摘要
Abstract
The trim problem of aircraft with redundant control surfaces is a hyperstatic problem.To determine the appropriate trim configuration,three single trim configuration optimization problems were constructed from the perspective of performance requirements.Under a fixed level flight state at an altitude of 5 km and Mach number of 0.8,genetic algorithm was used to solve the problem.Aiming for maximum lift to drag ratio,use inner lift aileron trim and keep the remaining control surfaces neutral;To achieve the objective of reducing control energy by minimizing the absolute deviation angle of the control surface,the mid lift aileron configuration is adopted to trim,while the remaining control surfaces are neutral;To achieve the objective of reducing radar reflection by minimizing the deviation angle difference between control surfaces,three sets of lift ailerons are simultaneously tilted up by 3.7882°.Based on aerodynamic data,the rationality of the above results was analyzed.Combining three single objective problems pairwise and using a non-dominated sorting genetic algorithm to solve,Pareto non inferior solutions were obtained.It was found that the three balancing objectives were conflicting pairwise,and improving the performance of one objective would reduce the performance of the other objectives,but the proportion of performance reduction was different.Taking into account three optimization objectives,The ideal point minimum distance method is adopted to select the optimal configuration from Pareto non inferior solutions.The final trim configuration is 1.7908°angle of attack,-0.0009588°inner lift aileron,-4.1908° middle lift aileron,and-4.9232° outer lift aileron.Based on performance requirements,an optimization model is constructed for balancing,and combined with the ideal point minimum distance method.The investigation of this paper has certain reference significance for the reasonable calculation of the trim configuration and performance comprehensive analysis of aircraft with redundant control surfaces.关键词
冗余控制面/超静定配平/多目标优化/理想点最小距离法Key words
redundant control surface/overdetermined trim/multi-objective optimization/ideal point minimum distance method
