Basic Design Theory
The performance—thrust or power, fuel consumption, temperatures, shaft speeds, etc.—of a gas turbine engine is crucially dependent upon its inlet and exit conditions. The full range of inlet conditions that a given gas turbine engine application could encounter is encompassed in the operational envelope. This comprises an environmental envelope, defining ambient pressure, temperature, and humidity; installation pressure losses; and a flight envelope for aircraft engines. The environmental envelope for an engine defines the range of ambient pressure (or pressure altitude), ambient temperature, and humidity throughout which it must operate satisfactorily.
Basic design theory; operational envelope; design ...