A perfectly parallel optimisation for cutback trailing edges

摘要：

　　Previous attempts have been made to optimise the performance of film cooling slots for cutback trailing edges,but these have made use of steady methods,which have been shown to be inappropriate for accurately capturing the performance of this class of flows.Here,an unsteady method — large eddy simulation on a coarse grid,or very large eddy simulation,(VLES)— is used to simulate each flow.To take advantage of the enormous parallel capacity of modern supercomputers and distributed computing nets,and the relatively low cost of VLES,as well as to mitigate its low scope for significant parallelisation,a perfectly parallel evolutionary optimisation process was chosen.A crude optimisation aim is used to maximise the adiabatic wall film cooling effectiveness averaged over the entire cutback surface,as a proof of concept.The optimising heuristic then used an evolutionary approach to design an improved turbulator planform,subject to some imposed design restrictions.Six hundred LES type simulations were carried out over 12 generations,and the best performing designs from the last generation is analysed.The optimised design showed a considerable improvement in the target metric over the original designs.The influence of various geometric parameters on several of the metrics of film cooling is also examined,by extracting data from the populations generated over the course of the optimisation.In a more targeted optimisation exercise,it is likely that this data could be used to steer the course of the evolution down favourable paths more quickly.

关键词： Large eddy simulation Genetic algorithm Cutback trailing edges High pressure turbine Film cooling Optimisation Parallelisation Computational efficiency Adiabatic wall film cooling effectiveness

作者: Rob Watson Paul G. Tucker

作者单位: Department of Engineering,University of Cambridge,Cambridge,CB2 1PZ,United Kingdom

会议类型: 国际会议

会议名称: The 5th International Symposium on Jet Propulsion and Power Engineering(第五届喷气推进与动力工程国际会议)

会议地点: 北京

会议语种:英文

页码: 1-11

在线出版日期: 2014-09-15（万方平台首次上网日期，不代表论文的发表时间）