Heat and Thermodynamics

7.14 Refrigerating Mechanism

It is the mechanism of artificially maintaining a reservoir at a fixed desired temperature lower than that of the surrounding which is done by extracting heat from a cold reservoir with as little work as possible, applied externally. If a device takes heat Q₂ from cold body at temperature T₂ and gives out heat Q₁ to the surrounding or hot body at temperature T₁, the excess of heat Q₁ over Q₂ is the work W applied on the device, then the coefficient of performance is defined as

 

 

At temperatures above 10°C, bacteria increase greatly at a rapid rate. Food materials such as cooked food or raw materials such as fish, ...