JP2006176042A - Waste heat recovery device and heat exchanger therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waste heat recovery device for a vehicle having immediate heating performance and capable of effectively utilizing exhaust heat throughout the year and a heat exchanger for heating the inside of a cabin for realizing the device. <P>SOLUTION: The waste heat recovery device for the vehicle is provided with an exhaust heat recovery circuit for recovering the exhaust heat of an internal combustion engine, i.e., a power source of traveling of the vehicle; an engine cooling water circuit for performing heat exchange with cooling water of the internal combustion engine; and the heat exchanger installed in an air conditioner for at least performing heating in the cabin. The exhaust heat recovery circuit is provided with an exhaust heat recovery unit connected to an exhaust pipe of the internal combustion engine and passing exhaust gas. Further, a heating medium is circulated through the exhaust heat recovery circuit and is circulated through the heat exchanger. Further, cooling water is circulated through an engine cooling water circuit and the heat exchanger. The heat exchanger is formed such that heat exchange can be performed respectively between three fluids of heating medium for the exhaust heat recovery, the engine cooling water and air for the air conditioner. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a waste heat recovery device such as engine exhaust and a heat exchanger therefor, and more particularly to a waste heat recovery device applied to an automotive heating device.

  Systems for recovering and reusing waste heat from engine exhaust gas have been studied in various fields such as power plants and ships. Even in automobiles, there has been proposed a conventional waste heat recovery system (apparatus) for heating (see, for example, Patent Document 1). In this system, exhaust heat from the engine is recovered into engine cooling water for heating. We are trying to improve performance. However, in such a configuration, there is a problem in that the rise in water temperature is slow and the room heating cannot be immediately effective for the following reasons. That is, as the reason 1 for the problem, the engine cooling water has a large heat capacity and is difficult to warm in the first place. The reason 2 is that the engine cooling water flows inside the engine body, so that the waste heat recovered from the exhaust gas may be taken away by the engine body.

  There has been proposed a method for avoiding such a problem (for example, see Patent Document 2). In this case, the exhaust heat recovery circuit is not routed through the engine cooling water by a heat pipe that is independent from the engine cooling water circuit. A method of directly heating the air and using it for room heating has been considered. However, this method limits the use range of the exhaust heat to indoor heating, resulting in a system that cannot effectively use the exhaust heat at the time when heating is not required such as in summer.

JP-A-2-299922 JP-A-3-128719

  The present invention has been made in view of the above-described circumstances, and has a system (apparatus) that has immediate effect on heating performance and can effectively use exhaust heat throughout the year, and heat for heating a vehicle interior for realizing the system. The purpose is to provide an exchanger.

  Another object of the present invention is a heat exchanger capable of effectively utilizing the heat of a hot fluid by allowing heat exchange between three different temperature fluids, for example, an exhaust of a vehicle engine. Another object of the present invention is to provide a heat exchanger that can be used in a waste heat recovery device or the like for efficiently recovering waste heat from engine cooling water.

  In the first aspect of the present invention, in order to achieve the above-described object, the vehicle waste heat recovery device 10 recovers exhaust heat of an internal combustion engine (engine) 15 that is a power source for traveling of the vehicle. An exhaust heat recovery circuit 2, an engine cooling water circuit 1 for exchanging heat with the cooling water of the internal combustion engine 15, and a heat exchanger 6 incorporated in an air conditioner 8 that at least heats the vehicle interior. In the vehicle waste heat recovery apparatus 10, the exhaust heat recovery circuit 2 includes an exhaust heat recovery unit 4 connected to the exhaust pipe 3 of the internal combustion engine 15 and through which the exhaust passes, and further, the exhaust heat A heat medium flows through the recovery circuit 2 and can exchange heat with the exhaust gas in the exhaust heat recovery unit 4, the heat medium flows through the heat exchanger 6, and the cooling water is supplied from the engine cooling water circuit. 1 and the heat exchanger 6 are distributed. The heat exchanger is formed so that heat can be exchanged between three fluids of the exhaust heat recovery heat medium, the engine cooling water, and the air for the air conditioner. .

  By configuring in this way, the exhaust heat recovery circuit 2 is independent of the engine cooling circuit 1 and therefore has a relatively smaller heat capacity than the engine cooling circuit and is not affected by the engine main body. When the temperature of the vehicle interior becomes higher than that of the engine cooling water due to the heat recovered by the recovery unit 4 and the vehicle interior heating is necessary, such as in winter, the conventional exhaust heat is recovered in the cooling water of the engine cooling system and heated. Highly effective room heating can be realized. Further, even in a situation where sufficient exhaust heat cannot be obtained, for example, when the traveling load is small, heating performance can be ensured because it can be used together with the heat of engine cooling water. Furthermore, when heating is not necessary, such as in summer, engine cooling water can be overheated by exhaust heat and engine warm-up can be accelerated, reducing engine friction and improving fuel efficiency. Exhaust heat can be used effectively throughout the year.

