line at low speeds, and an opening that opens to the bow side of the second exhaust port and continues into the chamber. And a guide member that guides the wall from the periphery of the second exhaust port so as to detour the water flow on the water line that moves downward when traveling at high speed. The exhaust gas from the first exhaust port is discharged from a low speed including an idling time to a high speed, while the exhaust gas from the second exhaust port is discharged from the guide during the high speed advance. The negative pressure space formed between the water flow detoured from the periphery of the second exhaust port and the second exhaust port by the wall portion of the member is sucked and discharged.

  Due to this specific matter, the exhaust gas in the chamber introduced from the internal combustion engine is smoothly discharged into the air from the first exhaust port above the water line during idling or low speed advance. Then, the guide member having a wall portion that is continuous toward the inside of the chamber from the opening portion that opens to the bow side of the second exhaust port causes the water flow at the water line that moves downward during high-speed advancement to flow in the second exhaust port. The exhaust gas in the chamber is sucked and smoothly discharged during high-speed advancement with respect to the negative pressure space between the bypassed water flow and the second exhaust port. As a result, the exhaust gas introduced into the chamber from the internal combustion engine is smoothly discharged from each exhaust port and the back pressure does not increase, and the output performance is not sacrificed as in the case where a silencer is provided. . In addition, exhaust gas from the internal combustion engine is introduced into the chamber whose volume is expanded, so that exhaust noise from each exhaust port can be reduced.

  Also, even if water enters the chamber from the exhaust pipe by seawater mixing, bubbles are eliminated in the chamber and the exhaust gas is not discharged into the air from the first exhaust port. When the vehicle moves forward, only the exhaust gas is discharged from the first exhaust port, so that the generation of bubbles on the water surface is prevented and fishing and the like can be performed smoothly.

  In addition, the wall portion of the guide member that guides the water flow so as to be diverted from the periphery of the second exhaust port is continuous toward the inside of the chamber from the opening that opens closer to the bow side than the second exhaust port. As a result, the wall portion of the guide member does not become a resistance to water flow unlike the exhaust pipe and the guide portion protruding from the hull, and it becomes possible to reliably prevent deterioration of fuel consumption and speed reduction.

  Furthermore, by providing a chamber for introducing the exhaust gas of the internal combustion engine through the exhaust pipe and exhausting the introduced exhaust gas from the first and second exhaust ports, the stormy weather that receives waves from the rear and the side is provided. Even when a wave enters the chamber from the first and second exhaust ports at the time of retreating or retreating, it is avoided that the momentum of the wave is buffered in the chamber and directly acts on the exhaust pipe. It is possible to prevent the backflow of seawater.

  In particular, the following configurations are listed as specifying the opening of the guide member.

  That is, the opening of the guide member is also used as a third exhaust port communicating with the inside of the chamber through the wall.

  With this specific matter, the exhaust gas in the chamber is also discharged from the third exhaust port during high-speed advance, and the exhaust efficiency in the chamber can be increased.

  In particular, the following configuration is listed as a means for smoothly discharging exhaust gas during retreat.

  That is, the stern of the hull is made to stand at an acute angle with respect to the draft line so as to guide the water flow along the draft line that moves downward when retreating and to bypass each of the first and second exhaust openings. The exhaust gas from the first exhaust port is exhausted into the air by the water flow that is detoured from the periphery of the first exhaust port by the stern when retreating, while the exhaust gas from the second exhaust port is discharged. Are sucked into a negative pressure space formed between the second exhaust port and the water flow diverted from the periphery of the second exhaust port by the stern during retreat.

  Due to this specific matter, the exhaust gas in the chamber introduced from the internal combustion engine at the time of reverse travel is smoothly discharged from the first exhaust port into the air by the water flow diverted from the periphery of the first exhaust port by the stern at the time of reverse operation. . Then, exhaust gas from the second exhaust port is smoothly sucked into the negative pressure space formed between the water flow diverted from the periphery of the second exhaust port by the stern at the time of reverse and the second exhaust port. Discharged. As a result, the exhaust gas in the chamber can be smoothly discharged from each exhaust port even when retreating, and an increase in back pressure can be suppressed.

  In particular, the following configurations are listed as specifying the second exhaust port and the opening of the guide member.

