Cooperative Optimization Design Of Crank And Connecting Rod Mechanism Of Cylindrical Gear Linkage Hydraulic Engine

Traditional engines’ low efficiency and serious pollution spawn the production of structural principle about Gear-linked cylinders hydraulic engine(GCHE). It uses the pinion-and-rack mechanism to complete motion and power transfer between cylinders. The crankshaft flywheel group is arranged on one side to perform the control of piston stroke and the driving of auxiliary systems. Crankshaft and rod mechanism is the main core part of the dynamic system, in order to achieve the best working condition, it is necessary to optimize the structure design. Multidisciplinary collaborative optimization design must be taken because the single component’s optimization can’t meet the requirements of performance.This paper firstly discusses the structure and working principle of the two-cylinder GCHE and the dynamical analysis, then conduct the structural design requirements, build the structure size parameter optimization model, conduct the Design of Experiment and optimization for rod and crankshaft based on the ISIGHT, then build the collaborative optimization for rod and crankshaft. Establish the collaborative optimization based on the approximation models of rod and crankshaft.Build the design of experiment for rod and crankshaft based on the ISIGHT and ANSYS, the results show that the design variables generate great influence on state variables. Conduct the optimization for rod and crankshaft, the optimization of rod uses the Sequential Quadratic Programming(NLPQL) method, the volume of rod decrease 26.13%, the optimization crankshaft uses the Downhill Simplex(DS) method, the volume decrease 0.96%, and the force distribution be more uniform, the structural be more reasonable. Considering the relationship between rod and crankshaft, build the collaborative optimization model. Conduct the respond surface approximation models of rod and crankshaft, build the collaborative optimization mode base on the approximation models. The total volume decrease 4.49%.Based on response surface approximation model, collaborative optimization can greatly reduce the computational effort, save computational cost and high accuracy, which provides an analytical method for the effective design of the Gear-linked cylinders hydraulic engine’s rod and crankshaft.