TWI638091B - Expansion chamber diversion structure for micro-turbine generator - Google Patents

Abstract

The present invention provides a micro-turbine generator including a compressor, a flow guide, an expansion chamber and a reheater, the expansion chamber including a gas inlet, a gas outlet and a flow guiding structure, the gas inlet is located One end of the expansion chamber is in communication with the compressor through the flow channel, the gas inlet is for receiving gas compressed by the compressor, the gas outlet is located at the other end of the expansion chamber, and the gas outlet is a reheater is in communication for discharging the gas and flowing the gas into the reheater, the flow guiding structure extending inwardly from an inner wall of the expansion chamber, such that the gas bypasses the gas after passing through the diversion structure The outlet flows into the reheater.

Description

Expansion chamber diversion structure for micro-turbine generator

The present invention discloses a microturbine generator, and more particularly to a microturbine generator having a flow guiding structure.

Micro-turbine generators are devices that use gas turbines to drive generators to generate electricity. They are widely used in aircraft, automobiles and other equipment. Conventional micro-turbine generators usually have compressors, guides, expansion chambers and reheaters, and compressors. Compressing the gas and introducing the compressed gas into the expansion chamber via the flow guiding channel, the expansion chamber reduces the flow rate and uniformity of the compressed gas, and prevents the compressed gas from entering the reheater at an excessively fast flow rate or uneven state, thereby reducing reheating The efficiency of the heat exchange of the device results in poor energy conversion efficiency.

However, conventional expansion chambers for microturbine generators have at least one of the following four problems: First, the length or width of the expansion chamber is too large, since conventional expansion chambers require compressed gas in the expansion chamber. The diffusion angle does not exceed 7 degrees. In order to limit the diffusion angle of the compressed gas, it is necessary to increase the length or width of the expansion chamber, thereby causing a problem of excessive volume. Second, the pressure loss of the compressed gas is too large, and the process of diffusion of the compressed gas in the expansion chamber There must be pressure loss in the middle. If the pressure loss is too large, the heat exchange efficiency of the reheater will be reduced, resulting in poor energy conversion efficiency. Third, the flow rate of the compressed gas is too fast, and fourth, the compressed gas The uniformity is not good.

That is, in the field of expansion chamber design of micro-turbine generators, in order to meet the demand conditions of the applied equipment, at least the volume of the expansion chamber, the pressure loss of the compressed gas, and the flow of the compressed gas must be considered. There are four design requirements, such as the speed and the uniformity of the compressed gas. However, in the process of applying the micro-turbine generator to some equipments, there are still deficiencies and there is room for improvement.

An object of the present invention is to provide a micro-turbine generator having an expansion chamber having a small volume, a small pressure loss of a compressed gas, a flow rate of a compressed gas not too fast, and a high uniformity of a compressed gas, thereby making the micro-turbine generator suitable. Used in many kinds of equipment.

Another object of the present invention is to provide a microturbine generator whose expansion chamber has the advantage of being simple in construction, and thus is easy to manufacture and low in cost.

To achieve the above and other objects, the present invention provides a microturbine generator having a flow guiding structure, the microturbine generator including a compressor, a flow guide, an expansion chamber, and a reheater, the expansion chamber A gas inlet, a gas outlet, and a flow guiding structure are included.

The gas inlet is located at one end of the expansion chamber, and communicates with the compressor through the flow channel, the gas inlet is for receiving gas compressed by the compressor; the gas outlet is located at the other end of the expansion chamber, a gas outlet communicating with the reheater for discharging the gas and flowing the gas into the reheater; the flow guiding structure extending inwardly from an inner wall of the expansion chamber to cause the gas to bypass the flow guiding structure It then flows into the reheater from the gas outlet.

In an embodiment of the microturbine generator of the present invention, the direction of the extension of the center of the gas inlet and the direction of the extension of the center of the gas outlet are at an angle.

In an embodiment of the microturbine generator of the present invention, the direction of the extension of the center of the gas inlet and the direction of the extension of the gas outlet do not overlap.

