Analysis And Optimization Of The Manifold Mechanism Of The Inlet Test Device

The splitter plate mechanism is an important mechanism in the combined cycle inlet modal conversion device,and it is responsible for the important task of adjusting the intake air volume of the upper and lower runners and completing the modal conversion.Since the manifold mechanism has to withstand the impact of high Mach number gas,it is necessary to perform multi-objective optimization on the manifold mechanism to achieve the best performance.Considering the influence of its structural parameters on the natural frequency,strength and elastic deformation of the system,a multi-objective optimization optimal solution is obtained,which provides a reference for the preliminary comprehensive design and product optimization update of the gas distribution mechanism in this type of special environment.This article mainly includes the following contents:First,according to the design requirements of the intake port splitter device,the mechanism is preliminarily designed,and the theory needed for the subsequent mechanism optimization design process is explained.After considering the dead center and reliability of the manufacturing cost mechanism,the arc guide rail type parallelogram mechanism was selected as the development plan among a variety of plans.Considering the movement pair clearance modeling method and the stress-strength interference model,using the first-order second moment method,the movement accuracy reliability function of the splitter mechanism is established,and the movement accuracy reliability of the mechanism under different movement pair clearances is analyzed.Secondly,using the Euler–Bernoulli beam model,D’Alembert’s principle is used to establish the free equation of bending vibration of the variable cross-section member distributor plate.The engineering software ANSYS was used to calculate the influence of the design parameters on the natural frequency of the shunt plate,and the mathematical relationship between the structural parameters and the natural frequency was fitted.According to the steady-state characteristics of the flow field,the force of the splitter member is decomposed,the mathematical expression of the deflection curve of the splitter member is obtained by the integral method and the superposition method,and the deflection calculation expression proposed is verified by the ANSYS engineering software.Finally,the multi-objective optimization mathematical model of the manifold multilink mechanism is established and the parameter optimization results are obtained.Use NSGA-II algorithm to obtain the Pareto optimal solution set of multiple objective functions,use the AHP method to establish the priority matrix of each objective function,and determine the function evaluation coefficient according to the 1-9 scale method,and finally Obtain the optimal result under the mutual restraint of each objective function.Based on the above optimized structural parameters,product design,processing and manufacturing of the research institution were carried out,and finally the air inlet modal conversion wind tunnel test was carried out.The shunting process was recorded by a highspeed camera,which further verified its stability and its precision in the harsh experimental environment.