JP2020175680A - Fan shroud for heat exchanger installed on vehicle - Google Patents

Abstract

To supply ambient air to a heat exchanger efficiently while restraining hot air from a power unit chamber side from being gone around a heat exchanger in a fan shroud for the heat exchanger installed on a vehicle.SOLUTION: A fan shroud is a fan shroud which leads ambient air passing through a heat exchanger installed on a vehicle to a fan. It is provided with a ram pressure hole on the outside of a vehicle width direction in a back wall of the fan shroud. In addition, an inclination wall part of which inclination angle is set is provided on the back wall of the fan shroud so that wind passing through the ram pressure hole faces a wheel house side which is in the outside of the vehicle width direction.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to fan shrouds for heat exchangers mounted on vehicles.

A condenser or radiator is used as a heat exchanger for cooling a power unit such as a vehicle engine, and a fan for forcibly supplying outside air is provided to these. The fan is arranged between the heat exchanger and the power unit, and is configured to suck in outside air through the heat exchanger and discharge it to the power unit chamber. With this configuration, it is possible to secure the amount of air passing through the heat exchanger even when the vehicle is stopped or traveling at a low speed. In addition, by providing a fan shroud that guides the outside air that has been heat-exchanged by the heat exchanger to the fan so as to surround the entire circumference of the heat exchanger except for the fan opening, the cooling efficiency by the fan is improved and the inside of the power unit room. It is possible to prevent hot air from flowing back to the heat exchanger side.

On the other hand, while the vehicle is traveling, ram pressure, which is a pressure opposite to the traveling direction received from the traveling wind, is generated on the upstream side of the heat exchanger, so that the outside air flows into the heat exchanger. In this case, since the fan shroud has no opening other than the fan opening, the fan shroud acts as a flow path resistance against the inflow air. Therefore, the amount of air discharged from the fan opening is suppressed, and the efficiency of recovering the ram pressure is lowered.

Therefore, in a vehicle provided with the vehicle heat exchange module of Patent Document 1, discharge ports are provided on all four sides of the fan opening of the fan shroud on the outer peripheral side, and a large amount of air is discharged from the four discharge ports to the power unit chamber side. Is disclosed.

Reference 2 states that if a fan shroud is provided with an outlet, hot air in the power unit chamber wraps around to the heat exchanger side through the outlet when the ram pressure is low, such as when the vehicle is idling or running at low speed. I'm pointing out. Therefore, it is disclosed that a vent is provided on one side surface of the fan of the fan shroud, and a partition wall in which the back surface of the fan shroud is extended is formed at the edge of the vent. The partition wall has a surface parallel to the back surface of the fan shroud and a bent portion bent toward the power unit chamber side away from the back surface of the fan shroud.

As a technique related to the present disclosure, in Patent Document 3, a plurality of ventilation holes are provided in the side members extending in the front-rear direction of the vehicle along the side wall of the power unit chamber, and the wind passing through the fan is blown to the left and right through the ventilation holes. It is stated that it will lead to a wheel house.

JP-A-2010-132182 Japanese Unexamined Patent Publication No. 2001-132453 Japanese Unexamined Patent Publication No. 10-159565

The wind discharged into the power unit chamber from the discharge port such as the fan opening or the ram pressure hole of the fan shroud is discharged to the outside of the vehicle through the gap in the power unit chamber. In the case of a vehicle equipped with an engine, the wind is discharged under the floor from a gap near the engine exhaust pipe, and in the case of an electric vehicle or the like without an engine, the wind is discharged to the outside of the vehicle through a gap near the wheel house.

If the wind does not flow smoothly to the outside of the vehicle in the power unit room, the wind does not pass smoothly and the heat exchanger is not sufficiently supplied with outside air. In particular, the ram pressure hole or the like affects the way the wind flows in the power unit chamber depending on the arrangement position and the setting of the opening shape, etc., and thus affects the release of the wind to the outside of the vehicle. Therefore, there is a demand for a fan shroud for a heat exchanger mounted on a vehicle capable of efficiently supplying outside air to the heat exchanger while suppressing the hot air from the power unit chamber side from sneaking into the heat exchanger.