According to a second aspect of the present invention, in the first aspect, the heat exchanger 6 performs a heat exchange between the heat medium for exhaust heat recovery and the air for the air conditioner. A heat exchanging unit 16; and a second heat exchanging unit 17 for exchanging heat between the exhaust heat recovery heat medium and the engine coolant. In the exhaust heat recovery circuit 2, the first heat exchange unit 16 is located upstream of the second heat exchange unit 17.
According to this embodiment, a more specific embodiment of the heat exchanger provided in the waste heat recovery apparatus of the present invention is disclosed, and waste heat of engine cooling water can be used in addition to exhaust heat. The engine can be warmed up if necessary.

According to a third aspect of the present invention, in the first aspect, the heat exchanger 106 performs a heat exchange between the exhaust heat recovery heat medium and the air for the air conditioner. Between the heat exchanging part 16, the second heat exchanging part 17 for exchanging heat between the exhaust heat recovery heat medium and the engine cooling water, and the engine cooling water and the air for the air conditioner And a third heat exchanging unit 110 for exchanging heat.
According to this embodiment, for example, in a vehicle that intermittently operates an engine such as a hybrid vehicle, even when the engine is stopped and there is no exhaust heat, heating performance can be ensured by using the engine cooling water and the heat capacity of the engine body. it can.

According to a fourth aspect of the present invention, in the engine cooling water circuit 1 in the heat exchanger 106 according to the third aspect, the first heat exchange unit 16 and the third exchange unit 110 are arranged in parallel. The second heat exchanging part 17 is located on the downstream side, and the three heat exchanging parts 16, 17, 110 are integrated.
According to this form, the heat exchanger which can utilize an engine cooling water and the heat capacity of an engine main body is actualized more.

According to a fifth aspect of the present invention, the exhaust heat recovery device 4 according to any one of the first to fourth aspects, wherein the exhaust heat recovery unit 4 performs heat exchange between the exhaust gas and the heat medium. And an exhaust bypass passage 42 through which the exhaust bypasses the front exhaust heat exchanging portion 41, and an exhaust switching valve 43 that switches the exhaust passage between the exhaust heat exchanging portion 41 and the exhaust bypass passage 42. It is characterized by that.
According to this embodiment, a more specific form of the exhaust heat recovery device provided in the waste heat recovery apparatus of the present invention is disclosed.

According to a sixth aspect of the present invention, the exhaust heat recovery circuit 2 according to any one of the first to fifth aspects further includes a heat medium pump 5 and a temperature sensor 14. Features.
According to this embodiment, the exhaust heat recovery circuit of the waste heat recovery apparatus of the present invention is further embodied.

According to a seventh aspect of the present invention, in the sixth aspect, the temperature sensor 14 is installed downstream of the exhaust heat recovery device 4 and upstream of the heat exchanger 6. When the detected temperature of the heat medium exceeds the first set temperature, the blower 7 included in the air conditioner 8 is operated, and the air for the air conditioner and the exhaust heat recovery are operated in the heat exchanger 6. When heat exchange is performed with the heat medium, and the temperature of the heat medium detected by the temperature sensor 14 exceeds a second set temperature higher than the first set temperature, the exhaust switching valve 43 is operated. The exhaust heat recovery device 4 is controlled so that the exhaust passes through the exhaust bypass passage 42.
According to this embodiment, the heating air can be appropriately heated, and the heat medium temperature in the exhaust heat recovery circuit is controlled to a certain range, so that the internal pressure of the circuit rises excessively and breaks. It is possible to prevent the engine coolant temperature from becoming excessively high and overheating.

According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the exhaust heat recovery circuit 2 further includes a heat storage device 11.
According to this embodiment, since the heat stored in the heat storage device can be used when the engine is started, a more effective heating can be obtained.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, the engine coolant circuit 1 further includes a high-temperature evaporator 12.
According to this embodiment, for example, even after a feeling of heating in the passenger compartment is obtained, waste heat can be used by the Rankine cycle by combining the heat of the engine cooling water and the exhaust heat, thereby increasing the fuel consumption reduction effect of the vehicle. be able to.

  In a tenth aspect of the present invention, the heat exchanger 6 includes the first heat exchange unit 16 that performs heat exchange between the first fluid and the second fluid, the first fluid, and the third fluid. And a second heat exchanging unit 17 that performs heat exchange with the fluid. In the heat exchanger 6, the first fluid flows into the first heat exchange unit 16 and exchanges heat with the second fluid, and then flows into the second heat exchange unit 17 to exchange the first fluid. 3 is formed so as to exchange heat with three fluids.

  By comprising in this way, the heat exchanger which can utilize the heat | fever of a high temperature fluid effectively can be provided by enabling heat exchange between the fluid of three different temperatures. Such a heat exchanger can be used for a waste heat recovery device for recovering waste heat from the exhaust of the engine of the vehicle and the cooling water of the engine.

