What is the compressor pressure ratio?

What is the compressor pressure ratio?

• A. The difference between outlet and inlet pressures
• B. The ratio of turbine inlet temperature to compressor outlet temperature
• C. The ratio of outlet pressure to inlet pressure
• D. The sum of all stage pressures in the compressor

Answer: (C)

The compressor pressure ratio is defined as the outlet pressure divided by the inlet pressure. It’s a dimensionless value that shows how much the compressor increases the air pressure as it passes through. In practice, you measure the inlet pressure (P1) and the outlet pressure (P2) and compute CPR = P2 / P1. For example, air entering at 1 atm and leaving at 6 atm gives a CPR of 6. This concept is about pressure increase, not the difference in pressure, temperature, or summing stage pressures.

The compressor pressure ratio is defined as the outlet pressure divided by the inlet pressure. It’s a dimensionless value that shows how much the compressor increases the air pressure as it passes through. In practice, you measure the inlet pressure (P1) and the outlet pressure (P2) and compute CPR = P2 / P1. For example, air entering at 1 atm and leaving at 6 atm gives a CPR of 6. This concept is about pressure increase, not the difference in pressure, temperature, or summing stage pressures.