What is a Heat Exchanger?

Author: Kr Shelar

What is a Heat Exchanger?

It is a specially engineered device, permitting the transfer of heat (energy), from one fluid to another fluid, without the two fluids mixing in reality.

Simply, it means that the exchanger transfers only the heat and not the fluid that carries it.

The fluid medium may be a liquid or gas. Sometimes a solid wall, a metal separator, separates the two fluids, restricting them from mixing.

Flow arrangement in a Heat Exchanger

Commonly, they are classified based on their flow arrangement. These exchangers are divided into three primary categories, namely parallel, counter and cross – flow.

  1. In Parallel flow arrangement, the fluids (either liquids or moving gases) enter the exchanger from one end, moving parallel together to meet the other end.
  2. If the Counter – flow arrangement, the fluids enter the exchanger from the opposite ends.
  3. The fluids in the Cross – flow exchanger flow in a perpendicular pattern to each other.

If the three arrangements, the Counter - flow arrangement proves to be the most efficient, transporting maximum amount of heat from the fluid medium. Parallel arrangement of fluid allows uniform wall temperatures.

How does a heat exchanger work?

A heat exchanger functions to retrieve warm air from waste, deplete gases and liquids, to transfer it directly to a different medium, for reuse.

In the air to air heat exchanger, the humidity of the dirty air from your house travels to the heat exchanger, to be transferred to the incoming fresh air. Ducts, solid separators inside the device separate the incoming and outgoing air.

It is through this air – duct system that the dirty air is replaced by the same amount of fresh outside air that enters your home. Due to the existence of many ducts inside the device, the fresh air does not mix with the dirty air, though they cross the same path.

As a result, the heat of the warm air leaving your house meets the cold outside air entering inside.

Thus, heat exchangers serve a great purpose to all our needs. They are the most versatile devices, available in plenty of shapes, sizes, dimensions, colors, materials, etc.

To know more about heat exchangers visit http://www.einfraproject.com/