JP2007001514A - Heat exchanger for fuel cell electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger for a fuel cell electric vehicle capable of realizing compatibility between reduction of a removal heat amount heat-released to a coolant and reduction of noise as a problem inherent to the fuel cell electric vehicle. <P>SOLUTION: In the heat exchanger for the fuel cell electric vehicle for adjusting a temperature of air fed to a fuel cell stack to a suitable temperature, variation is given to thickness of a portion applied with air and a portion not applied with air and the thickness of the portion applied with air is made thinner than the thickness of the portion not applied with air. For example, the thickness of a vehicle front part F of an intake side manifold part 14 and an exhaust side manifold part 16 is made thinner than the thickness of a vehicle rear part E. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat exchanger for a fuel cell vehicle, and more particularly, to a technique for reducing heat removal and noise.

  In order to address the problems of air pollution caused by exhaust gas from automobiles and global warming caused by carbon dioxide in recent years, fuel cell automobiles equipped with fuel cells that enable clean exhaust and highly efficient energy conversion have attracted attention.

  Fuel cell vehicles are attracting attention as well as their environmental performance and quietness due to the absence of an internal combustion engine, and their components are required to have higher quietness than those for conventional internal combustion engine vehicles. Yes. The main noise generating sources in question include air supply parts that supply air to the fuel cell stack, that is, a compressor, a silencer, an after cooler, and piping connecting them.

  As means for reducing sound from these automobile components, sound reduction means such as increasing the thickness (thickness) of components, changing the natural frequency, reducing radiated sound, etc. are effective. It is.

  On the other hand, fuel cell vehicles have a more complex system than internal combustion engine vehicles, have a large number of components, and generate large amounts of heat in the fuel cell stack body and auxiliary machinery. It has become. Therefore, fuel cell vehicles are required to reduce the amount of heat removed, which is the amount of heat that moves from the component to be cooled to the refrigerant. As a heat extraction reduction means, for example, one of the solution measures is to efficiently dissipate heat to the atmosphere.

Thus, it is necessary to achieve noise reduction for air components for fuel cell vehicles by a technique that does not hinder heat dissipation to the outside air. For example, there is an oil pan for automobiles described in Patent Document 1 in view of sound insulation performance and heat dissipation performance to the outside air. Such an oil pan for automobiles has a sound insulation structure of an oil pan divided into two parts, a shallow bottom part and a deep bottom part, and by insulating only the side surface of the deep bottom part, a sound insulation performance of 90% or more is obtained compared to when covering the whole. There is knowledge that
JP-A-8-254111 (refer to page 2 and page 3, FIG. 2 and FIG. 3)

  By the way, in a fuel cell vehicle, it is common to mount a water-cooled cooler instead of air-cooled cooling that is common in mass-produced vehicles because of the size of heat dissipation requirements. In addition, in fuel cell vehicles, the required heat dissipation amount of the entire vehicle components is larger than that of mass-produced vehicles, and reduction of the amount of heat removed from the water-cooled air cooler to the refrigerant has been an issue.

  On the other hand, as a problem specific to a fuel cell vehicle, there is a high noise requirement in addition to the heat dissipation problem. As a countermeasure against noise, it is effective to increase the thickness of the constituent members, change the natural frequency, and reduce the radiated sound as described above, but the sound insulation due to the thickening has a heat insulating effect as the weight increases. Therefore, there is a problem in that heat radiation to the outside air is hindered and the amount of heat removed to the refrigerant is increased. For this reason, there has not been a heat exchanger with a sound insulation mechanism that focuses on the heat dissipation effect to the atmosphere, which is a problem peculiar to fuel cell vehicles.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a heat exchanger for a fuel cell vehicle, which is a problem specific to a fuel cell vehicle, and can achieve both a reduction in the amount of heat released to the refrigerant and a reduction in noise.

  The present invention is a heat exchanger for a fuel cell vehicle which is arranged at a place where an air flow is generated and adjusts the temperature of air supplied to a fuel cell stack to an appropriate temperature. It is characterized in that the thickness of the part not exposed to air is changed, and the thickness of the part exposed to the air is made thinner than the thickness of the part not exposed to the air.

  According to the heat exchanger for a fuel cell automobile of the present invention, the thickness of the portion that is exposed to air is made thinner than the thickness of the portion that is not exposed to air, thereby effectively obtaining a heat dissipation effect to the outside air, The amount of heat removed to the refrigerant flowing in the heat exchanger can be reduced.

