GB2290063A

GB2290063A - Low-drag vehicle radiator arrangement

Info

Publication number: GB2290063A
Application number: GB9410913A
Authority: GB
Inventors: Russell Pearce Gould
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-06-01
Filing date: 1994-06-01
Publication date: 1995-12-13
Also published as: GB9410913D0

Abstract

A high-speed vehicle has its drag reduced by mounting at least one air-cooled radiator 14 in a surface which is largely parallel to the airflow when the vehicle is in motion. The vehicle may be fitted with a pair of aerofoils 10 projecting sideways between the wheels and applying a downwards force, and the radiators may be in the upper surfaces so that they have air supplied to them under positive pressure. The downstream face of each radiator is preferably in communication with the rear of the body of the vehicle so that the sub-atmospheric pressure in its wake applies a pressure difference across it. <IMAGE>

Description

Vehicles This invention relates to vehicles, and particularly to cars intended to travel at high speeds, at which drag is important.

The temperatures of vehicle engines are intended to be kept within a relatively-narrow band once the engines have reached their working temperatures. Overheating is prevented by passing liquid coolant from the engine through a radiator in which the coolant dissipates heat to the atmosphere. Such radiators are usually positioned transversely to the airflow past the vehicle so that cooling air becomes 'rammed' into the radiator. Such flow of air is sometimes enhanced by a motor-driven fan which draws air through the radiator when the natural airflow is insufficient to cool the coolant sufficiently.

In racing cars in particular it is a considerable design constraint to use a front-facing radiator, because it slows and generally interferes with the flow of air through and past the car. This adds drag to the resistance of the car to forward motion, thus diverting engine power to the task of overcoming the radiator drag. In addition, the radiator is susceptible to damage from projectiles, such as pebbles thrown up by cars immediately in front.

The present invention ains at positioning the radiator on a vehicle in a position largely parallel to the airflow, so that it offers very little drag.

Accordingly, the present invention provides a road vehicle fitted with a radiator which is largely parallel to the direction of flow of air past the radiator when the vehicle is in motion, and hence presents only a low impedance to the airflow, in which vehicle the radiator is subjected to a pressure difference across it arising from the said airflow.

According to a further feature of the present invention, the superstructure of the vehicle has a pair of aerofoils projecting from opposite sides thereof at a location intermediate the front and rear wheels in plan, each aerofoil being designed to exert a downwards force on the vehicle as a function of the speed of the vehicle relative to the ambient air.

The present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a side view of a racing car fitted with aerofoils having horizontal radiators in them, and Figure 2 is a plan view of the car shown in Fig 1.

The car shown in the drawings has a fuselage 2 supporting front and rear wheels 4 and 6. Intermediate the wheels, and aligned with the cockpit 8, is a pair of aerofoils 10. As shown in Fig 2, these extend outwardly for about the width of the fuselage. Their longitudinal extent is such that they add appreciably to the stiffness of the fuselage, and hence give significant protection to the driver from side impact. The aerofoils have their undersurfaces more heavily clambered than their upper surfaces, and have such an angle of attack to the oncoming airflow that their undersurfaces are sucked towards the road surface 12, and their upper surfaces have downwards pressure applied by the airflow. The resultant force towards the road contributes significantly towards the stability of the car.

In accordance with the present invention, each aerofoil has in its upper surface a substantially-horizontal radiator 14. In communication with the lower face of each radiator is a chamber 16 which extends to the rear of the fuselage 2 and vents there into the wake of the vehicle. Immediately aft of the fuselage the wake of a moving vehicle is at sub-atmospheric pressure. This pressure is applied as suction to the undersurface of both radiators, thus contributing to the pressure difference across the radiator which induces the flow of cooling air through the radiator. The air leaving the radiator passes along chamber 16 and is discharged into the wake, leading to a reduction in the wake, and thus in the drag.

Because the radiator is virtually flush with the upper surface of the aerofoil, it contributes very little drag, other than that imparted by the flow of air through it, which is less than the airspeed of the car.

It will be appreciated that the radiator could be mounted vertically in a sidewall of the fuselage, with the same beneficial effect. In such a location there might be little or no positive pressure on the inlet face of the radiator, which entails arrangements being made for a significant subatmospheric pressure being applied to the downstream face of the radiator, by means internal of the vehicle which do not rely on the supply of additional energy.

It will be seen that the present invention provides a method of mounting an air-cooled radiator in a vehicle in such a manner as not to add significant amounts of drag.

Claims

Claim

1 A road vehicle fitted with a radiator which is largely parallel to the direction of flow of air past the vehicle when in motion, and hence presents only a low impendance to the airflow, in which vehicle the radiator is subjected to a pressure difference across it arising from the said airflow.

2 A vehicle as claimed in claim 1, in which the fuselage or superstructure of the vehicle has a pair of aerofoils projecting from opposite sides thereof at a location intermediate the front and rear wheels in plan, each aerofoil being designed to exert a downwards force on the vehicle as a function of the speed of the vehicle relative to the ambient air.

3 A vehicle as claimed in claim 2, in which the radiator is positioned in an upper surface of the aerofoil, and in which the downstream face of the radiator is in cormunication with a region of sub-atmospheric pressure.

4 A vehicle as claimed in claim 3, in which the downstream face of the radiator forms one boundary of a chamber which is communication with the rear of the vehicle fuselage.

Amendments to the claims have been filed as follows 1. An airfoil structure attached to a body, said airfoil incorporating an opening in the high pressure side through which ambient air is admitted and an exhaust duct connected to an area of low pressure associated with the forward movement of said body; said airfoil provided further with a heat exchanger positioned within itself and between said opening and said exhaust duct, across which heat exchanger air is caused to flow by said pressure differential.

2. An airofoil structure according to claim 1, attached horizontally to a motor vehicle for the purpose of providing down force, said heat exchanger serving to dissipate heat from the engine of said vehicle.

3. Twin airofoil structures as in claim 2, positioned between the front and rear wheels on either side of said motor vehicle, typically an open-wheeled racing car.

4. Twin airofoil structures as in claim 2. wherein said exhaust duct is connected to the air intake of sa 8 engine for the ancillary purpose of heating said intake air.

5. Twin airofoil structures as in claim 2, wherein said exhaust duct is connected to the area of low pressure in the wake of said vehicle.