Gear Modification Based On Finite Element Method

With the development of wind turbine generation to higher power, the gear box has been put forward higher requirements. There are many problems such as high failure rate, high vibration and noise, long life and so on,nowadays. The technology of gear modification has been proved to be an effective method for reducing the vibration and noise of gear box and prolonging the life of gear box. Therefore, we have a great significance for the study of the tooth profile of the wind turbine gear box.This paper combines with the previous tooth profile modification technology,tooth profile modification design method and finite element analysis. Besides, it can provide a new gear modification design technology based on finite element method,to provide technical support for the development of more advanced wind turbine.First of all, according to the gear meshing principle, according to the principle of involute gear meshing involute the equations of the dedendum transition curve and the coincidence degree, in the classic ANSYS interface. And then, Using APDL programming to establish the 3D parametric finite element analysis model of gear,and complete the mesh refinement of the contact elements.Then, the file is imported into Hypermesh to remove its geometric elements, and the CDB file only containing the node and element information is derived as a repair object. In the Workbench ANSYS, the gear material properties, constraints, speed,output shaft resistance torque and gravity loads are added.According to the analysis results of dynamics, the elastic deformation of the contact area and the stress distribution of the tooth surface are obtained. By the data obtained, the stiffness values of the single tooth pair and the double teeth pairs are calculated respectively. According to the meshing stiffness、the gear manufacturing precision and elastic deformation of gear’s edges, the gear modification related parameters can be obtained.Finally, according to the obtained parameters, combined with APDLprogramming, the tooth profile modification design of the tooth surface can be accomplished automatically and quickly.The analysis results show that the stress reduction, the amplitude of the stress of tooth surface is decreased, the gear life is increased, and the reliability is increased,after the tooth profile modification.