CAJ | 학술논문

通气发房是民机风洞试验中模拟发动机效应的一种有效手段。通过调整通气发房出口面积，可以对通过发房的流量进行控制，实现所需模拟的流量系数，保证进气流场的几何相似性。失速特性是民机的一个重要的性能指标，大量的低速风洞试验工作都着眼于着落构型下失速特性的研究；而在失速特性的适航审定试飞时的发动机将处于慢车功率状态，因此以模拟慢车流量系数作为低速风洞试验通气发房的设计目标，有助于在风洞试验中对失速特性进行预测。慢车功率时，由于发动机风扇压比很小，如保留外涵喷口形状，通气发房还能近似模拟风扇的喷流效应。发动机在慢车功率下的流量系数在0.5附近，为实现这一流量系数，在设计通气发房时，需调整内涵出口面积，使发房的总出口面积接近唇口面积的一半。 CFD计算证明这种设计方法得到的通气发房基本能够实现预期的流量系数。
통기발방시민궤풍동시험중모의발동궤효응적일충유효수단。통과조정통기발방출구면적，가이대통과발방적류량진행공제，실현소수모의적류량계수，보증진기류장적궤하상사성。실속특성시민궤적일개중요적성능지표，대량적저속풍동시험공작도착안우착락구형하실속특성적연구；이재실속특성적괄항심정시비시적발동궤장처우만차공솔상태，인차이모의만차류량계수작위저속풍동시험통기발방적설계목표，유조우재풍동시험중대실속특성진행예측。만차공솔시，유우발동궤풍선압비흔소，여보류외함분구형상，통기발방환능근사모의풍선적분류효응。발동궤재만차공솔하적류량계수재0.5부근，위실현저일류량계수，재설계통기발방시，수조정내함출구면적，사발방적총출구면적접근진구면적적일반。 CFD계산증명저충설계방법득도적통기발방기본능구실현예기적류량계수。
Through-flow nacelle ( TFN) is an effective method of simulating engine effect in wind tunnel Testing. By adjusting the nozzle exit areas of a TFN, the flow passing the TFN could be controlled and the flow ratio ( MFR) could be achieved to make sure the similarity around the inlet flow field. As stall characteristics is one of the impor-tant factor in defining civil aircraft performance, a great portion of the low speed wind tunnel tests is devoted to the study of the stall characteristics of aircraft in landing configuration;and due to the fact that engines tend to be set at an idle condition during airworthy flight tests for stall speed determination, designing a TFN with a MFR corre-sponding to an idle power setting is desirable for the prediction of stall characteristics in wind tunnel testing. When running at idle conditions, an engine will have a very low fan pressure ratio, which means if the fan nozzle geometry is maintained, TFN can also be used to simulate approximately the jet effects of idle power setting. A engine run-ning idly will have a MFR of around 0 . 5 , which can be achieved on a TFN which is designed such that the total nozzle area is half of the highlight area. CFD calculation has proved the effectiveness of this methodology.