The fan shroud for the heat exchanger mounted on the vehicle according to the present disclosure is a fan shroud that guides the outside air passing through the heat exchanger mounted on the vehicle to the fan, and is in the vehicle width direction on the back wall of the fan shroud. An inclined wall provided on the outside and an inclined wall provided on the back wall of the fan shroud so that the wind passing through the ram indentation faces the wheel house side on the outside in the vehicle width direction. It has a part and.

According to the above configuration, a lamb pressure hole is provided on the outer side of the rear wall of the fan shroud in the vehicle width direction. An inclined wall portion is provided on the back wall of the fan shroud, and the inclination angle is set so that the wind passing through the ram impression hole faces the wheel house side. By providing the inclined wall portion, it is possible to prevent hot air from the power unit chamber side from sneaking into the heat exchanger. In addition, since the inclination angle is set so that the wind passing through the ram pressure hole faces the wheel house side, the wind passing through the ram pressure hole is smoothly discharged to the outside of the vehicle through the gap near the wheel house in the power unit chamber. And the wind is good. As a result, the outside air can be efficiently supplied to the heat exchanger.

According to the fan shroud for the heat exchanger mounted on the vehicle having the above configuration, the outside air is efficiently supplied to the heat exchanger while suppressing the hot air from the power unit chamber side from sneaking into the heat exchanger. Becomes possible.

It is a plane layout of the power unit room of the front structure of the vehicle in which the fan shroud for the heat exchanger mounted on the vehicle in the embodiment is arranged. It is a rear view which took out the fan and the fan shroud in FIG. 1 and looked at from the rear side of a vehicle. It is sectional drawing along the line III-III' of FIG. It is an enlarged view of the IV part of FIG. It is a figure explaining the position suitable for installation of a ram pressure hole. It is a figure which shows the velocity distribution of the wind in a fan shroud which does not have a ram impression hole. As a first conventional example having no ram indentation hole, it is a figure which shows the wind flow at the time of using a 1-fan type fan shroud in an engine-mounted vehicle. As a second conventional example having no ram pressure hole, it is a figure which shows the wind flow at the time of using a 2-fan type fan shroud in an engine-mounted vehicle. It is a figure which shows the flow of the wind in the IX part of FIG. It is a figure which shows the flow of the wind in part X of FIG. As a third conventional example having no ram hole, it is a figure which shows the wind flow at the time of using the 2 fan type fan shroud in the electric vehicle which does not have an engine. It is a figure which shows the distribution of the wind flow under the floor using the cross-sectional view of the vehicle in the 1st conventional example. It is a figure which shows the flow of the wind which flows from the front side to the rear side of a vehicle under the floor of the example of FIG. It is a figure which shows the distribution of the wind flow under the floor using the cross-sectional view of the vehicle in the 3rd conventional example. It is a figure which shows the flow of the wind which flows from the front side to the rear side of a vehicle under the floor of the example of FIG.

Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. In the following, one radiator and one capacitor will be described as heat exchangers, and it is assumed that outside air is supplied to both of them by a fan, but this is an example for explanation. The type and number of heat exchangers may differ depending on the specifications of the vehicle and the like. For example, the heat exchanger may be any one type of radiator or condenser, in which case the outside air is supplied to the one type of heat exchanger by a fan.

The shapes, materials, numbers, etc. described below are examples for explanation, and can be appropriately changed depending on the specifications of the fan shroud for the heat exchanger mounted on the vehicle. In the following, a case where a pair of ram pressure holes are provided on both ends in the width direction of the fan shroud will be described, but this is an example for explanation and depends on the specifications of the fan shroud for the heat exchanger mounted on the vehicle. Therefore, the placement location and the number can be changed as appropriate. For example, one ram pressure hole may be provided outside the width direction of the fan shroud. Further, in the following, the same elements are designated by the same reference numerals in all the drawings, and duplicate description will be omitted.

