Answer :
Final answer:
The refrigerant charge in a capillary tube system, critical for its operation, is known as a fixed or critical charge. This charge affects the system's overall performance and is tied to the efficiency measure referred to as the Coefficient of Performance (COP).
Explanation:
The refrigerant charge on a capillary tube system is referred to as a fixed charge or a critical charge, meaning a precise quantity of refrigerant that must be added to the system for optimal performance. Too much or too little refrigerant can lead to inefficiencies or system failure.
The vapor compression refrigeration system operates on a closed cycle, with the refrigerant undergoing phase changes to absorb and release heat, thus enabling cooling. The Coefficient of Performance (COP) is a measure of the system's efficiency, indicating the ratio of cooling provided to the energy expended. The role of the capillary tube in these systems is to assist in the throttling process, where it controls the flow of refrigerant from high-pressure to low-pressure regions, facilitating its evaporation in the evaporator. It's essential to understand that in such systems, the capillary action is related to the movement of fluids through the capillary tube based on surface tension and not directly to the refrigerant charge.
