Refrigeration & Equipment Engineering

3.2.1.1.Bare tube, Plate and Finned evaporator

Unit 3 - Parts of refrigeration systems

Bare tube evaporator
In this type of evaporator the entire surface of the coil is in contact with the refrigerant inside. This type of evaporator is also called prime-surface evaporator. The bare tube coil evaporators are extensively used in household refrigerators because they are easier to keep clean. The material used for bare tube evaporator is steel or copper.

Plate evaporator
In this type of evaporator, the coils are either welded on one side of a plate or between the two plates which are welded together at the edges. The plate evaporators are generally used in house hold refrigerators, home freezers, beverage coolers, ice cream cabinets etc.

Finned Evaporators
In this type of evaporator the outer surface area is surrounded by thin metallic plates called fins. Fins are thin metallic plates, usually aluminum or copper, securely attached or banded to the evaporator tubes, with bare tube evaporators. These fins increase the heat transfer efficiency of the evaporator. Finned evaporators are used in air cooling application.