In an embodiment of the microturbine generator of the present invention, the flow directing structure separates the expansion chamber from a plurality of recirculation zones.

In an embodiment of the microturbine generator of the present invention, the expansion chamber includes a first return wall and a second return wall, the first return wall being connected to one side of the gas inlet and one side of the gas outlet. The second return wall is connected to the other side of the gas inlet and the other side of the gas outlet; and the flow guiding structure is a baffle, and the first return wall and the baffle form a first recirculation zone The second return wall and the baffle form a second recirculation zone, and the gas sequentially flows through the gas inlet, the first recirculation zone, the second recirculation zone, and the gas outlet.

In an embodiment of the micro-turbine generator of the present invention, the baffle has a fixed section and an extended section, and the fixed section is fixed to the inner wall of the first return wall, and the extended section is connected to the fixed section and facing The interior of the expansion chamber extends.

In an embodiment of the microturbine generator of the present invention, one of the wall surfaces of the second return wall is connected to the other side of the gas outlet, and the wall surface is disposed on an extension line of the other side of the gas outlet, and the wall surface The distance from the first return wall is the farthest among the plurality of walls of the second return wall.

In an embodiment of the microturbine generator of the present invention, the gas has a diffusion angle greater than 7 degrees in the second recirculation zone of the expansion chamber.

In an embodiment of the microturbine generator of the present invention, the baffle is a low flow resistance wing profile.

In an embodiment of the microturbine generator of the present invention, the flow rate of the gas flowing through the flow passage is greater than the flow rate of the gas outlet of the expansion chamber into the reheater.

In an embodiment of the microturbine generator of the present invention, the cross-sectional area of the gas inlet is smaller than the cross-sectional area of the gas outlet.

In an embodiment of the micro-turbine generator of the present invention, further comprising a combustion chamber and a turbine, the gas sequentially flowing through the compressor, the flow guiding channel, the expansion chamber, the reheater, the combustion chamber and The turbine, after being compressed and discharged by the compressor, exchanges heat with the gas discharged from the turbine in the reheater.

In an embodiment of the micro-turbine generator of the present invention, a plurality of baffles are further disposed at the gas outlet and the inlet of the reheater.

In an embodiment of the microturbine generator of the present invention, the directions of the baffles are parallel to each other.

In an embodiment of the microturbine generator of the present invention, the direction of the gas inlet is parallel to the direction of the width of the expansion chamber, and the direction of the gas outlet is parallel to the direction of the length of the expansion chamber.

In an embodiment of the microturbine generator of the present invention, the width of the expansion chamber is three times the length of the expansion chamber.

In an embodiment of the microturbine generator of the present invention, the gas inlet of the expansion chamber flow guiding structure has a cross-sectional area of two to five times the cross-sectional area of the flow guiding channel.

Thereby, the expansion chamber of the microturbine generator of the invention has the advantages of small volume, small pressure loss of the compressed gas, low flow rate of the compressed gas, and high uniformity of the compressed gas.

10‧‧‧ gas inlet

11,12‧‧‧ side

20‧‧‧ gas export

21,22‧‧‧ side

30‧‧‧First return wall

31,32,41‧‧‧ wall

40‧‧‧Second return wall

41‧‧‧ wall

50‧‧‧drain structure

51‧‧‧Fixed section

52‧‧‧Extension

60‧‧‧ deflector

100‧‧‧Expansion room

1100‧‧‧ diversion

2000‧‧Reheater

D1‧‧‧Width

D2‧‧‧ length

D3‧‧‧ distance

R1‧‧‧First recirculation zone

R2‧‧‧The second recirculation zone

Θ ₁ , θ ₂ , θ ₃ ‧‧‧ angle

[Fig. 1] is a schematic view showing a first embodiment of an expansion chamber of a microturbine generator of the present invention.

[Fig. 2] is a schematic view showing another embodiment of the flow guiding structure of the microturbine generator of the present invention.

