CN210152728U

CN210152728U - Automobile-used waste heat recovery system and vortex expander thereof

Info

Publication number: CN210152728U
Application number: CN201920576178.9U
Authority: CN
Inventors: 刘祯
Original assignee: Hubei University of Arts and Science
Current assignee: Hubei Kangjirun Dynamo Electric Technology Co ltd
Priority date: 2019-04-25
Filing date: 2019-04-25
Publication date: 2020-03-17
Anticipated expiration: 2029-04-25

Abstract

The utility model discloses an automobile-used waste heat recovery system and vortex expander thereof of expander technical field aims at solving among the prior art vortex expander exhaust resistance big, and mechanical energy consumption scatters the increase, the technical problem of expander inefficiency. A kind of vortex expander, including the body, there are air collecting chambers communicated with intake duct and working chambers communicated with exhaust duct in the said body, the gas entering the air collecting chamber from the intake duct can flow into the working chamber and discharge through the exhaust duct; the exhaust passage comprises a first exhaust passage and a second exhaust passage, and the first exhaust passage and the second exhaust passage are centrosymmetric about a central point of the working cavity. The utility model provides a pair of automobile-used waste heat recovery system and expander thereof have improved the exhaust process of vortex expander, have reduced the exhaust pressure of vortex expander, and the mechanical energy dissipation reduces, and expander efficiency has obtained the promotion.

Description

Automobile-used waste heat recovery system and vortex expander thereof

Technical Field

The utility model belongs to the technical field of the expander, concretely relates to automobile-used waste heat recovery system and vortex expander thereof.

Background

Compared with other types of volumetric expanders, the scroll expander has the outstanding advantages of stable operation, low noise, high efficiency, compact structure, good reliability and the like and the requirement of operating conditions of small flow and high expansion ratio, and becomes a better acting part in an organic Rankine cycle waste heat recovery system of the vehicle engine. Although the technical application of the scroll machine as a compressor in the refrigeration field is mature, the application research of the scroll expander is still deficient, and no mature product exists, and most scroll expanders are formed by modifying the scroll compressor. In the actual working process, even if the well-designed scroll compressor is modified into an expander, the actual working process of the scroll expander has a larger difference compared with the theoretical process due to the influence of factors such as friction, leakage, internal flow loss, heat transfer and the like. The great part of the flow loss of the scroll expander is that the asymmetric degree of the flow field distribution of the back pressure cavity and the exhaust cavity at two sides is high due to the eccentric rotation of the movable scroll plate, so that the pulsation of the exhaust airflow and the secondary flow loss in the back pressure cavity are caused.

The existing scroll expander is influenced by the arrangement position of a single-side geometric exhaust hole and the eccentric rotation of a movable scroll wrap, the non-uniform degree of pressure distribution in an opposite side exhaust cavity and a back pressure cavity is high, particularly the asymmetric distribution in the back pressure cavities at two sides deteriorates the exhaust process of the expander, the mechanical energy consumption is increased due to large exhaust resistance, and the efficiency of the expander is reduced.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an automobile-used waste heat recovery system and vortex expander thereof to it is big to solve among the prior art vortex expander exhaust resistance, and mechanical energy consumption scatters the increase, the technical problem of expander inefficiency.

In order to achieve the above purpose, the utility model adopts the technical proposal that: a kind of vortex expander, including the body 1, there are collection chambers 61 communicated with inlet 6 and working chambers 2 communicated with exhaust passage in the said body 1, the gas entering collection chamber 61 from inlet 6 can flow into working chamber 2 and discharge through the exhaust passage; the exhaust passage includes a first exhaust passage 51 and a second exhaust passage 52, and the first exhaust passage 51 and the second exhaust passage 52 are symmetrical about a center point of the working chamber 2.

The central axis of the first exhaust passage 51 and the central axis of the second exhaust passage 52 are both perpendicular to the central axis of the intake passage 6.

The movable vortex teeth 3 and the fixed vortex teeth 4 with the same spiral direction are arranged in the working cavity (2), and gas entering the working cavity 2 is discharged from the exhaust passage along with the eccentric rotation of the movable vortex teeth 3.