FIG. 1 is a plan layout of each element of the power unit chamber 14 on the front side of the vehicle compartment 12 in the vehicle 10. The power unit chamber 14 is a space in which the power unit 16 is arranged. The power unit 16 is an engine and related devices when the vehicle 10 is equipped with an engine, and the power unit chamber 14 is called an engine chamber. When the vehicle 10 is an electric vehicle not equipped with an engine, the rotating electric machine for driving and its related device are the power unit 16.

In each of the following figures, the vehicle front-rear direction, the vehicle vertical direction, and the vehicle width direction are shown. Regarding the vehicle front-rear direction, the direction indicated by FR is the direction on the front side of the vehicle, and the direction indicated by RR is the direction on the rear side of the vehicle. Regarding the vehicle vertical direction, the direction indicated as UP is the direction on the upper side of the vehicle above the road surface, and the opposite direction is the direction on the lower side of the vehicle, which is the direction toward the road surface. Regarding the vehicle width direction, the direction indicated by RH is the direction on the right side of the vehicle, and the direction indicated by LH is the direction indicated on the left side of the vehicle. The right side and left side of the vehicle face the front side of the vehicle, the right side is the right side of the vehicle, and the left side is the left side of the vehicle. Since each member provided in the vehicle is often arranged symmetrically with respect to the center line along the front-rear direction of the vehicle, the width direction of the vehicle is inside the vehicle regardless of whether it is on the right side or the left side of the vehicle. The direction is called IN, and the direction outside the vehicle is called OUT.

The front grill 20 is a grid-like component arranged in front of the vehicle 10 on the front side of the power unit chamber 14, and serves as an outside air intake port for taking in the outside air 70 outside the vehicle to the power unit chamber 14 side. The wheel houses 22 and 24 are spaces provided on the outside in the vehicle width direction. Specifically, it is a space provided on the left and right OUT sides of the power unit chamber 14, and where the left and right front wheels 26 and 28 are arranged. The wheel houses 22 and 24 are not completely spatially separated from the power unit chamber 14, and are located between the power unit chamber 14 and the wheel houses 22 and 24 in order to extend the axles of the front wheels 26 and 28. Has gaps 23 and 25.

Since the power unit 16 generates heat due to its operation, a refrigerant such as cooling water is used. The heat exchanger 18 is a device arranged on the rear side of the front grill 20 and exchanges heat of the refrigerant from the power unit 16 with the outside air 70 to dissipate the heat to the outside, and returns the cooled refrigerant to the power unit 16 again. .. As the heat exchanger 18, a condenser and a radiator are used. The condenser is a condenser that constitutes a refrigerating cycle for an air conditioner in a passenger compartment, and the radiator is a radiator that circulates a refrigerant for cooling the power unit 16.

The fan unit 30 is arranged on the vehicle rear side of the heat exchanger 18 and includes an electric fan. By driving the fan unit 30, the outside air 70 is sucked from the front grill 20 side to the power unit chamber 14 side via the heat exchanger 18, and the hot wind 72 that is heat exchanged by the heat exchanger 18 flows to the power unit 16 side. .. Ram pressure holes 60 and 62 that open diagonally to the rear of the vehicle are provided on the left and right OUT side surfaces of the fan unit 30. The winds 74 and 76 that have passed through the ram pressure holes 60 and 62 flow in the power unit chamber 14 toward the wheelhouses 22 and 24, and are outside the vehicle from the gaps 23 and 25 between the power unit chamber 14 and the wheelhouses 22 and 24. Is released to.

The fan unit 30 and the ram pressure holes 60 and 62 will be described in detail with reference to FIGS. 2 to 4. FIG. 2 is a rear view of the fan unit 30 in FIG. 1 taken out and viewed from the rear side of the vehicle. FIG. 3 is a cross-sectional view taken along the line III-III'of FIG. FIG. 4 is an enlarged view of the IV portion of FIG. 3, which is a detailed view of the ram pressure hole 60. 3 and 4 are flipped horizontally with respect to FIG. 2 in order to be consistent with FIG. On paper, FIG. 2 shows that the left side is the vehicle left side (III side) and the right side is the vehicle right side (III'side), but in FIGS. 3 and 4, the right side is the vehicle left side (III side) and the left side is the vehicle left side. It is on the right side of the vehicle (III'side).