According to an eleventh aspect of the present invention, in the tenth aspect, the first heat exchanging portion 16 includes an inlet tank 64 including an inlet pipe 63 into which the first fluid flows, and the first heat exchange portion 16. A first fluid passage constituted by a plurality of tubes 61 through which a fluid passes, wherein the upstream end of the plurality of tubes 61 fluidly connects to the inlet tank 64; And second fluid passages through which the second fluid is provided with fins 62 arranged alternately. The second heat exchanging part 17 is an outer pipe 65 in which the plurality of tubes 61 are fluidly connected at their downstream ends, and has an outer pipe having an outlet pipe 69 from which the first fluid flows out, An inner pipe 66 surrounded by the outer pipe 65 to form a double pipe and through which the third fluid flows, and has an inner pipe 66 having a third fluid inlet 68c and a third fluid outlet 68d. 66, fins 67 provided between the inner tube 66 and the outer tube 65, the third fluid inlet 68c and the third fluid outlet formed so as to surround the outer tube 65. And a tank 68b fluidly connected to 68d.
According to this form, the heat exchanger which enables heat exchange between the fluid of three different temperatures is embodied more.

According to a twelfth aspect of the present invention, the heat exchanger according to any one of the tenth and eleventh aspects includes the waste heat recovery apparatuses 10 and 120 according to any one of the first to ninth aspects. It is used as the heat exchanger 6.
According to this form, the use of the heat exchanger of this invention is actualized more.

  Hereinafter, a vehicle waste heat recovery apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. 1, 2A to 2C and FIGS. 3A to 3D schematically show a first embodiment of a vehicle waste heat recovery apparatus according to the present invention. FIG. 1 shows the first embodiment of the present invention. 3A is a system diagram showing a schematic configuration of a waste heat recovery apparatus 10 according to the embodiment, and FIGS. 2A to 2C are schematic explanatory diagrams showing details of the configuration of the heat exchanger 6 included in the first embodiment. FIG. 3D is a schematic explanatory diagram illustrating details of the configuration of the exhaust heat recovery device 4 included in the first embodiment.

  First, referring to FIG. 1, a circuit of a waste heat recovery apparatus 10 according to a first embodiment of the present invention is shown. This circuit includes two circuits, a conventional engine coolant circuit 1 and an exhaust heat recovery circuit 2 that recovers waste heat from the exhaust gas of the engine 15, both of which are heat exchangers 6. Connected to. The exhaust heat recovery circuit 2 is a closed circuit in which an exhaust heat recovery device 4 mounted on an exhaust pipe 3 of the engine 15, a heat exchanger 6, and a heat medium pump 5 are connected. A heat medium circulated by the heat medium pump 5 is enclosed in the. Further, the heat exchanger 6 is disposed in the heater core portion in the conventional air conditioner 8. An exhaust heat recovery device 4 is disposed in the exhaust pipe 3 of the engine 15 where the heat medium is heated by the exhaust gas. The heat medium heated by the exhaust heat recovery device 4 is pumped by the heat medium pump 5 through the pipes constituting the exhaust heat recovery circuit 2 and sent to the heat exchanger 6.

  The engine coolant circuit 1 is connected to the main coolant circuit of the engine 15 itself. As shown in FIG. 1, the main cooling water circuit includes a radiator 21, a cooling water pump 22, a temperature control valve 23, and the like. In the main coolant circuit, coolant flows from the coolant pump 22 in the order of the engine 15, the radiator 21, and the temperature control valve 23. When the engine coolant temperature is low, the coolant is controlled so as to bypass the bypass passage 24 of the radiator 21. In the present embodiment, as shown in FIG. 1, the engine coolant circuit 1 is connected to the outlet side of the engine 15 and the suction side of the coolant pump 22, and the coolant is pumped by the coolant pump 22. The engine coolant circuit 1 is circulated. Therefore, the coolant pump 22 and the engine 15 are included in the main coolant circuit and also in the engine coolant circuit 1.

2A is a front view of the heat exchanger 6 included in the waste heat recovery apparatus 10 of the first embodiment, FIG. 2B is a cross-sectional view taken along line X2b-X2b in FIG. 2A, and FIG. 2C is X2c- in FIG. It is X2c sectional drawing.
As shown in FIG. 2B, the heat exchanger 6 has a first heat exchange section (A section) 16 that exchanges heat between the heat medium and heating air, and second heat that exchanges heat between the heat medium and engine coolant. The A section 16 is located upstream of the B section 17 in the heat medium flow path. The heating medium that has entered the heat exchanger 6 is heated in the A section 16 when the outside air temperature is low, such as in winter, and the heating air blown by the air conditioner blower 7 in the air conditioner 8 is required. Then, the exhaust heat recovery circuit 2 is circulated to the heat medium pump 5 through the B part 17. The heat exchanger 6 is made of aluminum having good thermal conductivity, and the A portion 16 includes a heat medium passage constituted by a plurality of tubes 61, and an air side passage provided with fins 62 arranged alternately with the tubes 61. The inlet pipe 63 for introducing the heat medium and the inlet tank 64 are configured.