  That is, the second exhaust port and the opening of the guide member are respectively provided on the lower surface of the chamber, connected to the lower end of the tubular object protruding upward from the lower surface of the chamber, and the wall of the guide member is connected to the opening. It is formed by a tubular object.

  Due to this specific matter, the second exhaust port and the opening of the guide member are secured in the vertical dimension into the chamber by a tubular object that projects upward by connecting the lower end thereof. Thereby, when the water flow that moves downward together with the water line during high-speed advance is diverted from the periphery of the second exhaust port by the wall portion of the guide member, water enters the chamber from the second exhaust port or the opening. It is effectively prevented by the upward raising by the tubular object. In addition, when the water flow is diverted from the periphery of the second exhaust port by the stern at the time of retreat, the intrusion of water into the chamber from the second exhaust port or the opening is effectively prevented by raising the tube upward. Is done. Moreover, the exhaust sound from the second exhaust port and the opening of the guide member can be reduced by the tubular object.

  Furthermore, when the downstream end of the exhaust pipe of the generator mounted in the hull is connected to the chamber, bubbles are processed in the chamber when exhaust gas is discharged from the generator, and only the exhaust gas is discharged. In addition, the exhaust gas from the generator is introduced into the chamber with the expanded volume, and the exhaust noise can be reduced.

In short, the exhaust gas from the internal combustion engine is introduced into the chamber, and the water flow at the waterline that moves downward when the vehicle moves forward at high speed continues from the opening opening to the bow side of the second exhaust port toward the chamber. By guiding the wall of the guide member to bypass the second exhaust port, the exhaust gas in the chamber is smoothly discharged from the first and second exhaust ports to suppress an increase in back pressure. In addition, exhaust gas can be introduced into the chamber whose output performance is improved and the volume is expanded to reduce the exhaust noise from each exhaust port. In addition, bubbles can be eliminated in the chamber, and only exhaust gas can be discharged from the first exhaust port during idling or when moving forward at a low speed to prevent generation of bubbles on the surface of the water, so that fishing can be performed smoothly. In addition, by making the wall portion of the guide member continuous from the opening toward the inside of the chamber, it is possible to reliably prevent deterioration in fuel consumption and speed reduction without causing the wall portion of the guide member to resist water flow. Furthermore, by providing the chamber, the force of waves entering from the first and second exhaust ports during stormy weather or retreating is buffered in the chamber and does not directly act on the exhaust pipe, Seawater backflow can be prevented.

  The best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a side view in which a part of a cruiser-type ship provided with an exhaust device according to an embodiment of the present invention is cut away. In the vicinity of the center of a hull 10 of this ship 1, two left and right internal combustion engines 2 are disposed. (Only one is shown in FIG. 1) is mounted, and the left and right propellers 21 (only one is shown in FIG. 1) are individually rotated by each internal combustion engine 2 to navigate the ship 1. Between each internal combustion engine 2 and the propeller 21, there is provided a gear device 22 in which a forward / reverse switching gear, a reduction gear, a ship speed switching transmission, and a clutch (not shown) are incorporated.

  An upstream end of an exhaust pipe 3 (only one is shown in FIG. 1) is connected to the exhaust port 20 of each internal combustion engine 2, and each exhaust pipe 3 has a stern (see FIG. 1 extends to the left). Further, as shown in FIG. 2, chambers 4 are respectively provided on the left and right sides of the stern in the hull 10. Each of the chambers 4 has a substantially rectangular thin box shape that is thin in the left / right side and long in the front / rear direction of the hull. Further, the downstream end of the exhaust pipe 3 is connected to a substantially central position of the front surface of each chamber 4 so that the exhaust gas from each internal combustion engine 2 is introduced into the chamber 4.

