Method for front fuselage high incidence boundary layer transition in a rolling and oscillating process of model

Abstract

The invention provides a method for front fuselage high incidence boundary layer transition in a rolling and oscillating process of an experimental model. In the method, a plurality of transition wires are arranged on two sides of the windward side of a front fuselage, so that in the process of rolling and oscillating at a certain amplitude of the model, one of the transition wires always exists in a circumferential angle of circumferential flow, which defines the transition range in wind axes of the slender front fuselage, and each transition wire is stuck from a specific position at the front end of the model to a section at front ends of airfoils. Therefore, the purpose of researching the rolling and oscillating motions of the forebody of a model airplane in a circumferential flow state above critical Reynolds number in a conventional low-speed wind tunnel is realized.

Description

Technical field [0001] The present invention involves a wind tunnel experiment method in the field of aerospace, especially the front airment method of the front aircraft of the experimental model during the dynamic roll of the experimental model in the big attack angle. Background technique [0002] Modern fighter jets usually require a large -scale attack angle mobile flight to improve its combat effectiveness. Fighters often have horizontal instability in the state of large attack angles, producing uncontrollable non -linear flight movements, such as wing rock phenomenon (wing -body combination model model model modelThe large amplitude of the body shaft oscillation).In addition, fighters also need to actively do horizontally rolling in the big attack angle to achieve certain motor movements.Therefore, it is usually necessary to study the pneumatic characteristics and streaming characteristics of the fighter in the wind tunnel to do horizontally rolling or oscillation.For mode...

AI Technical Summary

Problems solved by technology

[0004] But when the experimental model rolls and oscillates, attaching transition wires according to the method of Chen Ying, Deng Xueying, etc. does not make the slender spiral body on the wing-body assembly The flow around the front fuselage has always maintained a supercritical flow state. The reason is that the transition wire plays a transition role in the range of about ±(48°-71°) around the model’s circumferential angle (wind shaft system). Once the model rolls Oscillation, if the transition wire exceeds this angle range in the wind shaft system, the artificial transition effect will be invalid

For the wing rock motion of the wing-body assembly, the amplitude is generally in the order of 40-60 degrees, which can easily exceed the transition range of the transition wire

At present, under the roll oscillation condition of the experimental model, there is no report on the technology for the simulation of the transcritical flow state of the front fuselage of the aircraft.

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