Experimental Aanlysis And Structural Optimization Design Of Parts Of Large Towing Engine

Large towing engine is an important auxiliary tool for ocean energy development.Towing engine is generally designed for offshore platform construction,cable collection and discharge work.The structure design of the large towing engine is still relatively conservative at the present stage.In the products of the same type of towing engine,the weight of the same type towing engine abroad is about 10% lighter than that of the domestic large towing engine.According to the requirements of parts and components for different performance,the structural optimization design of the parts of towing machine is carried out,and the simulation and experimental verification are carried out.To provide theoretical and technical support for the development of a new structural optimization design method for deck enginery.(1)several multi-objective optimization methods commonly used in mechanical structure optimization design are studied.The advantages and characteristics of various multiobjective optimization methods are analyzed.A multi-objective optimization method based on compromising programming method is selected to optimize the topology of the motor support of towing engine.The finite element technique is used to simulate and analyze the parts of towing engine to be optimized.The motor bracket and the drum of the towing engine are selected as the parts of the optimum design.Static simulation analysis and modal analysis of motor bracket and drum of towing engine are carried out respectively.Modal analysis.The performance of the two parts is evaluated to provide reference value for the subsequent structural optimization design.(2)multi-objective optimization method based on compromise programming method is used to optimize design of motor bracket,where mass,natural frequency and stiffness are taken as objective functions.The quality of the motor bracket is the main optimization objective.The installation position of the motor or motor of the towing engine is analyzed by its dynamic characteristics.The relationship and influence between the objective function of stiffness and the objective function of natural frequency in the process of optimization is unmeasurable and uncertain.In order to solve this problem,the multi-objective optimization method based on coordinated satisfaction method is used to optimize the design of motor support.Aiming at the conservative design method of the drum of towing engine,the wall thickness of the drum is optimized by using finite element technique and optimization method.(3)The stiffness of the optimized motor bracket is verified by experiments.Simulation method and experimental method are used to verify the optimization results.Based on the similarity theory,a reduced scale model of motor support is designed before and after optimization.The optimized results are verified by micrometer visual measurement method and strain gauge indirect strain measurement method respectively.