  Further, as shown in FIG. 3, each chamber 4 is provided along the left and right sides of the stern, and the stern side upper portion of the outer surface (the left and right sides) is drained at idling and at low speed. A first exhaust port 41 is sometimes provided that opens above the waterline S1. As shown in FIG. 4, the first exhaust port 41 opens to the outside of the hull 10 (the shore side) above the draft line S <b> 1 when draining, and obliquely forwards from the outer surface of the chamber 4 into the chamber 4. It is connected to the outer end of the first circular tubular member 41A that protrudes toward the bottom. At the outer end of the first tubular object 41A, a rod 41A1 having a front arcuate portion protruding outward from the hull 10 (left and right rod sides) is provided. In addition, the lower surface of the chamber 4 is provided with a second exhaust port 42 that opens below the water line S1 during drainage such as when idling or at low speed. This second exhaust port 42 opens to the lower surface of the hull 10 and is connected to the lower end of a second circular tubular object 42A (tubular object) that projects obliquely upward and forward from the lower surface of the chamber 4 into the chamber 4. Has been. Further, an opening 43 is provided on the lower surface of the chamber 4 so as to open below the water line S1 during drainage on the bow side (front side) of the second exhaust port 42. The opening 43 opens to the lower surface of the hull 10 on the bow side of the second exhaust port 42, and serves as a third guide member that projects obliquely upward and forward from the lower surface of the chamber 4 into the chamber 4. It is connected to the lower end of the circular tubular product 43A. In this case, the upstream end (inner end) of the third tubular object 43A communicates with the inside of the chamber 4 in the same manner as the first and second circular objects 41A, 42A, and the opening 43 has the first end. 3 as an exhaust port 43.

And the 3rd tubular object 43A makes the water flow in draft line S2 (it shows with a dashed-two dotted line in FIG. 3) which changes below at the time of sliding, such as at the time of high speed advance, to detour from the circumference | surroundings of the 2nd exhaust port 42. The wall 43A1 is a part of the third circular tube 43A that continues from the opening 43 (hereinafter referred to as the third exhaust port 43) into the chamber 4 (rear side). A semicircular arc section located on the side). The second tubular object 42A is attached in a forward tilted state in which its central axis is tilted forward at an angle of approximately 45 ° with respect to the draft line S2, while the third circular tubular object 43A has its central axis. It is attached in a forward tilted state tilted approximately 30 ° obliquely forward with respect to the waterline S2. The exhaust gas from the first exhaust port 41 is
It is discharged to the outside of the ship from the time of drainage (low speed including idling) to the time of sliding (high speed forward). On the other hand, the exhaust gas from the second exhaust port 42 is formed between the second exhaust port 42 and the water flow detoured from the periphery of the second exhaust port 42 by the wall portion 43A1 of the third circular tube 43A during sliding. The negative pressure space H1 formed therebetween is sucked and discharged. In this case, the exhaust gas from the third exhaust port 43 is discharged into the water when it cannot be exhausted from the first and second exhaust ports 41 and 42.

  Further, as shown in FIGS. 1 and 2, the stern of the hull 10 guides the water flow at the draft line S3 ′ that moves downward due to contact with the stern when retreating, so that the first and second exhaust ports 41, It stands up at an acute angle with respect to the waterline S3 ′ so as to be detoured from around 42 respectively. And as shown in FIG. 5, the exhaust gas from the 1st exhaust port 41 is discharged | emitted in the air by diverting a water flow from the circumference | surroundings of the 1st exhaust port 41 by the stern at the time of reverse. . On the other hand, the exhaust gas from the second exhaust port 42 flows in the water flow diverted from the periphery of the second exhaust port 42 by the contact with the stern at the time of retreat (the water line S3 ′ that changes downward by the contact with the stern). In the negative pressure space H2 formed between the second exhaust port 42 and the second exhaust port 42. In addition, S3 of FIG. 5 has shown the waterline which does not contact | abut the stern at the time of reverse.

  As shown in FIG. 3, when the ship 1 is semi-sliding at a medium speed of about 10 to 15 knots, the draft line S4 rises more than the draft line S1 during drainage and the first exhaust port 41 is waved. Therefore, the water flow is diverted from the periphery of the first exhaust port 41 by the flange 41A1 of the first circular tubular object 41A during the semi-sliding, and formed between the detoured water flow and the first exhaust port 41. The exhaust gas from the first exhaust port 41 is sucked into the negative pressure space H3 (shown in FIG. 4) to be discharged.

