Abstract
On the test rig, the heat performance of engine cooling module composed by a radiator, an A/C condenser and an electric fan is largely different compared to the heat performance on the vehicle. In the test rig, the air flow distribution through the cooling module is uniform. On the other hand on the vehicle, this air flow distribution is completely different and influenced by the front end of vehicle and the engine compartment like: grill, air inlet cross section, bumper position, ram air, pressure coefficient at the front end and at the air outlet of under-hood and vehicle speed...
For each vehicle, the cooling radiator and the A/C condenser liquid flow rate can be easily measured by the liquid flow meter but the actual air flow rate across the cooling radiator and A/C condenser become a serious problem due to the influence of different components listed above.
Two main parameters will be shown concerning the engine cooling module: the average air velocity through the A/C condenser and their heat performance versus the vehicle speed.
The engine cooling module performance will be studied and presented, particularly:
- The influence of the cooling radiator ( geometry and performance),
- The influence of size and position of A/C versus the cooling radiator,
- The influence of the electric fan ( size, power and performance, fan on or fan off),
- The influence of fan shroud ( without fan shroud, with full fan shroud or with partial fan shroud),
- The influence of vehicle (pressure coefficient, grill, size of air inlet, under-hood, size of under-hood air outlet and etc).
Several vehicles were equipped with different sensors and tested in the climatic wind tunnel according to the engine cooling specifications. These test results have been compared to the calculation results obtained by our own simulation model.