The air inlet 6 is connected with the air collection chamber 61 along the tangential direction of the shell of the air collection chamber 61, air enters from the air inlet 6 along the tangential direction of the air collection chamber 61, and air flow which does circular motion is formed in the air collection chamber 61.

A channel connected with the air inlet of the working cavity 2 is arranged in the center of the air collection chamber 61, and the air in the air collection chamber 61 enters the working cavity 2 through the channel.

A vehicle waste heat recovery system is characterized in that a first exhaust passage and a second exhaust passage of a vortex expander are connected with an exhaust pipeline through a tee joint, and the exhaust pipeline is sequentially connected with a cooler 71, a liquid storage tank 72, a mechanical diaphragm pump 73 and an evaporator 75; the air inlet channel of the scroll expander is communicated with the steam outlet of the evaporator 75, the evaporator 75 absorbs the waste heat of the automobile exhaust, and high-temperature steam is generated to drive the scroll expander to do work and drive the generator 76 to generate electricity.

A pressure buffer 74 is provided on a discharge line of the mechanical diaphragm pump 73.

The system further comprises a bypass pipeline, one end of the bypass pipeline is communicated with a steam outlet of the evaporator 75, the other end of the bypass pipeline is communicated with the cooler 71, and a fifth switching valve 703 is arranged on the bypass pipeline; a sixth switching valve 701 is connected to an air inlet channel of the scroll expander, and a fourth switching valve 702 is connected to an exhaust pipeline; when the scroll expander is in the operating state, the sixth switching valve 701 and the fourth switching valve 702 are kept open, and the fifth switching valve 703 is closed, and when the scroll expander is in the non-operating state, the sixth switching valve 701 and the fourth switching valve 702 are kept closed, and the fifth switching valve 703 is opened.

Compared with the prior art, the utility model discloses the beneficial effect who reaches: the utility model provides a pair of automobile-used waste heat recovery system and expander thereof have improved the exhaust process of vortex expander, have reduced the exhaust pressure of vortex expander, and the mechanical energy dissipation reduces, and expander efficiency has obtained the promotion.

Drawings

FIG. 1 is a schematic perspective view of a prior art single-sided exhaust scroll expander;

fig. 2 is a schematic plan view of a waste heat recovery system for a vehicle and an opposite-side exhaust vortex expander thereof according to an embodiment of the present invention;

fig. 3 is a schematic view illustrating a vehicle waste heat recovery process of a vehicle waste heat recovery system and an expansion machine thereof according to an embodiment of the present invention;

FIG. 4 is a three-dimensional simulation diagram of the flow field distribution in the exhaust cavity and the back pressure cavity of the single-side exhaust scroll expander;

FIG. 5 is a three-dimensional simulation diagram of the flow field distribution in the exhaust cavity and the back pressure cavity of the opposite-side exhaust vortex expander;

in the figure: 1. a housing; 2. a working chamber; 3. a movable scroll wrap; 4. a fixed wrap; 5. an original exhaust passage; 51. a first exhaust duct; 52. a second exhaust passage; 6. an air inlet channel; 61. a gas collection chamber; 71. a cooler; 72. a liquid storage tank; 73. a mechanical diaphragm pump; 74. a pressure buffer; 75. an evaporator; 76. a generator; 77. a lamp load; 701. a sixth switching valve; 702. a fourth switching valve; 703. and a fifth switching valve.

Detailed Description

The present invention will be further described with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

It should be noted that, in the description of the present invention, the terms "front", "rear", "left", "right", "upper", "lower", "inner", "outer", etc. indicate the directions or positional relationships based on the directions or positional relationships shown in the drawings, and are only for convenience of description of the present invention but do not require the present invention to be constructed and operated in a specific direction, and thus, should not be construed as limiting the present invention. As used in the description of the present invention, the terms "front," "back," "left," "right," "up," "down" and "in" refer to directions in the drawings, and the terms "inner" and "outer" refer to directions toward and away from, respectively, the geometric center of a particular component.

