What effect does clearance volume have on a compressor?

Clearance volume is a critical design factor in a compressor that significantly affects its capacity. The clearance volume is the space in the compressor cylinder that is not swept by the piston during its stroke. When this volume is present, not all of the air or gas drawn into the cylinder can be compressed. The existence of clearance volume means that, during the compression cycle, a portion of the gas remains at higher pressure and is not fully compressed, leading to the phenomenon known as "loss of capacity."

When clearance volume is larger, it reduces the effective displacement of the compressor, thus decreasing its overall capacity since some of the volume is effectively wasted. This aspect is crucial for engineers to consider when designing or selecting a compressor, as it directly influences the amount of gas that can be moved and the overall efficiency of the system. Adjustments to the clearance volume can be made to optimize performance for specific applications, balancing factors such as efficiency and capacity needs.

Factors such as efficiency, noise, and lubrication may be affected by other design aspects or operating conditions but are not directly influenced by clearance volume in the same way that compressor capacity is.