  Further, according to the heat exchanger for a fuel cell vehicle of the present invention, since the thickness of the portion of the heat exchanger is changed to make the thickness non-uniform, the eigenvalue determined by the thickness is Without having, air column resonance can be reduced.

  Therefore, according to the present invention, it is possible to provide a heat exchanger for a fuel cell vehicle having an effective sound insulation performance in addition to efficiently obtaining a heat radiation effect to the outside air and reducing a heat extraction amount to the refrigerant. Can do.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

“Embodiment 1”
First, the system configuration of the fuel cell air supply device will be described. FIG. 1 is a system diagram of an air supply device for a fuel cell.

  The air sent to the fuel cell stack 9 is introduced from a resin air duct 4 which is a sound deadening means to reduce sound, and then impurities such as nitrogen oxides and sulfur oxides are removed by the chemical filter 5, and the air compressor 6, pressure pulsation is reduced by a silencer 7, which is another sound reduction device, and then adjusted to an appropriate temperature by a heat exchanger 8 and supplied to the fuel cell stack 9.

  The compressor 6, the fuel cell stack 9, and the heat exchanger 8, which are heat generating components, require cooling water flowing through the refrigerant flow path 3 in order to dissipate heat. The cooling water is cooled by receiving heat from the above components and then radiating heat to the outside air via the radiator 10. In FIG. 1, reference numeral 1 denotes an air flow path, and reference numeral 2 denotes a hydrogen flow path.

  Next, an example of mounting the above-described fuel cell air supply device on a vehicle (automobile) will be described. FIG. 2 is a schematic view showing an example of mounting the fuel cell air supply device on a vehicle.

  Except for the parts specific to the fuel cell vehicle such as the fuel cell stack 9, the position of the passenger 12 who rides on the vehicle 11 is basically the same as the mass production vehicle (internal combustion engine vehicle). The fuel cell stack 9 is installed at the feet of the passenger 12. The main parts excluding the fuel cell stack 9 are mounted on the front part of the vehicle corresponding to the engine room of a mass-produced vehicle. The outside air is forcibly introduced by a difference between the outside air from the front of the vehicle and the relative speed of the vehicle, and a radiator fan 13 mounted behind the radiator 10.

  Next, the heat exchanger (air cooling device) for the fuel cell vehicle according to the present embodiment will be described. FIG. 3 is a perspective view showing an example of a heat exchanger for a fuel cell vehicle.

  As shown in FIG. 2, the heat exchanger 8 of the present embodiment is disposed in front of the vehicle where the air flow is generated and behind the radiator fan 13. The heat exchanger 8 is cooled by receiving air supplied from the radiator fan 13 and air generated by traveling the vehicle. The direction of air flow is indicated by an arrow X in FIG.

  As shown in FIG. 3, the heat exchanger 8 includes an intake side manifold portion 14 installed toward the vehicle side surface (the surface side facing the vehicle width direction orthogonal to the vehicle traveling direction), and the intake side manifold portion 14. The heat exchanger main body 15 into which air flows into the inside thereof, and an exhaust side manifold portion 16 for discharging (exhausting) air from the heat exchanger main body 15 to the outside.

  In the heat exchanger 8 of the present embodiment, the thickness of the portion that is exposed to air and the portion that is not exposed to air are changed, and the thickness of the portion that is exposed to air is made larger than the thickness of the portion that is not exposed to air. It is thin. Specifically, among the intake side manifold portion 14 and the exhaust side manifold portion 16, the thickness (thickness) of the vehicle front portion F where the air hits is made thinner than the thickness of the vehicle rear portion E where the air does not hit. Yes. It should be noted that the boundary between the portion that is exposed to air and the portion that is not exposed to air is not required to a position that strictly separates a position where no air is applied and a position where the air is applied.

  Thus, in order to change the thickness of the intake side manifold portion 14 and the exhaust side manifold portion 16, as shown in FIG. 4, the center positions C1 and C2 of the pipe inner diameter and the pipe outer diameter are eccentrically formed. To change the thickness. That is, by shifting the center position C2 of the pipe outer diameter relative to the center position C1 of the pipe inner diameter to the vehicle rear side with respect to the vehicle traveling direction, the thickness of the vehicle front portion F where the air hits does not hit the air. It is made thinner than the thickness of the vehicle rear portion E.