The fan unit 30 includes a fan 32 and a fan shroud 40. The fan 32 is an electric fan including a plurality of blades 36 whose roots are fixed to a boss 35 provided on the rotating shaft 34 and extending radially outward, and an electric motor 38 for driving the rotating shaft 34. The fan shroud 40 is a frame that surrounds the entire circumference of the heat exchanger 18 so as to guide the outside air 70 that has passed through the heat exchanger 18 to the fan 32.

The fan shroud 40 includes an outer peripheral wall portion 42, a back wall portion 44, a bell mouth 46, and a plurality of strut portions 50. The back wall portion 44 is the bottom plate portion of the fan shroud 40, which is a frame body, and becomes the back wall on the rear side of the heat exchanger 18 when the fan unit 30 is arranged in the vehicle 10.

The back wall portion 44 is a flat plate member having a rectangular shape forming the bottom surface of the frame body, and the four-sided wall rising from the four sides of the rectangular shape is the outer peripheral wall portion 42. The outer peripheral wall portion 42 is attached to the heat exchanger 18 at an end portion opposite to the back wall portion 44 side. A circular fan opening 48 is provided in the central portion of the back wall portion 44, and a cylindrical bell mouth 46 is attached to the inner peripheral side of the fan opening 48. The strut portion 50 is a plurality of columnar members whose one end is fixed to the bell mouth 46 and the other end is fixed to the housing of the electric motor 38 of the fan 32.

According to the fan shroud 40 having the above configuration, the heat exchanger 18 is integrated with the outer peripheral wall portion 42, and the electric motor 38 of the fan 32 is held at the center of the fan opening 48 by a plurality of support columns 50. Therefore, the fan shroud 40 sucks the outside air 70 flowing from the front grill 20 of the vehicle 10 with the fan 32, exchanges heat with the heat exchanger 18, and guides the hot wind 72 with the outer peripheral wall portion 42 and the back wall portion 44. It works to lead to the fan 32. The wind 72 is discharged from the fan opening 48 to the power unit chamber 14 side by the blades 36 driven by the electric motor 38.

The fan shroud 40 is made of resin obtained by molding a resin into a predetermined shape. The strength can be increased by adding glass fiber to the resin. In some cases, instead of this, a steel plate press-formed into a predetermined shape may be used.

While the vehicle 10 is traveling, a ram pressure, which is a pressure opposite to the traveling direction received from the traveling wind, is generated, and the outside air 70 flows into the heat exchanger 18 due to the ram pressure. In the fan shroud 40 arranged on the rear side of the heat exchanger 18, the back wall portion 44 is a wind guide wall that guides the inflow air to the fan opening 48, so that it becomes a flow path resistance against the inflow air and discharges from the fan opening 48. The air volume is suppressed and the recovery efficiency of the ram pressure is reduced. The ram pressure holes 60 and 62 are provided to improve the ram pressure recovery efficiency in the fan unit 30.

The ram pressure holes 60 and 62 are provided at both outer ends of the fan shroud 40 in the rear wall portion 44 in the vehicle width direction. Specifically, it is provided at both ends on the outside of the vehicle and on the rear side of the vehicle. Since the ram pressure holes 60 and 62 are arranged symmetrically with respect to the rotation shaft 34 in the fan unit 30 and have the same configuration, the ram pressure holes 60 will be described below.

As shown in FIGS. 1 and 4, the ram pressure hole 60 is an elongated hole extending in the vertical direction of the vehicle and opening toward the rear side of the vehicle at the OUT side end of the back wall portion 44. The wind 73 that has passed through the OUT side of the heat exchanger 18 does not go toward the fan opening 48 on the IN side along the back wall portion 44 having a large flow path resistance, but opens to the back wall portion 44 to flow through the flow path. Head toward the ram pressure hole 60, which has less resistance.

