In a reciprocating compressor, what does the term swept volume refer to?

Swept volume in a reciprocating compressor refers specifically to the volume moved by the piston as it travels from the top dead center (TDC) to the bottom dead center (BDC). This volume is crucial for understanding the compressor's capacity to move refrigerant or gas, as it directly correlates to the amount of gas that can be compressed and displaced in one complete stroke of the piston.

When considering this definition, it's essential to recognize that the swept volume does not account for the total volume of the cylinder, which would include both the volume above the piston at TDC and the swept volume itself. Additionally, the total volume of gas at discharge and the volume lost to leakage are not components of the swept volume; instead, they relate to broader operational conditions and efficiencies of the compressor. Understanding the definition of swept volume helps in calculating the efficiency and performance of a reciprocating compressor in refrigerant applications.