Research on analysis method of propulsive efficiency of prop-fan engine

Abstract

It is of great significant for prop-fan engine under medium to high Mach number to evaluate the propulsive efficiency of turbofan, turboprop and prop-fan engines. The mathematical model for propulsive efficiency analysis is established by using energy-momentum method based on the model of separate exhaust turbofan engines, and a unified propulsive efficiency analysis method is formed for turbofan, prop-fan and propeller fan engines. Different external fan pressure ratios, equivalent bypass ratios and different flight Mach number are selected for calculation. The results show that the propulsion efficiency of turboprop engine is higher at medium to low flight Mach number, the propulsion efficiency of prop-fan engine is higher at medium to high flight Mach number, and the propulsion efficiency of turbofan engine is higher at high subsonic flight Mach number. The existing flight Mach number interval distribution law of the superior propulsion efficiency of turboprop, prop-fan and turbofan engines is conformed. The study can provide a method for the research and analysis of the propulsion efficiency of turbofan, turboprop and prop-fan engines.

Keywords

• prop-fan engine
• bypass ratio
• propulsion efficiency
• mathematical model