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.
[1] PETTERSSON K, RIZZI A. Aerodynamic scaling to free flight conditions:Past and present[J]. Progress in Aerospace Sciences, 2008, 44(4):295-313.
[2] MELBER-WILKENDING S, WICHMANN G. Application of advanced CFD tools for high Reynolds number testing[C]//47th AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition. Reston:AIAA, 2009.
[3] BUSHNELL D M. SCALING:Wind tunnel to flight[J]. Annual Review of Fluid Mechanics, 2006, 38:111-128.
[4] SALTZMAN E, AYERS T. A review of flight-to-wind tunnel drag correlation[C]//1st Flight Test Conference. Reston:AIAA, 1981.
[5] OM D, CURTIN M, BOGUE D, et al. Reynolds number effects on a subsonic transport at transonic conditions[C]//39th Aerospace Sciences Meeting and Exhibit. Reston:AIAA, 2001.
[6] HAINES A B. Further evidence and thoughts on scale effects at high subsonic speeds:AGARD CP-174[R]. Paris:AGARD, 1976.
[7] HAINES A B. Scale effects on aircraft and weapon aerodynamics:AGARD AG-323[R]. Paris:AGARD, 1994.
[8] HAINES A B. Prediction of scale effects at transonic speeds:Current practice and a gaze into the future[J]. The Aeronautical Journal, 2000, 104(1039):421-431.
[9] 周林, 杨钊, 李杰. 雷诺数对运输类飞机气动特性影响的试验研究[J]. 应用力学学报, 2019, 36(4):966-970, 1005. ZHOU L, YANG Z, LI J. Experimental investigation on the influence of Reynolds number on aerodynamic characteristics of transport aircraft[J]. Chinese Journal of Applied Mechanics, 2019, 36(4):966-970, 1005(in Chinese).
[10] 巴玉龙, 白峰. 雷诺数对大型客机低速气动特性影响的试验研究[J]. 民用飞机设计与研究, 2016(1):45-47, 88. BA Y L, BAI F. Experimental investigation on effect of Reynolds number on aerodynamic characteristics at low speed for large civil aircraft[J]. Civil Aircraft Design & Research, 2016(1):45-47, 88(in Chinese).
[11] PETTERSSON K, RIZZI A. Estimating Reynolds number scaling and windtunnel boom effects with the help of CFD methods[C]//24th AIAA Applied Aerodynamics Conference. Reston:AIAA, 2006.
[12] SAID M, MAT S B, MANSOR S, et al. Reynolds number effects on flow topology above blunt-edged delta wing VFE-2 configurations[C]//53rd AIAA Aerospace Sciences Meeting. Reston:AIAA, 2015.
[13] RUDNIK R, GERMAIN E. Reynolds number scaling effects on the European high-lift configurations[J]. Journal of Aircraft, 2009, 46(4):1140-1151.
[14] CURTIN M, BOGUE D, OM D, et al. Investigation of transonic Reynolds number scaling on a twin-engine transport[C]//40th AIAA Aerospace Sciences Meeting & Exhibit. Reston:AIAA, 2002.
[15] 周林. 雷诺数对大展弦比运输类飞机纵向气动特性的影响研究[D]. 北京:北京航空航天大学, 2014. ZHOU L. Influence of Reynolds number on longitudinal aerodynamic characteristics of transport aircraft with high aspect ratio[D]. Beijing:Beihang University, 2014(in Chinese).
[16] 马明生, 张耀冰, 邓有奇, 等. 运输机机翼、机身和翼身组合体气动特性雷诺数效应的数值模拟研究[J]. 空气动力学学报, 2011, 29(2):194-198, 204. MA M S, ZHANG Y B, DENG Y Q, et al. Investigation of Reynolds number effects on transport aircraft's wing, fuselage and wing-body by numerical simulation[J]. Acta Aerodynamica Sinica, 2011, 29(2):194-198, 204(in Chinese).
[17] 张培红, 周乃春, 邓有奇, 等. 雷诺数对飞机气动特性的影响研究[J]. 空气动力学学报, 2012, 30(6):693-698. ZHANG P H, ZHOU N C, DENG Y Q, et al. The effects of Reynolds number on airplane aerodynamic characteristics[J]. Acta Aerodynamica Sinica, 2012, 30(6):693-698(in Chinese).
[18] 张彦军, 段卓毅, 魏剑龙, 等. 基于风洞试验和数值模拟的超临界机翼雷诺数修正方法研究[J]. 空气动力学学报, 2018, 36(6):934-940. ZHANG Y J, DUAN Z Y, WEI J L, et al. Research of Reynolds number correction for supercritical wing based on wind tunnel tests and numerical simulations[J]. Acta Aerodynamica Sinica, 2018, 36(6):934-940(in Chinese).
[19] 李中武, 梁益华. 增升装置低速流动特性的雷诺数效应计算研究[J]. 飞行力学, 2014, 32(1):10-14. LI Z W, LIANG Y H. Numerical simulations of Reynolds number effect on flow characteristics at high-lift devices[J]. Flight Dynamics, 2014, 32(1):10-14(in Chinese).
[20] MENTER F R, LANGTRY R B, LIKKI S R, et al. A correlation-based transition model using local variables-part I:Model formulation[J]. Journal of Turbomachinery, 2006, 128(3):413-422.
[21] LANGTRY R B, MENTER F R, LIKKI S R, et al. A correlation-based transition model using local variables-part II:Test cases and industrial applications[J]. Journal of Turbomachinery, 2006, 128(3):423-434.
[22] LANGTRY R B. A correlation-based transition model using local variables for unstructured parallelized CFD codes[D]. Stuttgart:Stuttgart University Press, 2006.
[23] SCHLICHTING H, GERSTEN K. Boundary-layer theory[M]. Berlin:Springer Berlin Heidelberg, 2000.
[24] 恽起麟. 风洞实验数据的误差与修正[M]. 北京:国防工业出版社, 1996. YUN Q L. Error and correction of wind tunnel experimental data[M]. Beijing:National Defense Industry Press, 1996(in Chinese).
CJA