The heating furnace, water boiler, car radiator or the air conditioner all work on the principle of thermal heat exchange between fluids. Heat exchange takes place between two fluids of varying temperature. If a fluid is to be heated then it is made to pick the heat from the other hotter fluid making the other fluid lose its temperature. When a hot fluid is to be cooled it is made to pass its heat to the other fluid which is cold, effectively raising the temperature of the other fluid. So here thermal heat exchange has taken place between fluids with each of them either losing or gaining temperature.

The device inside which this heat transfer takes place between the fluids is called a heat exchanger. The shell-tube heat exchangers and flat plate heat exchangers are the most widely used and popular among the surface heat exchangers wherein the two fluids do not have direct contact with each other and are separated by a solid surface divider made of good conducting material. Go in for the best quality heat exchanger so that it is durable, efficient and lasts longer. Heat exchangers are available online at www.aicheatexchangers.com and can be purchased as per requirement.

Shell and tube heat exchanger:

It encompasses a shell inside which a tube bundle is housed. The fluid which is to be heated or cooled is passed inside the tube and it travels through the length of the tube. The other fluid with a varied starting temperature is within the shell and passes above the tube. Thus heat transfer takes place between the fluid inside the tube and the fluid flowing on the outside of the tube.

Flat plate heat exchanger:

Here the two fluids are made to pass through the gaps between a stack of conducting plates which acts as a divider. Each of the fluids is made to fill alternative gaps using a gasket system or by brazing thus enabling heat exchange through consecutive plates separated by fluids of varying temperature.

Advantages and limitations of shell-tube heat exchanger and flat plate heat exchanger:

• The plate exchanger cost is higher than the tube exchanger, but is more efficient since the surface contact area in a plate is more when compared to that in a tube.
• The tube type consumes more space whereas the brazed plate heat exchangers are compact and easy on maintenance.
• The shell and tube heat exchanger can withstand higher pressure and temperature and there is less pressure drop.
• The shell and tube heat exchanger is easily repairable because any leak in the tube is easily traceable.
• The capacity of heat transfer load can be lowered or raised by altering the pair of plates in a gasket flat plate heat exchanger.
• The maintenance of plate heat exchanger is simple and the damaged or leaking plates can be easily replaced and no extra space is needed during repair whereas in shell and tube heat exchanger extra space is required when the tube bundle is to be pulled out from its shell in one end.

So what type of heat exchanger is required is based on the functionality and its advantages and limitations.