  By the way, it is generally known that the main sounding portions of the heat exchanger 8 are from the planes of the intake side manifold portion 14, the exhaust side manifold portion 16 and the heat exchanger body 15. Sound generation from the intake side manifold portion 14 and the exhaust side manifold portion 16 is mainly caused by air column resonance due to fluid movement in the pipe and sound generation from vortices generated due to fluid movement. Resonance is generated when the sounding body vibrates when it receives a sound of the same frequency as that produced when it vibrates. The pipe has an eigenvalue determined by its thickness and material, and emits air column resonance.

  However, according to the heat exchanger 8 of the present embodiment, the thickness of the vehicle front portion F where the air in the intake side manifold portion 14 and the exhaust side manifold portion 16 hits the wall thickness of the vehicle rear portion E where the air does not hit. Since it is thinner, it is possible to obtain a heat radiation effect due to the inflow of outside air from the front accompanying traveling, and a heat radiation effect to the outside air can be efficiently obtained in a thin portion where the air hits, and the heat flows in the heat exchanger 8. The amount of heat removed to the refrigerant can be reduced.

  Further, according to the heat exchanger 8 of the present embodiment, since the thickness is changed by the portions of the intake side manifold portion 14 and the exhaust side manifold portion 16 to make the thickness uneven, It is possible to reduce the above-described air column resonance without having the eigenvalue determined by the above.

  Further, according to the heat exchanger 8 of the present embodiment, the amount of reduction in sound emission from the vortex generated by the fluid movement inside the manifold is increased in the vehicle interior direction (vehicle rear portion E). Is effectively reduced. Generally, the generation of radiated sound accompanying fluid movement has a high frequency and is captured by the occupant as an abnormal noise.

  Further, according to the heat exchanger 8 of the present embodiment, since the thickness is changed by decentering the center positions C1 and C2 of the pipe inner diameter and the pipe outer diameter, the thickness is not uniform. Piping can be easily manufactured. In particular, if the center positions C1 and C2 of the pipe inner diameter and the pipe outer diameter are decentered, the wall thickness continuously changes in the circumferential direction, so that the effect of reducing air column resonance is great.

  As described above, according to the heat exchanger 8 of the present embodiment, it is possible to provide a vehicle heat exchanger having an effective sound insulation performance in addition to reducing the amount of heat extracted from the refrigerant.

“Embodiment 2”
In the present embodiment, as shown in FIG. 5, the heat exchanger 8 is arranged behind the radiator fan 13, and the air (cold air) forcedly blown from the radiator fan 13 and the air received by the vehicle running are This is an example of heat exchange.

  In the heat exchanger 8 of this embodiment, in addition to the configuration of the first embodiment in which the thicknesses of the intake side manifold portion 14 and the exhaust side manifold portion 16 are not uniform, the portion of the heat exchanger main body 15 that is exposed to air And the thickness of the part where the air does not hit is changed. Specifically, the thickness of the front surface portion F excluding the back surface portion B (shaded in FIG. 5) of the heat exchanger body 15 facing the passenger compartment side opposite to the vehicle traveling direction is the thickness of the back surface portion B. It is thinner.

  According to the heat exchanger 8 of the present embodiment, the heat radiation effect to the outside air can be obtained more efficiently by the air forcedly blown by the radiator fan 13 in addition to the air blown by traveling of the vehicle. In addition to a reduction in the amount of heat extracted, effective sound insulation performance is also obtained. In particular, by increasing the thickness of the portion of the heat exchanger body 15 that is disposed in front of the driver that has a large influence on the vehicle interior noise and that faces the vehicle interior, high sound insulation can be obtained.

  Further, according to the heat exchanger 8 of the present embodiment, it is possible to reduce the amount of heat removed to the running refrigerant that requires a greater cooling request than when the vehicle is idle.

  In FIG. 5, only the back portion B of the heat exchanger body 15 facing the passenger compartment is thickened and the other portions are thinned. However, as shown in FIG. The thickness of the vehicle front portion F that receives air forcedly blown by the fan 13 may be reduced, and the thickness of other portions may be increased. By so doing, vehicle interior noise can be further reduced.

“Embodiment 3”
In the present embodiment, as shown in FIG. 7, the heat exchanger 8 is arranged such that the intake side manifold portion 14 is directed in the vehicle traveling direction and the exhaust side manifold portion 16 is directed to the rear opposite to the vehicle traveling direction. This is an example.

  In the heat exchanger 8 of the present embodiment, only the vehicle front portion F of the intake side manifold portion 14 and the heat exchanger main body 15 to which the air hits is made thin, and the vehicle rear portion E (see FIG. 7 (shown by shading) is thick. Due to the characteristics of the cooling device, there is a large temperature difference between the outer surface of the heat exchanger on the intake side where the fluid before cooling flows in and the discharge side where the air after cooling flows.

