What happens to the volumetric efficiency of a compressor when the horsepower decreases?

When the horsepower of a compressor decreases, the volumetric efficiency tends to increase. Volumetric efficiency is defined as the ratio of the actual volume of refrigerant vapor drawn into the compressor to the theoretical volume that could be drawn in at the same conditions.

A decrease in horsepower means that the compressor is working at a lower power level, which can result in a lower compression ratio and less energy loss due to heat and friction. This reduction in power often allows the compressor to operate more effectively, enabling it to draw in a greater volume of refrigerant vapor relative to its capacity. Thus, with an optimal balance between the power applied and the amount of refrigerant being compressed, the volumetric efficiency can improve.

Understanding this relationship is crucial for optimizing compressors in refrigeration systems. A higher volumetric efficiency indicates that the compressor is more effective at drawing in and compressing refrigerant, which can lead to more efficient system performance.