  The tube 61 of the A portion 16 of the heat exchanger 6 is a straight pipe having a substantially rectangular cross section, and one end portion on the upstream side of the plurality of tubes 61 has an inlet tank as shown in FIG. 2A. The outer periphery of each tube 61 is joined in a sealed state to the inlet tank 64 by welding, brazing, or the like. The plurality of tubes 61 are arranged at substantially equal intervals and in parallel, and it is preferable that the fins 62 are joined and arranged between the adjacent tubes 61, but they are not joined but are in contact with each other. You can just be there. The other end portion on the downstream side of the plurality of tubes 61 is inserted into the outer tube 65 having an open top as shown in FIG. 2B in the same manner as the upstream end portion. The outer periphery of each tube 61 is joined to the outer tube 65 in a sealed state by welding, brazing, or the like.

  The B portion 17 is a double tubular heat exchanger, and as shown in FIG. 2B, an engine cooling water passage 68a surrounding the cylindrical outer tube 65, the cylindrical inner tube 66, the fins 67, and the outer tube 65. A tank 68b for forming the cooling water, pipes 68c and 68d for introducing and leading out the cooling water, and an outlet pipe 69 for guiding the heat medium. A plurality of tubes 61 are inserted into the outer tube 65 as shown in FIG. 2A, so that the outer tube 65 communicates with the plurality of tubes 61 of the A portion 16, and the heat medium is the outer tube 65 and the inner tube. It is discharged out of the heat exchanger 6 through an outlet pipe 69 communicating with the outer pipe 65 through the space 66. The cooling water flows in from the introduction pipe 68c, passes through the inner pipe 66 and the engine cooling water passage 68a in parallel, and at that time, exchanges heat with the heat medium passing through the outer pipe 65 and flows out from the outlet pipe 68d.

  The fins 67 are radially joined to the inner tube 66 so as to surround the inner tube 66, and increase the heat transfer area with the heat medium. In the present embodiment, the tank 68b has a substantially elongated rectangular parallelepiped shape, is formed so as to surround the outer pipe 65, and forms an engine coolant passage 68a between the outer pipe 65 and the tank 68b. A plurality of tubes 61 of the A portion 16 are inserted into the upper cover 70 of the tank 68b, and the upper cover 70 is joined to the outer periphery of the tank 68b by welding, brazing, or the like to seal the tank 68b.

  3A is a front view of the exhaust heat recovery device 4 included in the waste heat recovery apparatus 10 of the first embodiment, and FIG. 3B is a cross-sectional view taken along line X3b-X3b in FIG. 3A. 3C is a cross-sectional view taken along the line X3c-X3c in FIG. 3B and shows the exhaust flow path of the exhaust heat recovery device 4 as viewed from the upstream side of the exhaust gas flow path. FIG. 3D is a cross-sectional view taken along the line X3d-X3d in FIG. 3B and shows the exhaust flow path of the exhaust heat recovery device 4 viewed from the downstream side.

  The exhaust heat recovery device 4 is preferably made of stainless steel mainly having high corrosion resistance. As shown in FIG. 3B, the exhaust heat recovery device 4 and an exhaust bypass formed by the cylindrical second pipe 51 are used. An exhaust switching (bypass) valve 43 is provided on the downstream side of the passage 42 and further in these exhaust gas passages. When excessive exhaust heat is generated during high-load operation of the engine, the engine cooling water is hot. In order to prevent overheating, the exhaust passage can be switched from the passage of the heat exchanging portion 41 to the exhaust bypass passage 42 so that the exhaust heat is not recovered. FIG. 3D shows a state in which the exhaust gas switching valve 43 fully closes the exhaust bypass passage 42. The heat exchanging portion 41 includes a cylindrical first pipe 44, and a plurality of small diameter pipes 46 are installed in the first pipe 44 at substantially equal intervals in parallel as can be seen in FIGS. 3C and 3D. The exhaust gas flows through these small-diameter pipes 46, and the heat medium flowing in from the inlet 47 and flowing out from the outlet 48 flows through the outer space 49, and heat is exchanged between the exhaust gas and the heat medium. . Engine cooling water may be used as the heat medium, but heat medium oil having a high boiling point such as silicon-based oil can recover heat at a higher temperature without making the exhaust heat recovery circuit 2 high pressure resistant. Therefore, it is desirable in terms of cost and heating performance.

  The exhaust heat recovery device 4 has two pipes 44 and 51 running in parallel, and flanges 52 and 53 are joined to both ends of the two pipes 44 and 51 by welding or the like as shown in FIG. 3B. Has been. The flanges 52 and 53 are provided with a plurality of bolt holes (two in the present embodiment, but may be more than two) and can be easily connected to the exhaust pipe 3. The exhaust switching (bypass) valve 43 has a simple configuration in which a disc-shaped valve body is attached to a rotating shaft in accordance with the shape of the exhaust flow path as shown in the figure. It is preferably formed so as to be within the thickness range. Therefore, the valve body can be operated in the exhaust pipe 3. In the present embodiment, the exhaust gas switching valve 43 is driven by an electric motor 45 and rotates an exhaust flow path by rotating 180 degrees. As shown in FIG. 3A, the electric motor 45 of the exhaust gas switching valve 43 is provided with a pedestal on the flange 53 and is installed on the pedestal so as to maintain the airtightness of the exhaust pipe.

