空气动力学学报
空氣動力學學報
공기동역학학보
ACTA AERODYNAMICA SINICA
2014年
4期
527-533
,共7页
剪刀式尾桨%气动力%CFD%N-S 方程%嵌套网格
剪刀式尾槳%氣動力%CFD%N-S 方程%嵌套網格
전도식미장%기동력%CFD%N-S 방정%감투망격
scissors tail-rotor%aerodynamic forces%CFD%N-S equations%embedded grid
建立了一个适用于计算剪刀式尾桨前飞状态气动力的数值方法。在该方法中，采用惯性坐标系下的非定常 Navier-Stokes 方程作为主控方程，使用低数值耗散的 Roe 格式进行空间离散，并应用高效的隐式 LU-SGS 格式进行时间推进；采用双时间法以模拟尾桨前飞时的非定常现象；使用运动嵌套网格方法以计入尾桨桨叶的旋转运动。应用建立的方法，首先对有试验数据可作对比的 Lynx 直升机尾桨悬停状态气动性能进行了计算，验证了所建立方法对尾桨气动性能计算的有效性；同时，针对 Helishape 7A 旋翼进行了前飞状态气动载荷计算，验证了该方法对旋翼（尾桨）前飞气动载荷计算的有效性。最后，对剪刀式尾桨前飞状态进行了气动力计算，并分析了构型参数对剪刀式尾桨气动力的影响。计算结果表明，前飞状态时，相同总距下剪刀式尾桨的平均拉力要大于常规尾桨，且剪刀式尾桨在90°-180°-270°方位角内的桨-涡干扰现象较常规尾桨严重。
建立瞭一箇適用于計算剪刀式尾槳前飛狀態氣動力的數值方法。在該方法中，採用慣性坐標繫下的非定常 Navier-Stokes 方程作為主控方程，使用低數值耗散的 Roe 格式進行空間離散，併應用高效的隱式 LU-SGS 格式進行時間推進；採用雙時間法以模擬尾槳前飛時的非定常現象；使用運動嵌套網格方法以計入尾槳槳葉的鏇轉運動。應用建立的方法，首先對有試驗數據可作對比的 Lynx 直升機尾槳懸停狀態氣動性能進行瞭計算，驗證瞭所建立方法對尾槳氣動性能計算的有效性；同時，針對 Helishape 7A 鏇翼進行瞭前飛狀態氣動載荷計算，驗證瞭該方法對鏇翼（尾槳）前飛氣動載荷計算的有效性。最後，對剪刀式尾槳前飛狀態進行瞭氣動力計算，併分析瞭構型參數對剪刀式尾槳氣動力的影響。計算結果錶明，前飛狀態時，相同總距下剪刀式尾槳的平均拉力要大于常規尾槳，且剪刀式尾槳在90°-180°-270°方位角內的槳-渦榦擾現象較常規尾槳嚴重。
건립료일개괄용우계산전도식미장전비상태기동력적수치방법。재해방법중，채용관성좌표계하적비정상 Navier-Stokes 방정작위주공방정，사용저수치모산적 Roe 격식진행공간리산，병응용고효적은식 LU-SGS 격식진행시간추진；채용쌍시간법이모의미장전비시적비정상현상；사용운동감투망격방법이계입미장장협적선전운동。응용건립적방법，수선대유시험수거가작대비적 Lynx 직승궤미장현정상태기동성능진행료계산，험증료소건립방법대미장기동성능계산적유효성；동시，침대 Helishape 7A 선익진행료전비상태기동재하계산，험증료해방법대선익（미장）전비기동재하계산적유효성。최후，대전도식미장전비상태진행료기동력계산，병분석료구형삼수대전도식미장기동력적영향。계산결과표명，전비상태시，상동총거하전도식미장적평균랍력요대우상규미장，차전도식미장재90°-180°-270°방위각내적장-와간우현상교상규미장엄중。
A numerical method is developed to calculate the aerodynamic forces of scissors tail-rotor in forward flight.In the present method,the three dimensional unsteady Navier-Stokes equations are used as control equations,which are discretized by low dissipation Roe scheme and implicit LU-SGS scheme in space and time directions respectively.Besides,the dual-time stepping method is employed to simulate the un-steady phenomenon of the scissors tail-rotor in forward flight,and moving embedded grid technology is ap-plied to account for rigid blade motion in rotation.Based on the present method,calculations on the aerody-namic performance for the Lynx helicopter tail-rotor in hover are firstly performed to show the capability of the present model in predicting aerodynamic performance of the tail-rotor.Then,simulations for the aerody-namic loads of Helishape 7A rotor are conducted to verify the effectiveness of the numerical method in calcu-lating the aerodynamic forces for forward flight rotors.Meanwhile,calculations on the aerodynamic forces for the scissors tail-rotor in forward flight are performed,and the effects of configuration parameters on the aerodynamic force of scissors rotor are analyzed.The calculated results indicate that,in forward flight,the average thrust of scissors tail-rotor is higher than that of the conventional one with the same blade pitch,and the scissors tail-rotor will suffer more serious BVI than the conventional one in the azimuthal angle range of 90°~180°-270°.
