How is the pressure ratio of a refrigeration compressor calculated?

The pressure ratio of a refrigeration compressor is calculated by dividing the absolute discharge pressure by the absolute inlet pressure. This ratio provides important information about the performance of the compressor.

The absolute pressures are used in this calculation because it ensures that the pressures are referenced from absolute zero, which is critical for accurate comparisons. Using absolute pressures helps eliminate discrepancies that may arise from atmospheric pressure fluctuations, which can occur if gauge pressures are used.

Calculating the pressure ratio correctly is vital for understanding the compressor's efficiency and performance, as it indicates how much the compressor can increase the refrigerant's pressure from the inlet to the discharge. This ratio is also crucial for thermodynamic analysis and assessment of the refrigeration cycle.

In summary, dividing the absolute discharge pressure by the absolute inlet pressure allows for a consistent and accurate measure of the compressor's performance in refrigeration systems.