  Further, as shown in FIG. 2, a generator 5 is mounted at the stern side in the hull 10, specifically, at the center of the hull located on the front side or side of the chamber 4. An exhaust pipe 51 is provided on the left side of the generator 5. The exhaust pipe 51 is connected to the lower surface of the generator 5 at its upstream end, rises upward with a curved portion 51 a from below the generator 5, and has a bent portion 51 b at the upper portion of the generator 5, and is ported. It extends obliquely downward toward the side, and the downstream end is led out at a substantially central position on the inner surface of the chamber 4 on the port side. In this case, the downstream end of the exhaust pipe 51 is attached in a state of protruding into the chamber 4 at a position above the draft line S1 during drainage, whereby power generation by the engine pressure of the internal combustion engine 2 from the exhaust pipe 3 is performed. An increase in the back pressure of the machine 5 can be avoided. Further, the upstream end of the exhaust pipe 51 is connected to the generator 5 at a position lower than the downstream end in order to prevent backflow of seawater to the generator 5 through the exhaust pipe 51.

  Here, when exhaust gas is exhausted from the exhaust ports 41 to 43 through the chamber 4, exhaust gas is exhausted through a silencer in the middle of the exhaust pipe, and exhaust gas is exhausted. The characteristics of the back pressure and noise when exhaust gas is discharged without a silencer in the middle of the pipe will be described with reference to FIGS.

  First, as shown in FIG. 6, the characteristics of the exhaust gas back pressure with respect to the rotational speed of the internal combustion engine 2 are compared with the case without a silencer without a silencer as compared with the case with a silencer with a silencer. In the case of the present invention having the chamber 4 with the exhaust gas having a lower back pressure, the back pressure is slightly higher than that without the silencer. The exhaust gas from the second exhaust port 42 is detoured from the periphery of the second exhaust port 42 by the wall 43A1 of the third tubular object 43A from the vicinity where the number exceeds 3200 rpm and shifts to the medium-high speed forward state. Since the negative pressure space H1 formed between the generated water flow and the second exhaust port 42 is sucked and discharged through the second circular tube 42A, the back pressure of the exhaust gas is greatly reduced. You can see that

Further, as shown in FIG. 7, the characteristics of the exhaust gas noise with respect to the rotational speed of the internal combustion engine 2 are lower when the silencer is provided than when the silencer is not provided. When the chamber 4 is provided as described above, it can be seen that the noise is further reduced as compared with the case where the silencer is provided. In particular, in the present invention, a great silencing effect is obtained until the low and medium speed forward state where the rotational speed of the internal combustion engine 2 is less than 2600 rpm.

  Therefore, in the above-described embodiment, the exhaust gas in the chamber 4 introduced from each internal combustion engine 2 via the exhaust pipe 3 is the first exhaust above the water line S1 during drainage such as idling or low speed advance. The air is smoothly discharged from the mouth 41 into the air. In addition, the draft line S4 rises more than the draft line S1 at the time of drainage during a semi-sliding that moves forward at a medium speed, and the first exhaust port 41 is waved. By diverting the water flow around the exhaust port 41, the exhaust gas from the first exhaust port 41 is sucked into the negative pressure space H3 formed between the detoured water flow and the first exhaust port 41. Are discharged smoothly. Then, the third circular tube 43A having a wall portion 43A1 continuous from the third exhaust port 43 that opens to the bow side of the second exhaust port 42 toward the inside of the chamber moves downward at the time of sliding at a high speed. The water flow at the changing waterline S2 is guided to be diverted from the periphery of the second exhaust port 42, and the chamber 4 is caused to slide in the negative pressure space H1 between the detoured water flow and the second exhaust port 42. The exhaust gas in the chamber is sucked and discharged smoothly, and the exhaust gas in the chamber 4 that could not be exhausted is exhausted into the water through the third exhaust port 43. As a result, the exhaust gas introduced into the chamber 4 from each internal combustion engine 2 is not smoothly exhausted from the exhaust ports 41 to 43 and the back pressure does not increase, and the output performance is as if a silencer was provided. The output performance can be improved without sacrificing. In addition, the exhaust gas from each internal combustion engine 2 through the exhaust pipe 3 is introduced into the chamber 4 whose volume has been expanded, and the first to third exhaust ports 41A to 43A are used to provide the first to third exhaust ports. Since the exhaust is discharged from 41 to 43, the exhaust sound from each of the exhaust ports 41 to 43 can be effectively reduced. Further, the second and third exhaust ports 42 and 43 have a vertical dimension in the chamber 4 secured by circular tubular objects 42A and 43A extending upward from the lower surface of the chamber 4, so that the second and third exhaust ports 42 and 43 are moved downward during the sliding. The chamber 4 from the second exhaust port 42 or the third exhaust port 43 when the water flow at the changing waterline S2 is diverted from the periphery of the second exhaust port 42 by the wall 43A1 of the third circular tube 43A. Intrusion of water into the inside can be effectively prevented by raising the upward by the circular tubular objects 42A and 43A.

