Aerodynamic optimization method of variant aircraft based on improved position vector expectation improvement

Abstract

The aerodynamic optimization method of a variant aircraft for improving the expected improvement degree of the position vector disclosed by the invention belongs to the technical field of overall optimization of the aircraft. Select the initial reference airfoil and related shape coefficients to determine the design conditions; establish an optimization model considering structural consistency constraints to solve the shape coefficient of the deformed airfoil, and establish a high-precision aerodynamic analysis model to solve the lift coefficient and drag coefficient of the airfoil; establish The Kriging surrogate model of the high-precision aerodynamic analysis model, optimize the Kriging surrogate model to obtain a pseudo-non-dominated solution, and determine whether the prediction variance of the Kriging surrogate model is greater than the threshold; if the prediction variance is not less than the threshold, use the position vector expectation improvement criterion to obtain new samples The point is used to update the Kriging surrogate model, otherwise the new sample points are filtered from the pseudo-non-dominated solution to update the Kriging surrogate model. By filtering new sample points, the accuracy of the Kriging surrogate model at the Pareto frontier is improved, the optimality and distribution of the optimized non-dominated solution are improved, and the optimization efficiency is improved and the cost is saved.

Description

technical field [0001] The invention relates to an aerodynamic optimization method for a variant aircraft based on the expected improvement degree of the improved position vector, and belongs to the technical field of overall aircraft optimization. Background technique [0002] Traditional aircraft generally use a fixed aerodynamic layout, which can achieve optimal aerodynamic performance only under specific flight conditions, and has limited multi-task capability. The variant aircraft can autonomously change its aerodynamic shape according to different flight environments and combat missions, thereby improving its aerodynamic performance. The variable-wing aircraft in the variant aircraft can adjust the lift-to-drag ratio to adapt to different flight conditions by changing the camber or thickness of the airfoil, or make the airfoil obtain different front and rear edge camber by means of the deformation of the front and rear edges of the airfoil, instead of the traditional c...

AI Technical Summary

Problems solved by technology

[0018] Aiming at the problems in the aerodynamic multi-objective optimization design of the variable-wing aircraft, the internal structure is insufficiently considered for the limitation of the deformation capability, and the calculation of the optimization process is complicated. The technical problem is to describe the constraints of the wing internal support structure and drive device on the deformation capability of the variable-wing aircraft by customizing the airfoil geometry parameterization method considering the structural consistency constraints, and through the multi-objective optimization based on the expected improvement of the improved position vector The method balances the distribution and optimality of the non-dominated solutions to realize the efficient optimization of the variable-wing aircraft. The aerodynamic performance of the airfoil aircraft under different flight conditions improves the ability of the aircraft to perform multiple tasks, making the airfoil aircraft have a wide range of practicability and versatility, thereby reducing the cost of research and development

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