某高超声速风洞模型底压精确测量方法改进研究与试验验证

Technology research and test verification of the model bottom pressure measurement in the hypersonic wind tunnel

摘要:

针对某高超声速风洞模型底压量值低精确测量难度大、底压传感器容易过温超载等问题，在某高超声速风洞中建立了一套可精确测量风洞模型底压的专用装置。该装置采用了小量程绝压式薄膜电容规作为主要的测量元件，并有针对性的设计了传感器过压保护气路、水冷隔热结构和测控程序。该装置布置于该风洞试验段内模型支撑机构上，可大幅缩短测压气路，减少转接环节。该装置在马赫数5～9试验条件下开展了HB-2标模试验验证，试验结果表明：该模型底压精确测量装置达到了设计要求，集成度高，故障率低，系统稳压时间显著缩短，可快速响应模型底部压力变化情况，可适应高马赫数试验条件下模型底压测量要求，系统测量精度优于0.5%，能大幅度提高了高超声速风洞模型底压测量的精准度。

Abstract:

Aiming at the problem of measuring the model’s bottom pressure with low value and overheat threat of the pressure sensor, a special device was established in hypersonic wind tunnel to accurately measure the bottom pressure. The device uses small range absolute pressure film capacitor gauge as the main measuring element, and targeted design of sensor overload protection gas path, water cooling heat insulation structure and control program. The device is arranged on the model support mechanism of the wind tunnel test section, which can greatly shorten the pressure measuring gas path and reduce the switching link. The device was tested with HB-2 model at Mach number 5~9, the test results show that: The model’s bottom pressure precision measuring devices meet the design requirements, with high integration, low failure rate, the pressure stabilization time could be shortened significantly, and the device can response bottom pressure of the model change rapidly, can adapt to bottom pressure measurement requirement at high Mach number, the measurement precision is better than 0.5%, can greatly improve the accuracy of the model’s bottom pressure of the hypersonic wind tunnel.