As shown in FIG. 1, the central axes of the inlet and outlet channels of the prior art scroll expander are in the same plane. High-temperature working medium enters the gas collection chamber 61 along the tangential direction of the gas collection chamber 61 through the gas inlet channel 6, gas circularly moves in the gas collection chamber 61 and enters the working cavity 2, and the gas is discharged through the gas discharge channel arranged on one side along with the eccentric rotation of the movable vortex tooth. As shown in fig. 4, a three-dimensional simulation diagram of flow field distribution in the exhaust cavity and the back pressure cavity of the unilaterally-exhausted scroll expander is shown, when the rotation angle of the main shaft is 0 °, the flow of the back pressure cavities at two sides of the unilaterally-exhausted scroll expander presents obvious asymmetry, and particularly, a plurality of secondary flow and return flow vortexes are formed in a channel between the outer wall surface of the tail end of the movable scroll tooth and the wall surface of the shell, and the exhaust flow resistance is greatly increased by the loss of the secondary flow. The existing scroll expander is influenced by the arrangement position of a single-side geometric exhaust hole and the eccentric rotation of a movable scroll wrap, the non-uniform degree of pressure distribution in an exhaust cavity and a back pressure cavity is high, particularly the non-symmetrical distribution in the back pressure cavities at two sides deteriorates the exhaust process of the expander, the mechanical energy consumption is increased due to larger exhaust resistance, and the efficiency of the expander is reduced.

As shown in fig. 2, the embodiment of the present invention provides a schematic plan view of a scroll expander of an opposite exhaust structure, a central axis of an original exhaust passage 5 rotates 90 ° counterclockwise around an O' point to obtain a first exhaust passage 51, and a second exhaust passage 52 is obtained by making central symmetry of the first exhaust passage 51 along a central point of a working chamber 2. As shown in fig. 1 and 2, the high-temperature working medium enters the gas collection chamber 61 through the gas inlet channel 6 along the tangential direction of the gas collection chamber 61, and the gas circularly moves in the gas collection chamber 61 and enters the working chamber 2 through a channel between the center of the gas collection chamber and the gas inlet of the working chamber 2. The movable spiral wrap 3 and the fixed spiral wrap 4 with the same spiral direction are arranged in the working cavity 2, and gas entering the working cavity 2 is discharged from the first gas discharge passage 51 and the second gas discharge passage 52 along with the eccentric rotation of the movable spiral wrap 3. As shown in fig. 5, the three-dimensional simulation diagram of the distribution of the flow fields in the exhaust cavity and the back pressure cavity of the opposite-side exhaust scroll expander is shown, when the rotation angle of the main shaft is 0 °, the flow in the exhaust process of the opposite-side exhaust scroll expander is more uniform, and no obvious secondary flow exists in the back pressure cavity. The embodiment of the utility model provides a contralateral exhaust vortex expander has improved the exhaust process of vortex expander, has reduced the exhaust pressure of vortex expander, and machinery can dissipate the reduction, and expander efficiency has obtained the promotion.

As shown in fig. 3, for the embodiment of the present invention provides a waste heat recovery flow diagram for a vehicle and an expansion machine thereof, a first exhaust passage 51 and a second exhaust passage 52 of a scroll expansion machine are connected to a system pipeline after being converted into an exhaust passage through a tee joint, a cooler 71, a liquid storage tank 72, a mechanical diaphragm pump 73, a pressure buffer 74 and an evaporator 75 are sequentially connected to the exhaust passage pipeline of the scroll expansion machine, the scroll expansion machine drives a generator 76 to generate electricity, and a power supply lamp load 77 is used. The embodiment of the utility model is also provided with a bypass pipeline, one end of the bypass pipeline is communicated with the steam outlet of the evaporator 75, the other end is communicated with the cooler 71, and the bypass pipeline is provided with a fifth switching valve 703; a sixth switching valve 701 is connected to an air inlet channel of the scroll expander, and a fourth switching valve 702 is connected to an exhaust pipeline; when the scroll expander is in a working state, the sixth switching valve 701 and the fourth switching valve 702 are kept open, the fifth switching valve 703 is closed, gas enters the scroll expander through the sixth switching valve 701, and after the scroll expander applies work, the gas enters the cooler 71 through the fourth switching valve 702; when the scroll expander is in a non-operating state, the sixth switching valve 701 and the fourth switching valve 702 are kept closed, the fifth switching valve 703 is opened, and at this time, the gas flowing out of the evaporator directly enters the cooler 71 through the fifth switching valve 703 on the bypass line. The cooler 71 is used for cooling gas discharged by the vortex expansion machine, the cooled gas is liquefied into liquid and enters the liquid storage tank 72, and an exhaust valve is arranged on the liquid storage tank 72 to discharge redundant gas; the mechanical diaphragm pump 73 sends the liquid in the liquid storage tank 72 to the evaporator 75 for absorbing redundant heat from the automobile exhaust, and the liquid enters the vortex expander after absorbing heat and gasifying to push the movable vortex teeth of the vortex expander to do work. A Y-filter is provided at the inlet of the mechanical diaphragm pump 73 to protect the mechanical diaphragm pump 73; a turbine flow meter and a Y-filter protecting the turbine flow meter are also provided on the line between the mechanical diaphragm pump 73 and the evaporator 75 to monitor the system fluid flow. A pressure buffer 74 is provided on the outlet line of the mechanical diaphragm pump 73 to stabilize the system pressure and reduce system pressure fluctuations. The stable system pressure can make the flow in the exhaust process of the scroll expander more uniform, improve the exhaust process of the scroll expander, reduce the dissipation of mechanical energy and improve the efficiency of the expander.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be considered as the protection scope of the present invention.