[Fig. 3] is a schematic view showing a second embodiment of the expansion chamber of the microturbine generator of the present invention.

[Figs. 4A to 4C] are views for comparing the gas inlets of the expansion chamber of the present invention with different cross-sectional areas.

[Figs. 5A to 5B] are views for comparing the gas inlets of the expansion chamber of the present invention with different cross-sectional areas.

[Fig. 6A to Fig. 6C] are diagrams for comparing the shapes of the second return walls of the expansion chamber of the present invention.

In order to fully understand the objects, features and advantages of the present invention, the present invention will be described in detail by the following specific embodiments and the accompanying drawings. Referring to Figure 1, there is shown a first schematic view of a first embodiment of a expansion chamber 100 of a microturbine generator of the present invention. The micro-turbine generator includes a compressor, a flow guiding channel 1100, the expansion chamber 100, a reheater 2000, a combustion chamber and a turbine, and the gas flows through the compressor, the guiding channel 1100, and the gas The expansion chamber 100, the reheater 2000, the combustion chamber and the turbine, the gas is compressed and discharged through the compressor, and then heat exchanges with the gas discharged from the turbine in the reheater 2000 to generate electric energy, such as the first As shown, the expansion chamber 100 includes a gas inlet 10, a gas outlet 20, and a flow guiding structure 50 extending from the inner wall of the expansion chamber 100 to allow the gas to bypass the flow. Structure 50 then flows from the gas outlet 20 into the recuperator 2000.

The expansion chamber 100 further includes a first return wall 30 and a second return wall 40. When the gas inlet 10 and the gas outlet 20 are not open, the gas inlet 10, the first return wall 30, and the gas The outlet 20 and the second return wall 40 form a closed expansion chamber. Although the number of return walls is two in the embodiment shown in Fig. 1, the number of return walls of the present invention is not limited to two, but rather, the diverting chamber 100 is separated by the flow guiding structure 50. The number of the return walls may also increase or decrease correspondingly to one or more recirculation zones, and the term "reflow" means a 180 degree change in the direction of the fluid in or along the wall.

The gas inlet 10 is configured to receive the gas compressed by the compressor. In this embodiment, the cross-sectional area of the gas inlet 10 of the expansion chamber 100 is equal to the cross-sectional area of the flow channel 1100, and the gas is in the diversion flow. The flow rate in the passage 1100 is greater than the flow rate at the outlet of the expansion chamber 100 into the reheater 2000.

The gas outlet 20 is for exhausting gas and allowing the gas to flow from the inlet of the reheater 2000. In the present embodiment, the direction of the gas inlet 10 is offset from the direction of the gas outlet 20, that is, the gas inlet 10 Not facing the gas outlet 20, the compressed gas does not directly rush into the gas outlet 20 from the gas inlet 10, the direction of the gas inlet 10 being approximately parallel to the width W of the expansion chamber, the direction of the gas outlet 20 being approximately parallel In the direction of the length L of the expansion chamber, the cross-sectional area of the gas inlet 10 is smaller than the cross-sectional area of the gas outlet 20.

In other possible embodiments, the direction in which the direction of the gas inlet 10 is offset from the direction of the gas outlet 20 further includes: (1) an extension line direction of the center of the gas inlet 10 and an extension line direction of the center of the gas outlet 20 At an angle, the angle is about 90 degrees in this embodiment, but may be other angles, such as 60 degrees in other possible embodiments; (2) the direction of the extension of the center of the gas inlet 10 and the center of the gas outlet 20 The direction of the extension lines does not overlap.

The first return wall 30 is connected to one side 11 of the gas inlet 10 and one side 21 of the gas outlet 20, and the second return wall 40 is connected to the other side 12 of the gas inlet 10 and the gas outlet 20 One side 22, although FIG. 1 provides a preferred aspect of the shape and position of the first return wall 30 and the second return wall 40, the first return wall 30 and the second return wall 40 The shape is not limited to this.