The method of forming the ram pressure hole 60 is as follows. A vertical cut line 52 extending in the vertical direction of the vehicle at the OUT side end of the back wall portion 44, an upper cut line 54 extending from the upper end of the vertical cut line 52 to the IN side, and a vertical cut line 52. The inclined wall portion 58 is lifted at a predetermined inclination angle θ by using the lower cut line 56 extending from the lower end portion of the above to the IN side. The gap between the IN side end 53 of the back wall portion 44 corresponding to the vertical cut line 52 and the OUT side end 59 of the inclined wall portion 58 is the ram pressure hole 60. The ram pressure hole 62 can also be formed in the same manner.

At the OUT side end of the fan shroud 40 provided with the ram pressure hole 60, the wind 73 passing through the heat exchanger 18 does not flow straight in the front-rear direction of the vehicle, but an inclined surface having an inclination angle θ of the inclined wall portion 58. Guided by, it flows inclined to the OUT side on the rear side of the vehicle 10. Then, it is discharged to the power unit chamber 14 side from the ram pressure hole 60, which is a gap between the OUT side end portion 59 of the inclined wall portion 58 and the IN side end portion 53 of the ram pressure hole 60. The same applies to the ram pressure hole 62.

The predetermined inclination angle θ is set so that the wind 74 passing through the ram pressure hole 60 faces the wheel house 22 side. The predetermined inclination angle θ can be determined by simulation or experiment based on the arrangement relationship of the heat exchanger 18 in the power unit chamber 14 of the vehicle 10, the fan unit 30, and the gap 23 in the wheel house 22, and the traveling conditions of the vehicle 10. it can.

In FIG. 4, the difference between the position of the IN side end 53 of the back wall portion 44 and the position of the OUT side end 59 of the inclined wall portion 58 measured along the vehicle width direction is shown as the separation distance S. As described above, in the case of the method of making a cut in the vertical cut line 52, the upper cut line 54, and the lower cut line 56 and lifting the inclined wall portion 58 at a predetermined inclination angle θ, the separation distance S is the upper cut. It is uniquely determined by the length and inclination angle θ of the drop line 54 and the lower cut line 56. Instead of this, if necessary, the OUT side end portion 59 may be deleted to the IN side so as to reduce the size of the inclined wall portion 58, and a predetermined separation distance S may be obtained. The predetermined separation distance S can be determined by simulation or experiment in combination with the predetermined inclination angle θ. Similarly, for the ram pressure hole 62, the predetermined inclination angle θ and the predetermined separation distance S can be determined by simulation or experiment so that the wind 76 passing through the ram pressure hole 62 faces the wheel house 24. ..

To give an example of a predetermined inclination angle θ and a predetermined separation distance S, the length of the inclined wall portion 58 in the vehicle width direction is about 50 mm to 60 mm, and θ = about 30 degrees and S = about 10 mm. This is an example for explanation, and the setting is appropriately changed according to the arrangement relationship of each element in the power unit chamber 14 of the vehicle 10 and the traveling conditions of the vehicle 10.

The action and effect of the fan shroud 40 for the heat exchanger 18 mounted on the vehicle 10 having the above configuration will be described in more detail with reference to FIG. 5 and below.

FIG. 5 is a schematic view illustrating a position suitable for installing a ram pressure hole. In FIG. 5, the fan unit 80 used in the heat exchanger 18 includes a fan 82 and a fan shroud 84, and the fan shroud 84 is provided with a ram pressure hole 86. At the position where the ram pressure hole 86 is provided, the higher the pressure on the power unit chamber 14 side with respect to the pressure on the fan shroud 40 side, the hot air in the power unit chamber 14 wraps around to the fan shroud 84 side. Therefore, the position of the ram pressure hole 86 suitable for preventing the hot air of the power unit chamber 14 from wrapping around should be such that the pressure on the power unit chamber 14 side at that position is low. Generally, as shown in FIG. 5, the pressure in the power unit chamber 14 is high near the back of the fan 82 and lower as the distance from the fan 82 toward the OUT side. Since the positions of the ram pressure holes 60 and 62 described in FIGS. 2 to 4 are the positions of the OUT side ends farthest from the fan 32, the hot air in the power unit chamber 14 is suppressed from wrapping around. ..

