层流机翼飞行验证平台雷诺数效应分析及修正

Analysis and correction of Reynolds number effect of a flight verification platform with laminar wing section

在飞机设计阶段,获得真实准确的气动特性数据对设计方案的改进和定型都十分重要。然而,当前在设计初期所采用的缩比模型风洞试验存在一定的局限性,预测的气动数据也难以同真实飞行情况下完全一致,雷诺数效应便是导致这种差异的最主要原因之一。采用CFD数值模拟方法针对特殊布局形式的层流机翼飞行验证平台低速起降和高速巡航构型分别在试验和飞行雷诺数下进行数值模拟分析。通过计算所得全机气动力系数与风洞试验数据的对比分析,验证了本文数值模拟结果的可靠性和准确性,同时也佐证了风洞试验数据的有效性。通过计算所得高、低速力系数,流场结果和高速层流区长度的对比,分析总结得到雷诺数效应对验证平台高低速气动特性、低速失速分离特性以及高速层流转捩特性的具体影响规律,并据此对低速和高速试验数据进行修正,为后期飞行试验的设计提供数据支撑。

In the preliminary design stage of the aircraft, it is very important to obtain true and accurate aerodynamic characteristics for the improvement and finalization of the aircraft design process. However, the current scaled model wind tunnel tests used at the initial stage of the design have their own limitations and the predicted aerodynamic data are not always consistent with the real flight conditions, with the Reynolds number effect being one of the main causes of this discrepancy. In this paper, CFD numerical simulation method is used to analyze the two configurations of the flight verification platform with and without the high-lift device opening under test and flight Reynolds number, respectively. The reliability and accuracy of the numerical simulation results are verified by comparing the calculated aerodynamic coefficients with the wind tunnel test data, which also supports the validity of the wind tunnel results. And the comparisons of the calculated aerodynamic coefficients at low and high speed conditions, the transition location on the upper surface of the laminar wing section and the results of the flow field are further proposed to clarify the specific effects of Reynolds number on three key aspects of the verification platform with special layout, including the aerodynamic performance, the low-speed stall characteristics and the high-speed laminar transition characteristics. The results and laws obtained from the above tests, calculations and analysis can be used for the correction of the Reynolds number effects and provide sufficient data to support the design of the later flight tests.