  Further, even if water is discharged into the chamber 4 from each of the exhaust pipes 3 and 51, bubbles are eliminated in the chamber 4 and water together with the exhaust gas is not discharged into the air from the first exhaust port 41, Only the exhaust gas is discharged from the first exhaust port 41 at the time of drainage to prevent generation of bubbles on the water surface, and fishing can be performed smoothly.

  And wall part 43A1 which guides a water flow so that it may detour from the circumference | surroundings of the 2nd exhaust port 42 goes into the chamber 4 from the 3rd exhaust port 43 opened in the bow side rather than the 2nd exhaust port 42. Since it is constituted by a part of the continuous third circular tubular object 43A (a semicircular arc-shaped part located on the rear side), the third circular tubular object 43A like an exhaust pipe or a guide part protruding from the hull. The wall portion 43A1 does not become a resistance to water flow, and it is possible to reliably prevent deterioration of fuel consumption and speed reduction.

  Further, since the opening 43 of the third circular tubular body 43A is also used as a third exhaust port communicating with the chamber 4 through the wall 43A1, the exhaust in the chamber 4 is exhausted during sliding and semi-sliding. The gas is also discharged into the water from the third exhaust port 34 (opening 43), and the exhaust efficiency in the chamber 4 can be increased.

Then, the stern of the hull 10 is cut at an acute angle with respect to the draft line S3 so as to guide the water flow at the draft line S3 that moves downward when retreating, and to bypass each of the first and second exhaust ports 41 and 42, respectively. Thus, the exhaust gas from the first exhaust port 41 is smoothly discharged into the air by detouring the water flow from the periphery of the first exhaust port 41 by the stern when retreating, while the second exhaust port The exhaust gas from 42 is sucked into the negative pressure space H2 formed between the second exhaust port 42 and the water flow diverted from the periphery of the second exhaust port 42 by the stern at the time of reverse, and is smoothly discharged. As a result, the exhaust gas in the chamber 4 can be smoothly discharged from the exhaust ports 41 and 42 even when retreating, thereby suppressing an increase in back pressure. In addition, when the water flow is diverted from the periphery of the second exhaust port 42 by the stern at the time of retreat, the second and third intrusion of water into the chamber 4 from the second exhaust port 42 or the third exhaust port 43 is prevented. It can prevent effectively by the upward raising by 3rd circular tubular thing 42A, 43A.

  Moreover, since the downstream end of the exhaust pipe 51 of the generator 5 mounted in the hull 10 is connected to the port-side chamber 4, bubbles are processed in the chamber 4 when exhaust gas is discharged from the generator 5. Not only exhaust gas can be discharged, but also exhaust gas from the generator 5 can be introduced into the chamber 4 whose volume has been expanded to reduce exhaust noise.

  Further, the exhaust gas from each internal combustion engine 2 is introduced through the exhaust pipe 3, and waves are introduced from the rear and the sides by the chamber 4 that exhausts the introduced exhaust gas from the first to third exhaust ports 41 to 43. Even if a wave enters the chamber 4 from the first to third exhaust ports 41 to 43 during stormy weather or retreat, the force of the wave is buffered in the chamber 4 and directly into the exhaust pipes 3 and 51. The action is avoided, and the backflow prevention of seawater into the exhaust pipes 3 and 51 can be practiced.

  In addition, this invention is not limited to the said embodiment, The other various modifications are included. For example, in the above embodiment, the opening 43 of the third tubular object 43A is also used as the third exhaust port communicating with the chamber 4 through the wall 43A1, but the upper end of the third tubular object is It may be closed without communicating in the chamber, and even in this case, it is possible to guide the water flow on the water line that moves downward during the sliding so as to be diverted from the periphery of the second exhaust port by the wall portion. It becomes.