FIG. 6 shows the fan 82 in the direction of the arrow in the fan shroud 88 having no ram pressure hole in order to explain the air volume effect by providing the ram pressure holes 60 and 62 at the OUT side end of the fan shroud 40. It is a figure which shows the velocity distribution of the wind when it is driven by rotation. The speed of densely shaded areas is faster than the speed of sparsely shaded areas. The white background is the place where the wind speed is the slowest. In FIG. 6, the position 83 of the cross mark (+) is the position of the rotation center of the rotation shaft 34 described in FIG. 3, and when the fan 82 rotates in the direction of the arrow, the flow velocity distribution is a point centered on the position 83. It has a symmetric distribution. The same applies when the rotation direction is opposite. The vicinity of position 83 is a part that is in the shadow of the electric motor 38 attached to the fan shroud 40, and the speed of the wraparound wind is not very high, but the flow velocity becomes high speed side from the outside to the outer peripheral side, and from position 83. The region having a radius to the frame in the vertical direction of the fan shroud 88 is the maximum speed region. Since the fan shroud 88 has a larger dimension in the width direction than a dimension in the vertical direction, the flow velocity drops sharply from the maximum speed region toward the outside in the width direction toward the end side. As described above, when there is no ram pressure hole, the wind speed is the lowest at the left and right OUT side ends of the fan shroud 88.

On the other hand, the positions of the ram pressure holes 60 and 62 described in FIGS. 2 to 4 are the left and right OUT side ends of the fan shroud 40, and the wind 73 is directed from the ram pressure holes 60 and 62 to the power unit chamber 14 side. Is discharged. As a result, the wind speed is improved at the left and right OUT side ends of the fan shroud 40, and the air volume of the wind 73 can be increased.

7 to 9 are views showing the flow of wind in a vehicle equipped with an engine when the wind passing through the heat exchanger 18 is discharged to the power unit chamber 14 only through the fan opening without providing the ram pressure hole. is there.

As a first example, the vehicle 90 of FIG. 7 includes an engine as a power unit 92 and has a tunnel portion 94 through which an engine exhaust pipe is passed. The fan unit 96 is a 1-fan type. The wind 98 discharged from the fan opening of the fan unit 96 flows toward the gap near the tunnel portion 94 having a small flow path resistance while bypassing a portion such as the power unit 92 where the flow path resistance becomes large. In the case of the one-fan type, the amount of wind component toward the gaps 23 and 25 near the wheel houses 22 and 24 is small as shown by a thinner arrow than the thick arrow of the wind 98.

As a second example, the vehicle 100 of FIG. 8 includes an engine as a power unit 102 and has a tunnel portion 104 through which an engine exhaust pipe is passed. The fan unit 106 is a two-fan type in which two fans are arranged side by side in the vehicle width direction. The wind 108 discharged from the fan opening of the fan unit 106 flows toward the gap near the tunnel portion 104 having a small flow path resistance while bypassing a portion such as the power unit 102 where the flow path resistance is large. In the case of the two-fan type, since the wind escapes from the end of the fan shroud, a part of the wind goes to the gaps 23 and 25 near the wheel houses 22 and 24.

In FIGS. 7 and 8, the wind flow around the OUT side of each of the fan units 96 and 106 differs depending on the difference between the 1-fan type and the 2-fan type. An enlarged view of the IX portion of FIG. 7 is shown in FIG. 9, and an enlarged view of the X portion of FIG. 8 is shown in FIG. Here, as the heat exchanger 18, it is shown that the condenser 17 is arranged on the front side of the vehicle and the radiator 19 is arranged on the rear side thereof. In FIG. 9 of the 1-fan type, since the fan shroud has no opening, the air at the end of the heat exchanger 18 does not easily escape. On the other hand, in FIG. 10 of the two-fan type, since the range covered by the fan openings of the two fans along the vehicle width direction is wide, the wind 109 is on the OUT side on the right side of the vehicle of the heat exchanger 18. Passes through.

