Experimental and numerical study of novel tip configurations in a turbine cascade

Abstract

Two novel tip modelling methods are proposed in this paper. One novel tip is established by the mathematical method and the other is generated by the B-spline surface. And the genetic algorithm, the orthogonal design and the Kriging model are applied to optimize two kinds of novel tips numerically. The optimal mathematical tip and the optimal B-spline tip are acquired, respectively. The aerodynamic tests were investigated at the wind tunnel test section, including the flat tip, the squealer tip, the optimal mathematical tip and the optimal B-spline tip. The static pressure distributions on the casing and the blade surface were measured by the pressure taps. Meanwhile, the secondary flow and the loss were obtained by the five-hole probe at the exit section. A comparison of the simulation analysis results with the experimental results shows good agreement. Compared with the flat tip, the measured loss on the squealer tip, the optimal mathematical tip and the optimal B-spline tip is decreased by 7.2%, 10.5% and 12.6%, respectively.