  According to the heat exchanger 8 of the present embodiment, the portion where the surface temperature of the heat exchanger main body 15 becomes high, that is, the intake side manifold portion 14 and its peripheral portion (the vehicle front portion F of the heat exchanger main body 15) are arranged. By installing toward the front of the vehicle where the air cooling effect can be obtained efficiently, the air cooling effect can be obtained efficiently, and the amount of heat removed to the refrigerant can be reduced.

  Note that the intake side manifold portion 14 of FIG. 7 may be disposed toward the rear of the radiator fan 13. If it does so, the air-cooling effect can be obtained much more efficiently and the heat exchanger for vehicles with little heat removal to a refrigerant can be obtained.

  The specific embodiments to which the present invention is applied have been described above. However, the present embodiment is merely an example, and the present invention is not limited to these embodiments.

It is a system diagram of an air supply device for a fuel cell. It is the schematic which showed the example of mounting to the vehicle of the air supply apparatus for fuel cells. An example of the heat exchanger for fuel cell vehicles is shown, (A) is a perspective view of a heat exchanger, and (B) is a sectional view of a manifold part. It is sectional drawing which shows the example which gave the change to the thickness of the manifold part by shape | molding eccentrically the center position of piping inner diameter and piping outer diameter. It is a perspective view of the heat exchanger of Embodiment 2. It is sectional drawing which shows the other example of the heat exchanger of Embodiment 2. FIG. FIG. 6 is a perspective view of a heat exchanger according to Embodiment 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Air flow path 2 ... Hydrogen flow path 3 ... Refrigerant flow path 4 ... Air duct 5 ... Chemical filter 6 ... Compressor 7 ... Silencer 8 ... Heat exchanger 9 ... Fuel cell stack 10 ... Radiator 13 ... Radiator fan 14 ... Intake side Manifold part 15 ... Heat exchanger body 16 ... Exhaust side manifold part

Claims (10)

A heat exchanger for a fuel cell vehicle, which is disposed in a place where an air flow is generated and adjusts the temperature of air supplied to the fuel cell stack to an appropriate temperature,
A fuel cell vehicle characterized in that the thickness of the portion that is exposed to air and the portion that is not exposed to air are changed, and the thickness of the portion that is exposed to air is made thinner than the thickness of the portion that is not exposed to air. Heat exchanger. A heat exchanger for a fuel cell vehicle according to claim 1,
The means for generating the air flow is a radiator fan. A heat exchanger for a fuel cell vehicle. A heat exchanger for a fuel cell vehicle according to claim 1,
The heat exchanger for a fuel cell vehicle, characterized in that the means for generating the air flow is traveling by a vehicle. A heat exchanger for a fuel cell vehicle according to any one of claims 1 to 3, comprising:
The part which the air hits is a part where the surface temperature of the heat exchanger having a surface temperature distribution becomes high. A heat exchanger for a fuel cell vehicle. A heat exchanger for a fuel cell vehicle according to any one of claims 1 to 3, comprising:
The heat exchanger for a fuel cell vehicle, characterized in that the portions where the air hits are a heat exchanger main body, an air supply side manifold portion, and an exhaust side manifold portion. A heat exchanger for a fuel cell vehicle according to any one of claims 1 to 5, comprising:
A heat exchanger for a fuel cell vehicle, characterized in that a portion facing toward the passenger compartment when mounted on a vehicle is thicker than other portions. A heat exchanger for a fuel cell vehicle according to claim 5,
A heat exchanger for a fuel cell vehicle characterized in that the center position of the pipe inner diameter and the pipe outer diameter of the intake manifold section and the exhaust manifold section is decentered to change the thickness. A heat exchanger for a fuel cell vehicle according to claim 5,
A heat exchanger for a fuel cell vehicle, characterized in that the intake side manifold portion is arranged forward in the vehicle traveling direction. A heat exchanger for a fuel cell vehicle according to claim 8,
A heat exchanger for a fuel cell vehicle, characterized in that a thickness of the intake side manifold portion is at least thinner than a thickness of the exhaust side manifold portion. A heat exchanger for a fuel cell vehicle according to any one of claims 5 to 9, comprising:
A heat exchanger for a fuel cell vehicle, characterized in that the intake side manifold portion is disposed toward the rear of the radiator fan.

Images