From the comparison of FIGS. 9 and 10, the 1-fan type, which has become mainstream in recent years as a fan unit for mounting on a vehicle having no ram pressure hole, is on the right side of the vehicle of the heat exchanger 18 as compared with the 2-fan type. On the OUT side, it can be seen that the air does not escape well from the fan opening.

On the other hand, the fan unit 30 described in FIGS. 2 to 4 is a one-fan type, but since the ram pressure holes 60 and 62 are arranged at the left and right OUT side ends of the fan shroud 40, the heat exchanger 18 Wind 73 passes on the OUT side on the right side of the vehicle. In this way, by providing the ram pressure holes 60 and 62 in the 1-fan type fan unit 30, the air vent on the OUT side of the heat exchanger 18 on the right side of the vehicle can be prevented as compared with the conventional 1-fan type fan unit 96. Can be improved.

FIG. 7 of the first example and FIG. 8 of the second example are vehicles 90 and 100 equipped with an engine, but the vehicle 110 of FIG. 11 of the third example is an electric vehicle not equipped with an engine.

The vehicle 110 does not include an engine, and the power unit 112 is a rotary electric machine and related equipment. The fan unit 116 is the same two-fan type as the fan unit 106 of FIG. 8, and does not have a ram pressure hole. Since the vehicle 110 does not have an engine exhaust pipe, a gap near the engine exhaust pipe is not provided, and the wind 118 discharged from the fan opening of the fan unit 116 is provided in the gaps 23 and 25 near the wheel houses 22 and 24. I will head. The wind 118 bypasses a portion such as the power unit 112 where the flow path resistance becomes large, and heads toward the gaps 23 and 25 near the wheel houses 22 and 24 along the barrier 13 that separates the vehicle interior 12 and the power unit chamber 14. Therefore, the flow path resistance from the fan opening toward the gaps 23 and 25 near the wheel houses 22 and 24 is large, and sufficient outside air 70 cannot be taken into the heat exchanger 18.

On the other hand, in the fan unit 30 described in FIGS. 2 to 4, ram pressure holes 60 and 62 are arranged at the left and right OUT side ends of the fan shroud 40. As shown in FIG. 1, the OUT-side end of the fan unit 30 on the right side of the vehicle and the wall of the wheel house 22 are close to each other, and no special equipment or the like is arranged between them. Therefore, the winds 74 and 76 passing through the ram pressure holes 60 and 62 go directly to the wheel houses 22 and 24 without detouring. After that, it flows to the rear side of the vehicle along the side walls of the wheel houses 22 and 24, and when it reaches the gaps 23 and 25, it is discharged to the outside of the vehicle as it is, so that the wind 74 and 76 are good, and the heat exchanger 18 The outside air 70 can be efficiently supplied. As described above, by using the fan shroud 40 having the ram pressure holes 60 and 62 described in FIGS. 2 to 4 for the heat exchanger 18 mounted on the electric vehicle, the heat exchanger 18 is compared with the prior art. The outside air 70 can be efficiently supplied to the vehicle.

As described above, the wind discharged from the fan opening of the fan shroud is discharged under the floor through a gap near the engine exhaust pipe in the case of an engine-equipped vehicle. Since the electric vehicle does not have an engine exhaust pipe, it is discharged to the outside of the vehicle through a gap near the wheel house. This difference causes a difference in the flow of underfloor wind according to the running of the vehicle. 12 and 13 are diagrams showing the underfloor wind flow in the vehicle 90 equipped with the engine of the first example, and FIGS. 14 and 15 are diagrams showing the underfloor wind flow in the vehicle 110 not equipped with the engine of the third example. It is a figure which shows. 12 and 14 are views showing the flow of wind in the rear cross section of the power unit chamber 14 in terms of flow velocity distribution. 13 and 15 are views showing the flow of wind under the floor as seen from the road surface side in terms of wind speed distribution. In FIG. 12, it is shown that the turbulence 120 is generated in the velocity distribution of the underfloor wind due to the emission of the wind from the gap 95 in the vicinity of the engine exhaust pipe. In FIG. 13, it can be seen that the flow velocity turbulence 120 is generated on the downstream side of the tire 107, and at the same time, the wind speed distribution is turbulent in response to the wind emission from the gap 95 in the vicinity of the engine exhaust pipe. .. On the other hand, in FIG. 14, since the engine exhaust pipe is not provided, the underfloor wind at the portion corresponding to the gap 95 in the vicinity of the engine exhaust pipe in FIG. 12 is not turbulent. Similarly, in FIG. 15, the phenomenon corresponding to the turbulence of the underfloor wind peculiar to FIG. 13 does not occur.

