Working Principles of Heat Exchanger
Heat exchanger functions by transferring heat from higher to lower temperatures. Heat can thus be transferred from the hot fluid to the cold fluid if a hot fluid and a cold fluid are separated by a heat-conducting surface.
The operation of a heat exchanger is governed by thermodynamics. Heat can be transferred with the help of conduction, convection, or radiation. Conduction is the transfer of thermal energy from one material to another through the motion of a fluid such as heated air or water.
Convection is the transfer of thermal energy from one surface to another through the motion of a fluid such as heated air or water, and thermal radiation is a heat energy transfer mechanism characterized by the emission of electromagnetic waves from a heated surface or object.
The laws of thermodynamics are the fundamental concepts that underpin heat exchangers. The Zeroth Law of Thermodynamics states that in thermal equilibrium, thermodynamic systems have the same temperature. If two systems are in thermal equilibrium with a third system, the two former systems must also be in thermal equilibrium with one another; hence, all three systems are
- at the same temperature.
- The First Law of Thermodynamics states that energy cannot be created or destroyed, but it can be transmitted from one medium to another, such as heat.
The Second Law of Thermodynamics establishes entropy (S) as an additional property of thermodynamic systems, which describes a closed thermodynamic system’s natural invariable tendency to increase in entropy over time