The first returning wall 30 and the flow guiding structure 50 form a first recirculation zone R1. The second recirculation wall 40 and the flow guiding structure 50 form a second recirculation zone R2, and the gas flows through the gas inlet 10 in sequence. The first recirculation zone R1, the second recirculation zone R2 and the gas outlet 20, the flow guiding structure 50 can be a baffle.

Although FIG. 1 provides a preferred aspect of the shape, position, and number of the flow guiding structure 50, the shape, position, and number of the flow guiding structure 50 are not limited thereto. For example, the guiding structure The baffle 50 may be a curved baffle having one or more bends. For example, the baffle 50 may be disposed on an inner wall surface of the second return wall 40 and extend toward the inside of the expansion chamber 100. In addition, the implementation of the flow guiding structure 50 is not limited to the baffle, and may also be a non-sheet structure. If the guiding structure 50 includes a baffle, the number of the baffles may be one or more. One.

In the present embodiment, the direction of the gas inlet 10 is not only shifted from the direction of the gas outlet 20 but is even close to vertical, so that the compressed gas does not directly rush into the gas outlet 20 from the gas inlet 10, and further, due to the gas inlet The cross-sectional area of 10 is much smaller than the cross-sectional area of the gas outlet 20. According to the law of conservation of mass, the gas flow rate will be slowed down from the small cross-sectional area to the large cross-sectional area, so this embodiment is advantageous for slowing down the compressed gas. The flow rate further, in this embodiment, the recirculation zone is generated inside the expansion chamber 100 by the flow guiding structure 50, which can further reduce the flow rate of the compressed gas and increase the uniformity of the compressed gas.

In this embodiment, the recirculation zone R1, R2 is generated inside the expansion chamber 100 by the flow guiding structure 50, so that the compressed gas can be sequentially expanded in the interior of the expansion chamber 100 according to the flow guiding direction to gradually reduce the flow velocity and improve the uniformity. The pressure loss is not greatly increased, and the volume of the expansion chamber 100 does not need to be increased. Further, the expansion chamber 100 of the present embodiment has a simple structure and is easy to manufacture and low in cost.

The outer shape of the expansion chamber 100, the position and angle of the flow guiding structure, and the width of the gas inlet 10 of the present embodiment as shown in Fig. 1 are particularly designed, so that the above-described effects can be particularly remarkable. However, it is understood by those of ordinary skill in the art that the shape of the expansion chamber, the position and angle of the flow guiding structure, the width of the gas inlet, and the like are all adjustable, and the general knowledge in the technical field to which the present invention pertains. Even if the size of the expansion chamber and the position of the diversion structure are adjusted according to the demand or deliberately The angle, the width of the gas inlet, may not be deviated from the scope of the invention as intended, and the scope of the invention is not limited to the embodiment shown in Fig. 1.

If the flow guiding structure 50 is a baffle, the baffle may have a fixed section 51 and an extended section 52. The fixed section 51 is fixed to the inner wall of the first returning wall 30, and the extending section 52 is connected to The fixing section 51 extends toward the inside of the expansion chamber 100. The fixing section 51 of the deflector is parallel to one of the wall surfaces 31 of the first returning wall 30, and the extension 52 of the deflector and the extension of the wall 31 The angle θ _{1 of the} line is preferably between 30 and 60 degrees, the gas outlet 20 is located on the extension of the wall 31, and further, if the width D1 of the gas outlet 20 is X, the extension 52 of the deflector The length D2 is preferably between 0.35X and 0.55X, and the baffle has a turning point 53 between the fixing section 51 and the extending section 52, and the distance between the turning point 53 and one side 21 of the gas outlet 20 D3 is preferably between 0.2X and 0.3X.

In addition, the other wall surface 32 of the first return wall 30 is preferably a slope, and the angle θ ₂ between the wall surface 32 and the extension line of the side 11 of the gas inlet 10 connected thereto is between 0 and 90 degrees. Excluding 0 degrees and 90 degrees, the angle θ ₃ between the direction of the gas inlet 10 and the length L direction of the expansion chamber 100 is between 0 degrees and 90 degrees. If the two angles θ ₂ and θ _{3 are the} same, then The direction of the gas inlet 10 will be parallel to the wall 32.

