JPS5812479B2 - Yobisenkaitabochayasouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to turbocharging technology, and more particularly to an apparatus for imparting pre-swirl to air entering a compressor.

Turbochargers are widely used in internal combustion engines, especially large diesel engines for trucks.

Compared to superchargers, which draw power directly from the engine's crankshaft, turbochargers are powered by the engine's exhaust gases.

Exhaust gas is coupled to a turbine, and the turbine is coupled to a compressor.

Ambient air is compressed by a compressor and supplied to the engine inlet.

Pre-swirling devices for air compressors are known.

Such devices often include a plurality of slanted vanes extending across the inlet of the compressor, thereby imparting an air swirl component to the incoming air to reduce the amount of work at a given compressor speed.

Such devices are shown, for example, in Taylor, US Pat. No. 2,637,486 and Muhlberg, US Pat. No. 2,690,293.

Pre-swirling the air against the impeller increases the amount of work done by the compressor, while swirling the air in the same direction reduces the amount of work done by the compressor.

The effect of pre-turning is described in Anderson and Shouman, published in March 1963.
man) co-author, Journal of the American Society of Mechanical Engineers (ASMEPap)
er)'' No. 63-AHGH-55.

As described in Anderson et al., varying the amount of pre-swirl at a constant compressor speed is equivalent to varying the compressor speed without pre-swirl.

Additionally, the pre-swivel moves the surge line (stall line) to a lower flow rate, thus increasing the operating range.

It is often desirable to vary the amount of pre-swirled air entering the compressor, and for this purpose such vanes have been provided with linkages that simultaneously vary the vane angle.

Although such structures accomplish the desired purpose, they are relatively expensive because several moving parts are required.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pre-swirling turbocharger device which overcomes the drawbacks of prior art devices and is simple in construction and inexpensive to manufacture.

An arrangement of the present invention provides a pre-swirl turbocharger apparatus for imparting pre-swirl to air entering the compressor, including a compressor having an impeller and an elongated duct defining an interior communicating with an inlet portion to the impeller; The duct has a butterfly valve disposed within the duct to control the amount of air passing through the duct to the impeller, the duct having a butterfly valve disposed within the duct to provide communication between the interior and exterior plenum chambers of the duct. a plurality of air inlet passages, the air inlet passages being axially disposed within the duct between the butterfly valve and the impeller and imparting a tangential velocity to air entering the air inlet passage from the plenum chamber; and a second duct surrounding the duct, wherein one end of the second duct is connected to the duct in a region downstream of the air inlet passageway to form a plenum chamber closed at one end. , and the other end of the filling chamber is open and communicates with the atmosphere.

The previously described configuration of the invention utilizes a plurality of vanes located around the inlet of the compressor.

A butterfly valve is provided in the duct leading to the compressor.

By adjusting the angular position of the butterfly valve, the amount of air passing through the vanes and entering the compressor is varied, thereby varying the amount of air pre-swirl.

Instead of a conventional structure in which several valves must be adjusted simultaneously to vary the amount of pre-swirling of air entering the compressor, in the configuration of the present invention only one valve is used. used.

This structure also moves the surge line, increasing the operating range.

Referring to the drawings, numeral 10 indicates a conventional turbocharger compressor cover.

The elements indicated by the numeral 11 in dotted lines represent conventional impellers.

The compressor cover has an annular chamber 12 for receiving compressed air, defined by a hollow torus 14, having an integrally formed inlet portion 18 around which an annular flange 20 is provided. .

The numeral 22 designates an annulus provided with a plurality of diagonal vanes 24.

A duct 28 is fixed to the left side surface of the annulus 22, for example by welding.

Vane 24 is welded or integrally cast to the right side surface of the annulus.

An annular flange 20 is fixed to the right edge of the vane 24 by, for example, welding.

It should be noted that the annular body 22 and the annular flange 20 are located on an extension of the duct 28, and therefore are considered to form a part of the duct 28.

The interior 30 of the duct 28 is provided with a conventional butterfly valve, the disc 34 of which is attached to a rotatable shaft 36.
This shaft 36i lever assembly 3
8.40 can be adjusted to any desired angular position.

