【摘要】 目的:分析研究滑雪板夹角对跳台滑雪飞行阶段气动特性的影响。方法:建立精细化三维几何模型与网格模型,采用部分时均(partially averaged Navier-Stokes,PANS)湍流模型对气动特性进行计算流体力学(computational fluid dynamics,CFD)数值模拟,获取不同滑雪板夹角下(24°、28°、32°、36°和40°)力和力矩、压力分布以及流场形态。结果:1)总升力与总阻力、升力系数与阻力系数、总力矩与滑雪板力矩均随滑雪板夹角增大先减小后增大最后小幅减小,但总升阻比基本保持不变,总体呈略微下降趋势;2)滑雪板升力随滑雪板夹角增大呈现单调递增的趋势,而滑雪板阻力随滑雪板夹角增大先减小后增大;3)滑雪板正面压力分布规律基本相同且比较均匀,而滑雪板背面下半部分压力随滑雪板夹角变化比较明显;4)运动员身后以及滑雪板身后的流场形态主要以回流涡形式出现,滑雪板背面回流涡结构明显比运动员身后复杂得多,而且回流涡强度也明显大得多。结论:1)滑雪板夹角变化对总升阻比影响很小,但对总升力、总阻力、升力系数以及阻力系数产生一定影响,同时对运动员气动特性也产生一定影响。2)滑雪板气动特性在运动员/滑雪板整体系统中起着更为重要作用,不仅要关注运动员身体姿态,而且应更加关注滑雪板姿态;3)总力矩大小和滑雪板力矩大小随滑雪板夹角变化趋势一致,而且滑雪板力矩在总力矩中始终占据主导地位,选取合适的滑雪板夹角对飞行阶段稳定性至关重要,建议优选的滑雪板夹角范围为24°~32°。更多还原

【Abstract】 Objective: This study aimed to investigate the effects of the ski opening angle on aerodynamic characteristics during the flight in ski-jumping. Methods: Refined 3D geometric models and mesh models were established, and aerodynamic characteristics were numerically simulated by using computational fluid dynamics(CFD) with partially averaged Navier-Stokes(PANS) turbulence model. The force and moment, pressure distribution and flow field form of different ski opening angles(24°, 28°, 32°, 36° and 40°) were obtained. Results: 1) As ski opening angle increases,the total lift force and that drag force, the coefficients of lift and drag, the total torque and the skis’ torque all decrease firstly, then increase, and finally decrease slightly, but the total lift-to-drag ratio almost remains unchanged, and shows a slight downward trend as a whole. 2) The skis’ lift force increases monotonously with the increase of ski opening angle, while the skis’ drag force decreases firstly and then increases. 3) The front pressure distribution of skis is approximately the same and fairly uniform, but the back pressures distribution of the lower part of skis varies obviously with ski opening angle. 4) The flow field form behind athlete and skis mainly appears in the form of reflux vortex. The vortex structure behind skis is much more complicated than that behind the athlete, and the vortex intensity is also much greater. Conclusion: 1) The ski opening angle has little effect on the total lift-to-drag ratio, but has some influence on the total lift and total drag and the coefficients of lift and drag, as well as on the aerodynamic characteristics of the athlete. 2) The aerodynamic characteristics of skis play a more important role in the whole athlete/skis system, so more attention should be paid to skis’ attitude while paying attention to athletes’ body posture. 3) The variation trend of total torque and skis’ torque with ski opening angle is consistent, and skis’ torque has always been dominant in the total torque, so it is very important to select the proper ski opening angle for the stability of flight phase, and it is suggested that the optimum range of ski opening angle is 24°~32°.更多还原