  Moreover, in the said embodiment, although wall part 43A1 was comprised by the cross-sectional semicircular arc-shaped part located in a part of 3rd tubular thing 43A, ie, the back side, the opening part opened to the bow side rather than the 2nd exhaust port Any wall portion may be used as long as the wall portion guides the water flow along the waterline that continues from the inside of the chamber toward the inside of the chamber and moves downward when moving forward at a high speed from the periphery of the second exhaust port.

  Furthermore, in the above embodiment, the case where the present invention is applied as an exhaust device for a cruiser type ship has been described. However, the present invention is applied as an exhaust device for a ship such as a single-seat or two-seater small planing boat equipped with a water jet propulsion device or the like. Of course.

It is the right view which notched a part of starboard side of the cruiser type ship provided with the exhaust apparatus which concerns on embodiment of this invention. It is sectional drawing which looked at the stern vicinity cut | disconnected in the chamber vicinity from the hull back. It is a right view of the ship at the time of middle high speed advance which notched a part of starboard side. It is sectional drawing which looked at the chamber side of the port side cut | disconnected by 1st circular tubular object vicinity from upper direction. It is a right view of a ship at the time of retreat which cut out a part on the starboard side. It is a characteristic view which shows the characteristic of the back pressure of exhaust gas with respect to the rotation speed of an internal combustion engine. It is a characteristic view which shows the characteristic of the exhaust gas noise with respect to the rotation speed of an internal combustion engine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ship 10 Hull 2 Internal combustion engine 3 Exhaust pipe 4 Chamber 41 1st exhaust port 42 2nd exhaust port 43 3rd exhaust port (opening part)
43A Third tubular object (guide member)
43A1 Wall 5 Generator 51 Exhaust pipes H1, H2, H3
Negative pressure space S1 Draft water line S2 Sliding water line S3, S3 ′ Retreating water line S4 Semi-running water line

Claims (5)

A chamber for introducing the exhaust gas of the internal combustion engine through the exhaust pipe is provided on the stern side of the hull,
This chamber contains
A first exhaust opening that opens above the waterline at low speed;
A second exhaust opening that opens below the waterline at low speed;
A wall portion that continues from the opening that opens to the bow side of the second exhaust port toward the inside of the chamber and bypasses the water flow at the water line that moves downward when traveling at high speed from the periphery of the second exhaust port. A guide member that is guided by the wall so as to
The exhaust gas from the first exhaust port is discharged from a low speed including an idling time to a high speed,
The exhaust gas from the second exhaust port is a negative pressure space formed between the second exhaust port and the water flow that is detoured from the periphery of the second exhaust port by the wall portion of the guide member when moving forward at high speed. An exhaust device for a ship characterized by being sucked and discharged. In the ship exhaust device according to claim 1,
The ship exhaust device, wherein the opening of the guide member is also used as a third exhaust port communicating with the inside of the chamber through the wall portion. In the ship exhaust device according to claim 1 or 2,
The stern of the hull stands at an acute angle with respect to the draft line so as to guide the water flow at the draft line that moves downward when retreating and to divert from the surroundings of the first and second exhaust ports, respectively.
The exhaust gas from the first exhaust port is discharged into the air by the water flow diverted from the periphery of the first exhaust port by the stern when retreating,
The exhaust gas from the second exhaust port is sucked and discharged into a negative pressure space formed between the water flow diverted from the periphery of the second exhaust port by the stern and the second exhaust port at the time of retreat. An exhaust device for a ship, characterized in that In the exhaust system for a ship according to any one of claims 1 to 3,
The second exhaust port and the opening of the guide member are respectively provided on the lower surface of the chamber and connected to the lower end of a tubular object protruding upward from the lower surface of the chamber,
The ship exhaust device is characterized in that the wall portion of the guide member is formed by a tubular object connected to the opening. In the exhaust system for a ship according to any one of claims 1 to 4,
A generator is mounted inside the hull,
An exhaust device for a ship, wherein a downstream end of an exhaust pipe of the generator is connected to a chamber.

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