Next, the operation of the waste heat recovery apparatus 10 of the first embodiment will be described.
(If the amount of heat required for indoor heating in the winter season <exhaust heat)
The case described below is a case where the passenger compartment is heated in winter, and the amount of heat required for indoor heating is smaller than the amount of heat recovered from the exhaust gas. After the engine is started, the exhaust that has become hot heats the heat medium that circulates in the exhaust heat recovery circuit 2 by the exhaust heat recovery device 4 (heat exchange unit 41). The heat medium is sent to the heat exchanger 6 by the heat medium pump 5. The temperature of the heat medium is detected by the temperature sensor 14 shown in FIG. 1. When the heat medium temperature exceeds a predetermined temperature (for example, 60 ° C.), the air-conditioning blower 7 operates and the heat exchanger 6 A Blowing is started toward the part 16, the heat medium and the heating air exchange heat in the A part 16, and heating of the vehicle interior is started by the heated heating air.

Thereafter, when the passenger compartment is sufficiently heated, the air-conditioning blower 7 reduces the air volume, and the air mix door 9 operates in a closing direction with respect to the heat exchanger 6 to reduce the air flow into the passenger compartment. Adjust the temperature in the passenger compartment. For this reason, the heat exchange amount in the A part 16 of the heat exchanger 6 decreases, and the heat medium flows into the B part 17 of the heat exchanger 6 while maintaining a high temperature, and the engine cooling water is overheated. Thereby, exhaust heat is utilized for engine warm-up.
Further, when the operation of the vehicle is continued and the heat medium temperature in the exhaust heat recovery circuit 2 exceeds a predetermined temperature (for example, 150 ° C.), the exhaust gas switching valve 43 provided in the exhaust heat recovery device 4 exhausts the exhaust gas. It operates in the direction in which the bypass passage 42 is opened, and the amount of exhaust gas flowing into the heat exchanging portion 41 is reduced, thereby suppressing the amount of exhaust heat recovered. As a result, the temperature of the heat medium in the exhaust heat recovery circuit 2 is controlled within a certain range, so that the internal pressure of the circuit 2 rises excessively to cause damage, or the engine cooling water temperature becomes excessively high and overheats. Can be prevented.

(If the amount of heat required for indoor heating in winter> exhaust heat)
The case described below is a case where the passenger compartment is heated in winter and the amount of heat required for indoor heating is larger than the amount of heat recovered from the exhaust gas. When the amount of heat required for room heating is greater than the amount of heat recovered from the exhaust gas, such as at extremely low temperatures or when the vehicle's running load is small and sufficient exhaust heat cannot be obtained, the heat of the heat medium is high. All of the A part 16 of the exchanger 6 is deprived of the air for heating, and the temperature of the heat medium after passing through the A part 16 decreases to almost the same as the outside air temperature. In such a case, when the temperature of the engine cooling water rises while the maximum heating by the exhaust heat is continued and becomes higher than the heat medium temperature in the B section 17 of the heat exchanger 6, heat exchange is performed. Heat is recovered from the engine coolant to the heat medium side in the B part 17 of the heat exchanger 6, and then the heat medium circulated to the exhaust heat recoverer 4 also recovers the exhaust heat and then heated again in the A part 16 of the heat exchanger 6. Overheat the working air. Heating performance is ensured by receiving heat from both exhaust gas and engine coolant in this manner.

(When indoor heating is not required in summer, etc.)
When indoor heating is not required, such as in the summer, the heat medium flows into the B portion 17 of the heat exchanger 6 while keeping the high temperature without being deprived of heat in the A portion 16 of the heat exchanger 6, and the engine cooling water. The engine is warmed up by heating. As a result, engine warm-up can be accelerated, so that engine friction can be reduced and fuel consumption can be improved.

  4A to 4D show a heat exchanger 106 provided in the exhaust heat recovery apparatus according to the second embodiment of the present invention. 4A is a front view of the heat exchanger 106 included in the waste heat recovery apparatus according to the second embodiment, FIG. 4B is a cross-sectional view taken along line X4b-X4b in FIG. 4A, and FIG. 4C is X4c-X4c in FIG. It is sectional drawing. 4D is a cross-sectional view taken along the line X4d-X4d in FIG. 4B. Referring to FIGS. 4A-4D, the element parts of the heat exchanger 106 of FIGS. 4A-4D, which are the same as or similar to the element parts of the heat exchanger 6 of the first embodiment disclosed in FIGS. Are designated by the same reference numerals.