Claims

1. A vortex expander is characterized by comprising a shell (1), wherein a gas collection chamber (61) communicated with a gas inlet channel (6) and a working cavity (2) communicated with a gas outlet channel are arranged in the shell (1), and gas entering the gas collection chamber (61) from the gas inlet channel (6) can flow into the working cavity (2) and be exhausted through the gas outlet channel; the exhaust passage comprises a first exhaust passage (51) and a second exhaust passage (52), and the first exhaust passage (51) and the second exhaust passage (52) are symmetrical with respect to the center point of the working cavity (2).

2. The scroll expander according to claim 1, wherein the central axis of the first exhaust passage (51) and the central axis of the second exhaust passage (52) are perpendicular to the central axis of the intake passage (6).

3. A scroll expander according to claim 1, wherein the movable scroll wrap (3) and the fixed scroll wrap (4) having the same spiral direction are provided in said working chamber (2), and gas introduced into the working chamber (2) is discharged from the discharge passage by eccentric rotation of the movable scroll wrap (3).

4. The scroll expander according to claim 1, wherein the inlet channel (6) is connected with the plenum chamber (61) along a tangential direction of a housing of the plenum chamber (61), and the gas enters from the inlet channel (6) along the tangential direction of the plenum chamber (61) to form a circular flow in the plenum chamber (61).

5. Scroll expander according to claim 1, characterized in that the collection chamber (61) is centrally provided with a passage connected to the inlet of the working chamber (2), through which passage the gas in the collection chamber (61) enters the working chamber (2).

6. A waste heat recovery system for a vehicle, which is characterized by comprising the scroll expander as claimed in any one of claims 1 to 5, wherein a first exhaust passage and a second exhaust passage of the scroll expander are connected with an exhaust pipeline through a tee joint, and the exhaust pipeline is sequentially connected with a cooler (71), a liquid storage tank (72), a mechanical diaphragm pump (73) and an evaporator (75); the air inlet channel of the vortex expander is communicated with a steam outlet of the evaporator (75), the evaporator (75) absorbs waste heat of automobile exhaust, high-temperature steam is generated to drive the vortex expander to do work, and the generator (76) is driven to generate electricity.

7. The vehicle waste heat recovery system according to claim 6, wherein a pressure buffer (74) is provided on a discharge line of the mechanical diaphragm pump (73).

8. The vehicle waste heat recovery system according to claim 6, further comprising a bypass pipeline, wherein one end of the bypass pipeline is communicated with a steam outlet of the evaporator (75), the other end of the bypass pipeline is communicated with the cooler (71), and a fifth switching valve (703) is arranged on the bypass pipeline;

a sixth switching valve (701) is connected to an air inlet channel of the scroll expander, and a fourth switching valve (702) is connected to the exhaust pipeline;

when the scroll expander is in an operating state, the sixth switching valve (701) and the fourth switching valve (702) are kept open, and the fifth switching valve (703) is closed, and when the scroll expander is in a non-operating state, the sixth switching valve (701) and the fourth switching valve (702) are kept closed, and the fifth switching valve (703) is kept open.