The process of ski jumping is divided into four parts: skiing, jumping, air flight, and landing. Athletes can achieve a stable flights attitude within 0.5s after jumping, and then basically keep their attitude unchanged to complete the air flight, so the lift-to-drag ratio of the air flight process and the stability of the athlete’s attitude directly determine the distance of the jump, thus affecting the performance of the competition. There are many factors affecting the aerodynamic characteristics of the aerial flight stage of ski jumping, such as windward angle, body and snowboard angle, V-shaped angle of snowboard and relative inclination between skis. Computer fluid dynamics (CFD) simulation is an important tool for studying the stability of the air flight phase, which can simulate the air flow and stress statue of the human/board system in the actual motion. At present, this research mainly analyzes the univariate influence of body posture and ski posture, but there are few studies on the multi-factor coupling relationship between the above.
This article used the human/board system of the platform as the research object to explore the air resistance that it suffered during the air flight and the torque problem that needed to be overcome. Combined with the main parameters of human and board system gesture during the air flight, that is, relative inclination between skis, body and snowboard angle, and V-shaped angle of snowboard are used for simulation analysis. It can be seen that ski-jumping involves multi-factor coupling analysis, and three-factor four-level simulation will be carried out through CFD simulation method. Since the number of experimental models reached 43=64, the number of models was large, so the orthogonal test design method was used to carry out simulation tests. The numerical results were processed, and the optimal level combination of single target was analyzed first, the optimal level combination when multi-target factors were coupled, and finally the obtained excellent level combination was modeled and simulated to determine the optimal level combination of the three-factor coupling of the final human/board system. By analyzing the posture angle of athletes in the actual competition of the Beijing 2022 Winter Olympics, the simulated pose was verified.
The results showed that there was a coupling relationship in the main parameters of the human/board system posture during the air flight. The optimal level of single factor can not ensure that the optimal angle can also be reached after other pose angles are changed. The total lift-drag ratio, skiing board lift-drag ratio, physical torque and ski board torque human/board system will have an impact, and can indirectly affect the pneumatic characteristics and attitude stability of the athletes during the air flight. The optimal combination of the human/board system was that the relative inclination between skis was 120°, The body and snowboard angle was 26°, and the V-shaped angle of snowboard was 32°.
The smaller relative inclination of the skis can improve the aerodynamics of athletes during flight. The conclusion of the angle between body and snowboard and V-shaped angle of snowboard is based on the standard platform (male) athletes of the 2022 Beijing Winter Olympics as the research object, and the parameters such as body and snowboard angle, V-shaped angle of snowboard and average jump distance of stable human/board attitude are obtained by video analysis, and the statistical results verify the reliability of the research results.