  In the second embodiment of the present invention, the heat exchanger 6 of the first embodiment and the heater core of the conventional structure are integrated, and the engine coolant of the heat exchanger 6 in the first embodiment is integrated. The passage 68a is shared with the cooling water outlet side tank of the heater core. Referring to FIG. 4B, a heat exchanger 6 'similar to the heat exchanger 6 of the first embodiment is provided on the left side, and a conventional heater core 110 is provided on the right side. Accordingly, FIG. 4A is a front view on the heat exchanger 6 'side, and FIG. 4D is a front view on the heater core 110 side. Similar to the heat exchanger 6 of the first embodiment, the heat exchanger 6 'includes an A portion 16 and a B portion 17 made of aluminum having good thermal conductivity, and the A portion 16 includes a plurality of tubes. A heat medium passage constituted by 61, an air side passage provided with fins 62 arranged alternately with tubes 61, an inlet pipe 63 for introducing a heat medium, and a tank 64. The B section 17 is also a double tubular heat exchanging section, and includes an outer pipe 65, an inner pipe 66, fins 67, a tank 68b for forming an engine cooling water passage 68a surrounding the outer pipe 65, and cooling water. The pipes 68c and 68d for introducing and leading out and the outlet pipe 69 for leading out the heat medium are further configured. The configuration of such a heat exchanger 6 'is the same as that of the heat exchanger 6 of the first embodiment already described.

  As shown in FIG. 4B, the heater core 110 is arranged alternately with the cooling water inlet pipe 112, the inlet tank 114, the cooling water passage formed by a plurality of tubes 116 communicating with the inlet tank 114, and the tubes 116. And an air side passage provided with fins 117. The tube 116 is joined to the tank 68b. The configuration of such a heater core 110 is the same as the configuration of the A section 16 that is a heat exchange section. Thus, the tank 68b is a common tank for the heat exchanger 6 'and the heater core 110.

Since the thermal refrigerant passes through the heat exchanger 6 ′ through the same route as that of the heat exchanger 6 in the first embodiment, the detailed description is omitted to avoid duplication of explanation. On the other hand, on the heat exchanger 6 ′ side, the engine cooling water flows in from the introduction pipe 68c and passes through the inner pipe 66 and the engine cooling water passage 68a in parallel. It exchanges and flows out from the outlet pipe 68d. On the other hand, on the heater core 110 side, the engine cooling water flows from the inlet pipe 112, passes through the tube 116, exchanges heat with air-conditioning / heating air, and flows into the tank 68b (cooling water passage 68a). 68d flows out.
The configuration of the exhaust heat recovery apparatus of the present embodiment other than the above is the same as the configuration of the exhaust heat recovery apparatus 10 of the first embodiment.

FIG. 5 shows a waste heat recovery apparatus 120 according to the third embodiment of the present invention, and FIG. 5 is the same as FIG. 1 showing a schematic configuration of the waste heat recovery apparatus 120 according to the third embodiment. It is a systematic diagram. Referring to FIG. 5, the element parts of the waste heat recovery apparatus 120 of FIG. 5 that are the same as or similar to the element parts of the waste heat recovery apparatus 10 of the first embodiment disclosed in FIG. It is specified by.
In the present embodiment, the exhaust heat recovery circuit 2 has a heat storage device 11 downstream of the exhaust heat recovery device 4 and upstream of the heat exchanger 6, and the engine cooling circuit 1 is shown in Japanese Patent No. 2540738. A Rankine cycle high-temperature evaporator 12 is provided as shown in FIG. While the heat storage device 11 can store the heat recovered by the exhaust heat recovery device 4 or the heat exchanger 6, it can dissipate the stored thermal energy. Further, by providing necessary circuits and components around the heat storage device 11 and appropriately controlling them, heat storage to the heat storage device 11 and heat radiation from the heat storage device 11 can be performed as necessary. The configuration of the necessary circuits and components described above is configured by a bypass path, a control valve, and the like, and is known to those skilled in the art.

The high temperature evaporator 12 is a device that uses the recovered heat energy of the heat medium. In the example of FIG. 5, a heat energy recovery circuit 130 including the high temperature evaporator 12 is provided. For example, as shown in FIG. 5, the thermal energy recovery circuit 130 includes a pump 131, a turbine 132, and a condenser 133, and another heat medium such as steam is enclosed in the circuit 130. Another heat medium is heated in the high-temperature evaporator 12 to evaporate and expand, and drives the turbine 132. Thereafter, another heat medium is cooled by the condenser 133 to become a liquid, sucked by the pump 131, sent to the high-temperature evaporator 12, and circulates in this circuit 130. Such a thermal energy recovery circuit 130 is known and may be other energy recovery circuits known to those skilled in the art. In addition, the exhaust heat recovery circuit 2 has a path through which the heat medium bypasses the high-temperature evaporator 12, is controlled as appropriate, and is controlled so as to recover thermal energy in the high-temperature evaporator 12 as necessary. Also good.
Except for the above, the configuration of the exhaust heat recovery apparatus 120 of the present embodiment is the same as the configuration of the exhaust heat recovery apparatus 10 of the first embodiment.

