What is the maximum speed of a turbofan?
Turbofans are the most efficient engines in the range of speeds from about 500 to 1,000 km/h (270 to 540 kn; 310 to 620 mph), the speed at which most commercial aircraft operate. In fact, turboprop engines are also more efficient than turbofan engines, but aircraft speeds using turboprop engines are typically lower than those of turbofan engines.Turboprops are most efficient and perform best at low altitude and airspeeds up to Mach 0. Turboprops and turbofans are independent solutions for independent design goals and problems.
What is the pressure ratio in a turbofan?
The integrated engine pressure ratio (IEPR) is a ratio used on some turbofans to include fan discharge total pressure and compressor inlet total pressure. If compressor inlet pressure is P0 and fan discharge total pressure is P1, then the integrated engine pressure ratio will be P1 /P0. The engine pressure ratio (EPR) is the ratio of the turbine exit pressure to the engine intake pressure.