Abstract: To obtain the energy dissipation characteristics of rough strips arranged in the bends of spillway, a multi-factor influence model of the energy dissipation rate of the rough strips was established based on the research of the Xinjiang “635” spillway rectification project via dimensional analysis. According to the principle of orthogonal experiment, orthogonal test was conducted on the layout of the rough strip energy dissipator in the spillway bend, and multiple regression analysis was accomplished according to the test results to derive the calculation formula of energy dissipation rate reflecting the layout parameters of rough strips and the engineering parameters of the spillway. Moreover, correlation analysis was carried out to explore the influence of each factor, and a dimensionless factor k was defined to reflect the comprehensive characteristics of the rough strip energy dissipator. The findings are concluded as follows: the engineering parameters of spillway have remarkable impact on the energy dissipation rate, while the layout parameters of rough strips have little effect except for the arrangement angle. The dimensionless factor k was in a negative correlation with the energy dissipation rate and the transversal slope of water surface. In addition, changing the layout parameters of rough strips exerted a greater impact on the transversal slope of water surface than the energy dissipation rate. The value of k ranged between 0.016 and 0.049. When the energy dissipation rate reached the peak, k=0.025; when the transversal slope of water surface hit the bottom, k=0.037. As a semi-theoretical and semi-empirical calculation formula, the proposed multi-factor influence model for energy dissipation rate could offer theoretical basis for actual engineering design.

Key words: rough strip energy dissipator, dissipation rate, spillway bend, dimensional analysis, orthogonal design, partial correlation analysis