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基于五阶空间离散精度的WCNS格式,开展了CRM翼身组合体模型的高阶精度数值模拟,以评估WCNS格式对复杂外形的模拟能力以及典型运输机巡航构型阻力预测的精度。首先依照DPW组委会提出的网格生成指导原则,利用ICEM软件生成了粗、中、细、极细四套网格,网格规模从“粗网格”的2 578 687个网格点逐渐扩展到“极细网格”的65 464 511个网格点。研究了设计升力系数下,网格规模对气动特性、压力分布和翼根后缘局部分离区的影响,采用“中等网格”开展了抖振特性的数值模拟研究。通过与二阶精度的计算结果、DPW V统计结果和部分试验结果的对比分析,高阶精度数值模拟结果表明,阻力系数计算结果与DPW V统计平均结果吻合较好;网格密度对机翼上表面的激波位置和翼身结合部后缘局部分离区略有影响;迎角为4°时,升力系数下降的主要原因是机翼上表面激波诱导分离区和翼身结合部后缘局部分离区的增加。
Based on the WCNS format of fifth-order spatial discretization, high-order precision numerical simulation of CRM wing-body combination model is carried out to evaluate the accuracy of WCNS format’s ability to simulate complex shape and resistance prediction of typical transport aircraft cruise configuration. Firstly, according to the guideline of grid generation proposed by DPW Organizing Committee, a total of 2 578 687 grids of coarse, medium, fine and very fine grids with a grid size of “coarse grid” were generated by ICEM software The dots gradually expanded to 65 464 511 grid points of the “very fine grid”. The influence of the grid size on the aerodynamic characteristics, pressure distribution and the local separation zone of the trailing edge of the root was studied under the design lift coefficient. The numerical simulation of the chattering characteristics was carried out by using the “medium grid”. Through the comparison with the results of second-order precision, DPW V and some of the test results, the numerical simulation results of high-order accuracy show that the calculated result of the drag coefficient agrees well with the statistical average of DPW V; The surface shock position and the wing body junction trailing edge of the local separation zone slightly affected; angle of attack of 4 °, the main reason for the decline in lift coefficient is the wing surface of the shock induced separation zone and wing junction with the trailing edge of the local Increase in the separation zone.