In which system would you expect to find a surge drum?

A surge drum is primarily used in flooded systems, where it serves a critical function in managing the flow of refrigerant. In a flooded system, the evaporator is kept full of liquid refrigerant, which allows for efficient heat exchange as the liquid refrigerant absorbs heat and then evaporates. The surge drum acts as a reservoir that ensures a consistent supply of liquid refrigerant to the evaporator. It helps to accommodate variations in refrigerant flow and pressure while preventing liquid from sloshing back into the compressor.

Additionally, the surge drum plays a role in separating gas from liquid refrigerant, ensuring that only vapor enters the compressor. This helps protect the compressor from liquid slugging, which can cause significant damage. The inclusion of a surge drum in a flooded system thus contributes to the efficiency and reliability of the cooling process, making it a vital component in such systems.

In contrast, dry expansion systems do not usually utilize surge drums since they rely on a different refrigerant flow process that does not require the same level of liquid management. Closed loop and open loop systems also differ in their design and functionality, typically not incorporating surge drums in the same manner as flooded systems do.