Answer :
The main form of heat transfer in a car radiator is (d) Forced convection.
In a car radiator, the heat from the engine coolant is primarily transferred to the air through the process of forced convection. Here’s how it works:
Engine Coolant Circulation: The engine generates heat while running. To prevent overheating, a coolant circulates through the engine, absorbing this heat.
Radiator Function: The heated coolant then flows into the radiator, a key component of the car's cooling system. The radiator consists of thin metal fins and tubes where the coolant passes through.
Airflow and Heat Transfer: As the car moves or the radiator fan operates, cool air is forced through the radiator. This airflow helps dissipate heat from the coolant to the outside air, cooling the coolant in the process. This is termed 'forced convection' because the air movement is not natural (or free) but assisted by the fan or the vehicle's motion.
Cooling and Recirculation: Once the coolant is cooled down, it recirculates back into the engine to absorb more heat, maintaining the engine at an optimal temperature.
This method of heat transfer is crucial in maintaining the engine's temperature and ensuring efficient operation. Forced convection is particularly effective because the movement of the air (either from the vehicle moving or the fan) enhances the heat exchange rate compared to natural convection.
