矢量喷管推力特性的风洞试验技术

该试验技术的研究包括喷流模拟器的研制、地面校准系统的研制、喷管天平数据修正方法研究以及风洞验证试验。研制的喷流模拟器内置喷管推力测量天平,设计了地面推力特性试验校准架,建立了地面试验系统。分析了影响喷管天平测量结果的附加刚度效应、压力效应和流动效应3个主要因素,通过地面校准架建立了相应的测量数据修正方法。针对特定喷管,开展了0°、5°、10°和15°四个偏转角度的喷管,在不同落压比下的推力和矢量角地面验证试验研究。进一步将喷流模拟器和喷管安装在模型上,在中国空气动力研究与发展中心的8m×6m低速风洞开展了落压比为3时的模型纵向气动特性试验研究。研究结果表明:以喷流模拟器为核心的喷管推力特性试验技术能够在地面和风洞试验中有效测量矢量喷管的推力大小、矢量角大小和对飞行器气动特性的影响量。从测量结果来看,落压比为2时,有效推力偏角最大,实际偏角为10°时的有效偏角可以增加3°。喷管偏转10°时,推力对模型的气动力影响最大,其中升力系数可以增加0.066。 

Thrust characteristics test technique of vectoring nozzle in wind tunnel

The research of the test technology includes the development of jet simulator and ground calibration system, the data correction method and the wind tunnel verification test. Jet simulator with built-in thrust balance and calibration system with ground measurement test capability were designed and manufactured. Three main factors affecting the thrust balance measurement results were analyzed, including additional stiffness effect, pressure effect, and flowing effect. Then, a correction method of measurement data was established through calibration system. After that, a ground experimental study on the thrust and thrust angle of the nozzle with four deflection angles at 0°,5°,10° and 15° was carried out under different nozzle pressure ratios. At last, the jet simulator was installed on the aircraft model in 8m×6m wind tunnel of CARDC, and an experimental study on the longitudinal aerodynamic characteristics with nozzle pressure ratio of 3 was carried out. According to the experimental result, this test technique can be used to measure the thrust, the vector angle and the aerodynamic characteristics of the nozzle. From the measurement result, the effective thrust angle of deflection was the maximum when the nozzle pressure ration was 2. At this point, the actual deflection angle was 10°, and the effective deflection angle can be increased by 3°.When the nozzle was deflected by 10°, the thrust had the biggest influence on the aerodynamic force of the model. The lift coefficient can be increased by 0.066.