Method for adjusting and designing outlet area of engine jet pipe based on installation performance

Abstract

The invention discloses a method for adjusting and designing the outlet area of an engine jet pipe based on installation performance. Engine zero dimension calculation software is adopted to calculate section parameters and adjustable sectional area of an engine according to a main adjustment plan, limit values, a flight altitude and a mach number of the engine, wherein 101% of the current throat area of the jet pipe is taken as a minimum value, and 250% of the throat area is taken as a maximum value; the series outlet area of the jet pipe is divided equally into 13 parts; a jet pipe flow field at various outlet area conditions is calculated by flow field calculation software; non-installation thrust and afterbody drag of the engine jet pipe are after-processed and calculated by the flow field calculation software; a maximum value of the sum of the non-installation thrust and the afterbody drag is selected; and the outlet area, which corresponds to the maximum value, of the jet pipe is the optimum outlet area of the jet pipe at the condition. The method has the advantages that the installation thrust of the engine can be effectively improved on the premise that the structure of the engine jet pipe and the working state of the engine are not changed.

Description

technical field [0001] The invention relates to the technical field of aircraft with an actively adjustable engine nozzle outlet area, in particular to a design method for adjusting the engine nozzle outlet area based on installation performance. Background technique [0002] Existing aero-engine nozzle outlet area adjustment plan design only considers the non-installation performance of the engine, and now advanced fighter jets require long-term supersonic cruise without afterburner. As the cruise speed increases, the flight resistance increases. The main components that analyze the resistance of the aircraft are: wings, fuselage, empennage, canopy and landing gear, among which the resistance of the rear body of the fuselage accounts for 38-50% of the total aircraft resistance. However, the nozzle outlet area has a great influence on the after-flight body resistance. Therefore, only considering the non-installation thrust has limited the installation performance of the prop...

AI Technical Summary

Problems solved by technology

However, the outlet area of ​​the nozzle has a great influence on the body resistance after flight. Therefore, when designing the adjustment plan for the outlet area of ​​the engine nozzle, only considering the non-installation thrust has limited the performance of the installation performance of the propulsion system.

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