Define heat exchanger. Classify heat exchangers based on geometry, direction of fluids, method of heat exchange.

Define heat exchanger. Classify heat exchangers based on geometry, direction of fluids, method of heat exchange.
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1 Answer

Answer :

1. A heat exchanger is a device, which transfers thermal energy between two fluids at different temperatures.

2. In most common engineering applications, both fluids are in motion and the main mode of transferring heat is convection.

Heat exchanger can be classified based on:

1. According to the geometry:

i. Tubular

ii. Plate

iii. Plate fin

iv. Tube fin

2. According to the direction of fluid:

i. Parallel flow

ii. Counter flow

iii. Cross flow

3.According to the method of heat exchange:

i. Single phased free or forced convection

ii. Boiling or condensation

iii. Radiation or combined convection radiation
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