The inlet end of duct 28 is coupled to an air filter 42 that is radially flared to be secured within the inlet of second duct 440 .

The interior of this second duct 44 defines a plenum 46 which communicates with the compressor inlet section 18 via the vanes 24.

Vane 240 radially outermost portion and annular flange 20
The axial space between the ring body 22 and the annular body 22 forms a circumferential air inlet passage 25 (see FIG. 3) through which air passes.

These air inlet channels taper towards the outlet area 26 as nozzles.

The operation of the device is as follows.

The butterfly valve disk 34 is angularly positioned to provide the desired airflow into the interior 30 of the duct 28, and the suction pressure in the inlet section 18 resulting from the discharge action of the rotation of the impeller directs ambient air to the air filter. 42, enters duct 28 and is discharged through a compressor.

A predetermined amount of air also enters the compressor through air inlet passage 25.

If the operating condition is such that a prewhirl is desired to change to a surge condition, the butterfly valve disc 34 is closed somewhat to limit the amount of air flowing through the duct 28.

Also, a quantity of air is drawn in through the air filter 42 , through the plenum chamber 46 and through the air inlet passage 25 .

As clearly shown in FIG. 3, the air is given a tangential velocity in the same direction as the direction of rotation of the impeller.

Other air enters the compressor inlet section 18 through the interior 30, as previously described.

If a larger proportion of pre-swirled air is desired, the butterfly valve is rotated further to inhibit the passage of air through the duct 28, thus increasing the amount of air flowing through the air inlet passage 25 and outlet area 26. and is pre-swiveled before entering the inlet section 18.

Instead of such vanes, other arrangements providing angled nozzles, such as holes drilled or cast in a thick ring, may be used.

Referring to FIG. 4, the butterfly disc 34 is connected to the duct 2.
The operation of the device is shown at 49 degrees to the flow axis at 8.

Effect curves for the indicated compressor speed are shown with the left portion of the curves joining the surge line.

Operating conditions are unstable to the left of the surge line, so all compressor operation must be to the right of this curve.

Figure 5 shows that the butterfly valve is fully open.
FIG. 4 is a view similar to FIG. 4, so that a minimum of pre-swirl is imparted to the air entering the inlet section 18 of the compressor.

As is clear from a comparison of FIGS. 4 and 5, the effect of a positive pre-swivel is to move the surge line to the left, as is well known to those skilled in the art, thereby increasing the operating range of the device.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a pre-swing turbocharger device of the present invention. FIG. 2 is a cross-sectional view of the inclined vane and the ring supporting it. FIG. 3 is a plan view of the vane and annulus of FIG. 2; Figure 4 shows 1.02 with the butterfly valve open 49 degrees.
2 is a graph illustrating the operation of a device with a nozzle gap of Cm (0.4 inch). FIG. 5 is a graph similar to FIG. 4 when the butterfly valve is fully open. DESCRIPTION OF SYMBOLS 10... Compressor cover, 11...-impeller, 12... Annular chamber, 14... Torus, 18... Inlet part, 20... Annular flange, 24... Vane, 28... Duct, 34... …
Disc, 36...Shaft, 38, 40...Lever assembly, 42...Air filter, 44...Second duct, 25...
...air inlet passage, 26...exit area.

Claims (1)

[Claims] 1. A pre-swirl turbocharger apparatus for imparting a pre-swirl to air entering the compressor, comprising a compressor having an impeller 11 and an elongated duct 28 forming an interior 30 communicating with an inlet portion to the impeller 11, wherein the The duct 28 has a butterfly valve disposed within the duct to control the amount of air passing through the duct 28 to the impeller 11, providing communication between the interior 30 and the exterior plenum 46 of the duct 28. including a plurality of air inlet passages 25 disposed within said duct 28, wherein said air inlet passages 25
is located axially within the duct 28 between the butterfly valve and the impeller 110 and is inclined to impart a tangential velocity to the air entering the air inlet passage 25 from the plenum 46 and surrounds the duct. a second duct 44, wherein one end of the second duct is connected to the duct 2B in the region downstream of the air inlet passage 25 to form a plenum chamber 46 closed at one end; 46
A pre-swivel turbocharger device characterized in that the other end is open and communicates with the atmosphere.