3 c]What are the three modes of Heat transfer? Explain the process of Heat transfer in an Automobile radiator.
Heat Transfer:
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems.
Modes of Heat Transfer:
- Conduction Heat Transfer
- Convection Heat Transfer
- Radiation Heat Transfer
AUTOMOBILE RADIATORS:
“The radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating”
- Radiators are used to convert thermal energy from one mode to another for the purpose of cooling and heating.
- Radiators function in automobiles, buildings as well as in electronics.
- It acts as a coolant source for automotive engine cooling.
- Radiators transfer most of their heat via convection rather than thermal radiation.
- If there are large temperature differences, it can cause distortion of the engine components.
- The radiator will do the cooling purposes because the temperature of the burning gases in the engine cylinder reaches up to 1500 to 2000°C.
- If the heat is not dissipated there can be a failure of the cylinder material. Radiators can reduce the chances of piston seizure and keep the temperature minimum.
Radiator Main Parts or Construction:
Parts of Radiators
Below are the major parts of radiators and their functions:
a) Core:
The core is the major part of a radiator that serve its main purpose. It is a metal block with small metal fins which through it the coolant heat is a vent to the air surrounding the radiator. Cores are used to classified radiators, for instance, one-core, two-core, or even three- core radiators.
b) Pressure/Filler Cap:
As the coolant in the radiator is always under pressure, which helps to keep the coolant much hotter under without boiling. This allows the system to be much more efficient. The function of the pressure cap is to bleed off the hot coolant since it rises at some point. The hot coolant could cause damage to the coolant parts if the pressurize cap not functioning well.
c) Outlet and Inlet tank:
The outlet and the inlet portion of the radiator are where the flows in and out of the radiator. It’s located in the radiator head which is made of metal or plastic. From the engine, hot coolant flows through the inlet portion to radiator and from the outer portion to the engine. The hose is used to make the connections.
d) Cooler:
Some cars use the same cooler as the engine transmission cooler. In the transmission system, the fluid passes through a steel pipe to ensure the coolant circulation. This coolant is also cooled within the radiator because heat is also generated through an automatic transmission. Although some engines are designed with separate radiator for the transmission