Next, effects and operations of the above embodiment will be described. The following effects can be expected from the waste heat recovery apparatus according to the first embodiment of the present invention.
Since the exhaust heat recovery circuit 2 is independent of the engine cooling circuit 1, the heat capacity is relatively smaller than that of the engine cooling circuit and is not affected by the engine body, so the heat medium is recovered by the exhaust heat recovery unit 4. If the temperature rises faster than the engine cooling water due to heat, and vehicle interior heating is required, such as in the winter, indoor heating that is more effective than the conventional method of collecting exhaust heat in the cooling water of the engine cooling system and heating it. Can be realized.
-Heating performance can be ensured because it can be used together with the heat of engine cooling water even in a situation where sufficient exhaust heat cannot be obtained, such as a small driving load.
・ Furthermore, when heating is unnecessary such as in summer, engine cooling water can be heated by exhaust heat and engine warm-up can be accelerated, so engine friction can be reduced and fuel efficiency can be improved. .
・ As mentioned above, exhaust heat can be used effectively throughout the year.

In addition to the effects of the first embodiment, the following effects can be expected from the waste heat recovery apparatus according to the second embodiment of the present invention.
-For example, in a vehicle such as a hybrid vehicle that intermittently operates an engine, even when the engine is stopped and there is no exhaust heat, heating performance can be ensured by utilizing the engine cooling water and the heat capacity of the engine body.

In addition to the effects of the first embodiment, the following effects can be expected from the waste heat recovery apparatus according to the third embodiment of the present invention.
・ When the engine is started, the heat stored in the heat storage device can be used, so that more effective heating can be obtained.For example, the engine cooling water heat and exhaust heat can be obtained even after a feeling of heating in the passenger compartment is obtained. Moreover, since waste heat can be utilized by Rankine cycle, the fuel consumption reduction effect of a vehicle can be increased.

In the above description, the waste heat recovery apparatus of the present invention and the heat exchanger therefor have been described for vehicles. However, the apparatus may be used for applications other than those for vehicles.
Further, in the embodiments described above or shown in the accompanying drawings, the waste heat recovery apparatus of the present invention is basically described as having a minimum number of components, and the waste heat recovery apparatus Various functional elements such as accessory elements and control elements may be additionally incorporated in the present invention according to functional, control, and application requirements, and further, the configuration of the waste heat recovery apparatus, The arrangement, arrangement, etc. may be changed or modified as necessary.

Further, in the above embodiment, materials such as a heat exchanger, an exhaust heat recovery device, and a heat medium are defined, but these materials are different and inexpensive depending on cost, use conditions, design conditions, etc. It may be replaced by expensive or different material properties.
Further, in the embodiment described above or shown in the attached drawings, the specifications of the shape, arrangement, configuration, structure, connection type, etc. of the heat exchanger, the exhaust heat recovery device, and their components are concrete. However, the present invention is not limited to this, and may be another specification that can be considered by those skilled in the art.

  The above-described embodiment is an example of the present invention, and the present invention is not limited by the embodiment, but is defined only by matters described in the claims, and other embodiments than the above are also possible. It can be implemented.

FIG. 1 is a system diagram showing a schematic configuration of a waste heat recovery apparatus 10 according to a first embodiment of the present invention. FIG. 2A is a front view schematically illustrating the details of the configuration of the heat exchanger 6 included in the waste heat recovery apparatus 10 of the first embodiment. 2B is a cross-sectional view taken along line X2b-X2b in FIG. 2A. 2C is a cross-sectional view taken along the line X2c-X2c in FIG. 2A. FIG. 3A is a front view schematically illustrating details of the configuration of the exhaust heat recovery device 4 included in the first embodiment. 3B is a cross-sectional view taken along the line X3b-X3b in FIG. 3A. 3C is a cross-sectional view taken along the line X3c-X3c in FIG. 3B. 3D is a cross-sectional view taken along the line X3d-X3d in FIG. 3B. FIG. 4A is a front view of the heat exchanger 106 included in the exhaust heat recovery apparatus according to the second embodiment of this invention. 4B is a cross-sectional view taken along the line X4b-X4b in FIG. 4A. 4C is a cross-sectional view taken along the line X4c-X4c in FIG. 4A. 4D is a cross-sectional view taken along the line X4d-X4d in FIG. 4B. FIG. 5 shows a waste heat recovery apparatus according to a third embodiment of the present invention, and is a system diagram similar to FIG. 1 showing a schematic configuration.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine cooling water circuit 2 Exhaust heat recovery circuit 3 Exhaust pipe 4 Exhaust heat recovery device 5 Heat medium pump 6 Heat exchanger 7 Blower 8 Air-conditioning device 9 Air mix door 10 Waste heat recovery device 14 Temperature sensor

Claims (12)