Furthermore, if the angle θ ₃ is 0 degrees such that the direction of the gas inlet 10 is parallel to the direction of the gas outlet 20 , the deflector may be disposed in an extension line of the gas inlet 10 and the gas outlet 20 . Between the extension lines of the direction, the gas is prevented from rushing directly into the gas outlet 20 from the gas inlet 10 in a straight line.

In another embodiment, the gas outlet 20 has an area of 14,451 mm ² and the reheater inlet area is 970,16 mm ² , which is 6.7 times the area of the gas outlet 20 . Therefore, according to the law of conservation of mass, the flow rate of the outlet is decreased by 6.7 times. When the flow rate of compressed gas is 37m/s, the pressure loss of the expansion chamber is 0.11%, and the diffusion angle is 4.29 degrees. Under the same conditions, the traditional expansion chamber needs 671mm, but the expansion chamber of this case is only 146mm, so the expansion of this case The volume of the chamber is significantly smaller.

In addition, if the design of the baffle is not used, only the airflow with the same flow path area of the compressor will enter the reheater, so 85% of them are the heat transfer area conversion, taking the total pressure loss of the reheater 2.5% as an example. The heat exchange efficiency will be reduced from 88% to 46.8%, and therefore, the deflector 50 of the present invention has remarkable effects.

As shown in FIG. 2, the shape of the baffle can be a low flow resistance wing shape. This embodiment can reduce the wind resistance by designing the baffle to be streamlined, thereby reducing the pressure during the return flow of the compressed gas. damage.

Next, please refer to FIG. 3, which is a schematic view of a second embodiment of the microturbine generator of the present invention. The element of the second embodiment of the micro-turbine generator is substantially the same as the micro-turbine generator shown in FIG. 1 , wherein the micro-turbine generator of the second embodiment further includes a plurality of baffles 60 disposed at the gas outlet 20 . And the inlet of the reheater 2000, the baffles 60 may be parallel to each other to uniformly direct the gas flowing to the gas outlet 20 to the reheater 2000, avoiding gas being directly along the triangular region The path moves, affecting uniformity and causing pressure loss.

In addition, it should be noted that the inlet of the reheater 2000 of the present embodiment is merely an example. In other possible embodiments, the inlet of the reheater 2000 may be a shape other than a triangle, such as a rectangle or a ladder. That is, the type of the reheater to which the present invention is applied and the shape of the inlet thereof are not limited thereto.

Referring to FIGS. 4A to 4C, in FIG. 4A, the wall surface 32 is not a slope, and the cross-sectional area of the gas inlet 20 of the expansion chamber 100 is equal to the cross-sectional area of the guide channel 1100. For comparison, in FIG. 4B The cross-sectional area of the gas inlet 20 of the expansion chamber 100 is twice the cross-sectional area of the flow channel 1100. In FIG. 4C, the cross-sectional area of the gas inlet 20 of the expansion chamber 100 is the flow path 1100. Four times the cross-sectional area.

Comparing FIGS. 4A to 4C, it can be found that the uniformity of FIG. 4B is optimal, and therefore, when the cross-sectional area of the gas inlet 20 of the expansion chamber 100 is designed to be two to five times the cross-sectional area of the flow guide 1100. The compressed gas has a better uniformity, and at about twice, the compressed gas has an optimum uniformity.

Referring to FIGS. 5A to 5B, in FIG. 5A, the wall surface 32 is a sloped surface, and the cross-sectional area of the gas inlet 20 of the expansion chamber 100 is equal to the cross-sectional area of the flow guiding channel 1100. For comparison, in FIG. 5B The gas inlet 20 of the expansion chamber 100 has a cross-sectional area that is three times the cross-sectional area of the flow channel 1100.

