Simulation of take-off angle of a ski jump energy dissipater

Abstract

Ski jumps has been widely used in water conservancy and hydropower engineering with its simple structure and high energy dissipation. The jet trajectory is a key factor to directly determine the scour location, which are the significant index of hydraulic design. Actually, the take-off angle of jet flow is different from the geometrical take-off angle. Reasonable take-off angle would be quite important for calculation method of horizontal length of jet flow. The object of this work is based on the research of three take-off angels of upper and lower jet trajectories with different outlets (geometrical take-off angle, virtual take-off angle, and computational take-off angle), and provides actual calculation method for horizontal length of ski jumps. On the basis of theoretical analysis and numerical simulation, the main contents and methods of this research report includes: 1) analyzing affective analysis of virtual take-off angles of both the lower and upper jet trajectories, establishing virtual take-off angles of both the lower and upper jet trajectories equations with hydraulic and structure parameters and etc; 2) analyzing by comparing virtual take-off angles of both the lower and upper jet trajectories with different outlets of flip bucket (including circular, triangle, etc.); 3) providing horizontal length of jet flow of ski jumps calculation method with take-off angles of upper and lower jet trajectories.