高超声速风洞流场非均匀性对气动力试验影响研究

Effects of Non-Uniformity of Flow Field on Aerodynamic Test in Hypersonic Wind Tunnel

关键词:  高超声速风洞  流场  气动力  多位置试验  重复性试验误差

Key words:  Hypersonic wind tunnel  Flow field  Aerodynamic force  Multi-position test  Repeatability error

摘要:

高超声速风洞流场非均匀性是气动力试验误差的主要来源，但其具体影响程度还不能量化。以升力体飞行器模型和通气模型为研究对象，分别在CARDC Φ1m和Φ2m高超声速风洞中开展了“多位置试验”研究，得到了高超声速风洞流场非均匀性和常规气动力试验数据的影响关系，并对风洞试验数据重复性、初始不确定度、两座风洞试验差异等数据进行了对比分析。试验结果表明：高超声速风洞流场的非均匀性对飞行器气动力（特别是力矩特性）试验结果有显著影响，这种影响量已远超过常规的风洞重复性试验误差，甚至大于在AIAA-S071A-1999标准上建立的不确定度评估方法所获取的“不确定度”；选取流场马赫数偏差较小区域开展风洞试验可有效减小由流场非均匀性引起的气动力试验结果偏差。

Abstract:

The flow field non-uniformity of hypersonic wind tunnel is the key factor of aerodynamic test error. However， its influence cannot be quantified. A lift vehicle and an air-breathing model were taken as the research object， multi-position experiments are carried out in Φ1m and Φ2m hypersonic wind tunnels of CARDC. The relationship between flow field non-uniformity and hypersonic wind tunnel experiment data is obtained. The repeatability and initial uncertainty of wind tunnel experiment data were compared and analyzed. The experiment results show that the non-uniformity of wind tunnel flow field has a significant influence on the aerodynamic （especially the moment characteristics） test results of the aircraft.This influence is far greater than the repeatability error of conventional wind tunnel， and even greater than the uncertainty evaluation based on the AIAA-S071A-1999 standard. At the same time， the wind tunnel experiment should be carried out in areas with small Mach deviation of flow field， the deviation of aerodynamic experiment results which was caused by flow field non-uniformity can be reduced.