An exhaust heat recovery circuit (2) for recovering exhaust heat of the engine (15), which is a power source for running the vehicle;
An engine coolant circuit (1) for exchanging heat with the coolant of the engine (15);
A heat exchanger (6) incorporated in an air conditioner (8) for heating at least the interior of the vehicle;
In the vehicle waste heat recovery device (10), comprising:
The exhaust heat recovery circuit (2) includes an exhaust heat recovery device (4) connected to the exhaust pipe (3) of the engine (15) and through which the exhaust passes, and further the exhaust heat recovery circuit In (2), the heat medium circulates so that heat can be exchanged with the exhaust in the exhaust heat recovery unit (4).
The heat medium circulates through the heat exchanger (6), and the cooling water circulates through the engine cooling water circuit (1) and the heat exchanger (6),
The heat exchanger (6) is formed such that heat can be exchanged between three fluids of the exhaust heat recovery heat medium, the engine cooling water, and the air for the air conditioner (8). Waste heat recovery device characterized by that. The heat exchanger (6) includes a first heat exchange unit (16) that performs heat exchange between the exhaust heat recovery heat medium and the air for the air conditioner, and the exhaust heat recovery heat medium. A second heat exchange section (17) for exchanging heat with the engine coolant,
2. The waste heat according to claim 1, wherein in the exhaust heat recovery circuit (2), the first heat exchanging part (16) is located upstream of the second heat exchanging part (17). Recovery device. The heat exchanger (106)
A first heat exchange section (16) for exchanging heat between the exhaust heat recovery heat medium and the air for the air conditioner;
A second heat exchange section (17) for exchanging heat between the exhaust heat recovery heat medium and the engine coolant;
A third heat exchange section (110) for exchanging heat between the engine coolant and the air for the air conditioner;
The waste heat recovery apparatus according to claim 1, comprising:   In the engine coolant circuit (1) in the heat exchanger (106), the first heat exchanging part (16) and the third exchanging part (110) are arranged in parallel, and the second heat exchanger (106) is disposed downstream of the second heat exchanging part (16). The waste heat recovery apparatus according to claim 3, wherein the heat exchange section (17) is located and the three heat exchange sections (16, 17, 110) are integrated. The exhaust heat recovery device (4)
An exhaust heat exchange section (41) for exchanging heat between the exhaust and the heat medium;
An exhaust bypass passage (42) through which the exhaust bypasses the front exhaust heat exchanger (41);
An exhaust switching valve (43) for switching an exhaust passage between the exhaust heat exchange section (41) and the exhaust bypass passage (42);
The waste heat recovery apparatus according to any one of claims 1 to 4, further comprising:   The waste heat recovery device according to any one of claims 1 to 5, wherein the exhaust heat recovery circuit (2) further includes a heat medium pump (5) and a temperature sensor (14). . The temperature sensor (14) is installed downstream of the exhaust heat recovery device (4) and upstream of the heat exchanger (6),
When the temperature of the heat medium detected by the temperature sensor (14) exceeds the first set temperature, the blower (7) included in the air conditioner (8) is operated and the heat exchanger (6) Heat exchange is performed between the air for the air conditioner and the heat medium for exhaust heat recovery, and the temperature of the heat medium detected by the temperature sensor (14) is higher than the first set temperature. The exhaust gas switching valve (43) is operated when a set temperature is exceeded, and the exhaust heat recovery device (4) controls the exhaust gas to pass through the exhaust bypass passage (42). The waste heat recovery device described in 1.   The waste heat recovery device according to any one of claims 1 to 7, wherein the exhaust heat recovery circuit (2) further comprises a heat storage device (11).   The waste heat recovery device according to any one of claims 1 to 8, wherein the engine coolant circuit (1) further comprises a high-temperature evaporator (12). A first heat exchange section (16) that exchanges heat between the first fluid and the second fluid, and a second heat that exchanges heat between the first fluid and the third fluid. In the heat exchanger (6) comprising the exchange part (17),
The first fluid flows into the first heat exchange part (16) and exchanges heat with the second fluid, and then flows into the second heat exchange part (17) and enters the third fluid. A heat exchanger characterized by exchanging heat with. The first heat exchange section (16)
An inlet tank (64) comprising an inlet pipe (63) into which the first fluid flows;
A first fluid passage constituted by a plurality of tubes (61) through which the first fluid passes, wherein upstream ends of the plurality of tubes (61) are fluidly connected to the inlet tank (64). A fluid passage;
A second fluid passage through which the second fluid comprises fins (62) arranged alternately with the tubes (61);
It has
The second heat exchange section (17)
An outer tube (65) in which the plurality of tubes (61) are fluidly connected at their downstream ends, and an outer tube having an outlet pipe (69) through which the first fluid flows;
An inner pipe (66) surrounded by the outer pipe (65) to form a double pipe and through which the third fluid flows, the third fluid inlet (68c) and the third fluid outlet An inner tube (66) having (68d);
A fin (67) provided between the inner tube (66) and the outer tube (65);
A tank (68b) formed to surround the outer pipe (65) and fluidly connected to the third fluid inlet (68c) and the third fluid outlet (68d);
The heat exchanger according to claim 10, comprising:   It is used as said heat exchanger (6) which the waste heat recovery apparatus (10, 120) as described in any one of Claim 1 to 9 comprises, In any one of Claim 10 or 11 characterized by the above-mentioned. The described heat exchanger.

Images