A method for solving aerodynamic model parameters in oblique throwing motion of a sphere

Abstract

The invention discloses a novel calculation method for magnus force coefficients and resistance coefficients in an aerodynamics model. The model and the method aim at projectile motion of a spherical moving object. The method comprises the following steps of utilizing objective flying range data to carry out variable coefficient multielement differential equations calculation through a numerical value iterative method; carrying out layered optimization on obtained feasible solution sets, wherein the first layer is accuracy objective function optimization, and the second layer is smoothness objective function optimization; finally, utilizing the optimization to calculate to obtain the magnus force coefficients and the resistance coefficients, and continuously carrying out iteration solution. The accuracy of the obtained magnus force coefficients and resistance coefficients through calculation is ensured through layered optimization. The method is small in calculated amount and error, only relies on the flying range data under different speeds, can easily acquire the data under a real environment, and has stronger universality.

Description

technical field [0001] The invention relates to the solution of aerodynamic model parameters. Background technique [0002] Oblique throwing is a common form of sports, such as throwing sports, the launching of shells, etc. In practical applications, it is often necessary to calculate the flight trajectory parameters of the target object, such as motion trajectory, flight time, landing position, maximum flight height, etc. [0003] Common motion analysis is based on Newton's law of motion, and the influence of air is ignored according to actual needs. However, for practical problems that require accurate calculation and analysis, the influence of air resistance cannot be ignored. At the same time, when the object has a large angular velocity, different pressures are generated on different sides of the object due to the action of the air, so that the object is subjected to the additional force of the air. This phenomenon is the Magnus effect, and the additional force is call...

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Problems solved by technology

Conventional solution methods are usually obtained by repeated experiments in a wind tunnel at different linear and angular velocities, and only for specific target objects, with a narrow application range, such as the literature "Aerodynamics of a golf ball with grooves" (Jooha Kim , Haecheon Choi, 2009Annual Meeting of the APS Division of Fluid Dynamics) Through wind tunnel experiments, different surface types of spheres were tested at different speeds, and the drag coefficient and Magnus force coefficient were calculated.

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