As described above, when the wind discharged from the fan opening of the fan shroud is discharged to the underfloor of the vehicle, the underfloor wind of the vehicle may be disturbed and the aerodynamic performance of the vehicle may be deteriorated. On the other hand, in the fan unit 30 described in FIGS. 2 to 4, ram pressure holes 60 and 62 are arranged at the left and right OUT side ends of the fan shroud 40, and the wind 74 and 76 pass through the ram pressure holes 60 and 62. Is discharged to the outside of the vehicle from the gaps 23 and 25 near the wheel houses 22 and 24. This also applies to a vehicle having an engine exhaust pipe. Therefore, by providing the ram pressure holes 60 and 62 in the fan unit 106 mounted on the vehicle 100 of the second example, the wind passing through the heat exchanger 18 is provided. However, the amount of air discharged from the gap near the engine exhaust pipe is reduced. As a result, the turbulence of the underfloor flow is suppressed, and it is expected that the aerodynamic performance of the vehicle will be improved.

According to the fan shroud 40 for the heat exchanger mounted on the vehicle having the above configuration, the outside air is efficiently referred to the heat exchanger 18 while suppressing the hot air from the power unit chamber 14 side from sneaking into the heat exchanger 18. It becomes possible to supply 70. Further, by applying it to a 1-fan type fan unit, it is possible to improve the ventilation near the OUT side end of the fan shroud. Further, by applying it to an electric vehicle not equipped with an engine, the amount of air discharged to the outside of the vehicle from the gaps 23 and 25 near the wheel houses 22 and 24 can be increased, so that the outside air 70 can be efficiently supplied to the heat exchanger 18. can do. Further, by applying it to a vehicle equipped with an engine, it is possible to reduce the amount of air discharged from a gap near the engine exhaust pipe, suppress turbulence of underfloor wind, and improve the aerodynamic performance of the vehicle.

10, 90, 100, 110 vehicles, 12 cabins, 13 barriers, 14 power unit compartments, 16, 92, 102, 112 power units, 17 capacitors, 18 heat exchangers, 19 radiators, 20 front grilles, 22, 24 wheel houses, 23,25 Gap, 26,28 Front wheels, 30,80,96,106,116 Fan units, 32,82 fans, 34 rotating shafts, 35 bosses, 36 blades, 38 electric motors, 40,84,88 fan shrouds, 42 Outer wall, 44 back wall, 46 bellmouth, 48 fan opening, 50 stanchions, 52 vertical cuts, 53 IN side ends, 54 upper cuts, 56 lower cuts, 58 sloping walls, 59 OUT side end, 60, 62, 86 ram pressure hole, 70 outside air, 72, 73, 74, 76, 98, 108, 109, 118 wind, 83 position, 94, 104 tunnel part, 95 near engine exhaust pipe Gap, 107 tires.

Claims (1)

A fan shroud that guides the outside air passing through the heat exchanger mounted on the vehicle to the fan.
A ram pressure hole provided on the outer side of the back wall of the fan shroud in the vehicle width direction,
An inclined wall portion provided on the back wall of the fan shroud and having an inclination angle set so that the wind passing through the ram pressure hole faces the wheel house side on the outside in the vehicle width direction.
A fan shroud for heat exchangers mounted on vehicles.

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