Abstract:Abstract:Objective Key technical parameters during ski jumping's takeoff and flight phases greatly affect performance. Yet, most studies focus on kinematic analysis, lacking aerodynamic research into the link between these two phases' aerodynamic features. Thus, it is necessary to explore the aerodynamic characteristics of different performances in the dynamic process from takeoff to flight. Methods A refined model of the athlete/ski system was established. Utilizing CFD simulations, we apply SPM methods to compare aerodynamic differences in various motion performances during the dynamic transition from takeoff to flight, encompassing lift, drag, lift-to-drag ratio, and torque. Additionally, we selected representative cases to observe changes in pressure, flow field, and vorticity intensity distribution. Results The SPM test results indicated that the total lift achieved by the long-distance group during the 90-100% phase of the takeoff and flight process significantly surpassed the threshold (P=0.02, tcrit=3.29). Although the total drag throughout the entire process was lower than that of the close-range group, the difference was not statistically significant (P>0.05, tcrit=3.44). The total lift-to-drag ratio notably exceeded the threshold during the 92-100% phase (P=0.01, tcrit=3.53), and the total torque significantly exceeded the threshold during the 77-100% phase (P<0.001, tcrit=3.33). The jump with the longest flight distance evidently experienced less pressure during the dynamic process, exhibiting a clearer and smoother velocity streamline, along with a weaker reflux vortex. Conclusions Research has found that, compared to ordinary athletic performance, excellent athletic performance exhibits superior aerodynamic effects, particularly during the initial flight phase until a stable flight posture is established.