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。
High-order numerical simulation on CRM wing-body model is presented with the fifth-order WCNS scheme to as- sess the ability of high-order WONS scheme on complex configuration simulation and the precision in predicating cruise drag of transonic configuration. Four grids (coarse, medium, fine, and extra fine) are created with software ICEM according to the gridding guidelines provided by DPW organizing committee, and the grid sizes range from 2 578 687 cells for the "Coarse" level to 65 464 511 cells for the "Extra-fine" level. Computation and analysis on four grids are carried out to inves- tigate the grid effect on aerodynamic characteristics, pressure distribution and the local separation bubble at the wing root trailing edge, and the "Medium" grid is used in the numerical simulation and study of buffet onset. Compared to second-order numerical results, the statistic results submitted by DPW V participants and some experimental data, the high-order numeri- cal results show that the drag coefficient computational results agree well with statistic data from DPW V participants; the grid density has some influence on the location of the shock wave and the size of the local separation bubble at the wing root trailing edge; the enlargement of the size of the separation zone due to shock wave and the local separation bubble at the wing root trailing edge on the upper surface of the wing is the main reason of the lift lift curve break at 4° angle of attack.