Comparing FIGS. 5A to 5B, it can be found that the uniformity of FIG. 5B is better. Therefore, when the cross-sectional area of the gas inlet 20 of the expansion chamber 100 is designed to be approximately three times the cross-sectional area of the guide channel 1100, The compressed gas has the best uniformity.

Referring to FIGS. 6A-6C, the wall surface 32 is a sloped surface. In FIG. 6C, one of the wall surfaces 41 of the second return wall 40 is connected to the other side 22 of the gas outlet 20. The wall surface 41 is disposed on the wall surface 41. An extension line of the other side 22 of the gas outlet 20, and the distance between the wall surface 41 and the first return wall 30 is the farthest among the plurality of walls of the second return wall 40.

Comparing FIGS. 6A to 6C, it can be found that the uniformity of FIGS. 6A to 6C is the same, but the volume of the expansion chamber of FIG. 6C is the smallest, and therefore, the second return wall 40 is shortened to the sixth FIG. optimal.

In summary, the expansion chamber of the microturbine generator of the present invention has the advantages of small volume, small pressure loss of compressed gas, low flow rate of compressed gas, and high uniformity of compressed gas.

The invention has been described above in terms of the preferred embodiments, and it should be understood by those skilled in the art that the present invention is not intended to limit the scope of the invention. Should pay attention Variations and permutations equivalent to the embodiments are intended to be within the scope of the invention. Therefore, the scope of protection of the present invention is defined by the scope of the patent application.

Claims (8)

A micro-turbine generator having a flow guiding structure, the micro-turbine generator comprising a compressor, a flow guiding channel, an expansion chamber and a reheater, the expansion chamber comprising: a gas inlet located at one end of the expansion chamber The gas inlet is configured to receive the gas compressed by the compressor through the flow channel; a gas outlet is located at the other end of the expansion chamber, and the gas outlet is in communication with the reheater For discharging the gas and flowing the gas into the reheater; and a flow guiding structure extending inwardly from the inner wall of the expansion chamber, separating the expansion chamber from the plurality of recirculation zones, and bypassing the gas The flow guiding structure flows from the gas outlet into the reheater; wherein the expansion chamber includes a first return wall and a second return wall, the first return wall is connected to one side of the gas inlet and the gas outlet The second returning wall is connected to the other side of the gas inlet and the other side of the gas outlet; and the flow guiding structure is a baffle, and the first returning wall and the baffle form a First recirculation zone, the second return wall The baffle forming a second recirculation zone, the gas sequentially flows through the gas inlet, the first recirculation zone, the recirculation zone and the second gas outlet. The microturbine generator of claim 1, wherein an extension line direction of the gas inlet center and an extension line direction of the gas outlet center have an angle. The microturbine generator of claim 1, wherein an extension line direction of the gas inlet center and an extension line direction of the gas outlet do not overlap. The micro-turbine generator of claim 1, wherein the baffle has a fixed section and an extension, the fixed section being fixed to an inner wall of the first return wall, the extension being connected to the fixed section and facing The interior of the expansion chamber extends. The micro-turbine generator of claim 1, wherein one of the wall surfaces of the second return wall is connected to the other side of the gas outlet, the wall surface is disposed on an extension line of the other side of the gas outlet, and The distance between the wall and the first return wall is the farthest among the plurality of walls of the second return wall. The microturbine generator of claim 1, wherein the gas has a diffusion angle greater than 7 degrees in the second recirculation zone of the expansion chamber. The micro-turbine generator of claim 1, wherein the baffle is a low flow resistance wing shape, wherein a flow rate of the gas flowing in the flow channel is greater than a gas outlet in the expansion chamber flows into the reheater The flow rate, wherein the cross-sectional area of the gas inlet is smaller than the cross-sectional area of the gas outlet. The micro-turbine generator of claim 1, further comprising a combustion chamber and a turbine, the gas sequentially flowing through the compressor, the flow channel, the expansion chamber, the reheater, the combustion chamber, and the The turbine, after being compressed and discharged by the compressor, exchanges heat with the gas discharged from the turbine in the reheater.