Dimensional Optimization of Helical Gear Pair Through Finite Element Analysis Using Subproblem Approximation Method

Abstract

Traditional helical gear stress analysis techniques such as AGMA and ISO standards provides very often over-dimensioned gear pairs with bulky design. Therefore, it is required to optimize the gear pair design using latest techniques like finite element analysis. Stress analysis technique chosen to investigate the feasibility of dimensional optimization of a gear was Finite Element Analysis platform ANSYS 12.1. ISO 6336 standards and Hertz contact theory neglect friction between contact teeth. This work reflects coefficient of friction between contact teeth using FEA predicts more accurate results for contact stress. In this work, case hardened steel helical gear is optimised for optimum tooth root stress level subsequently to reduce the face width of gears with other geometrical parameters unaffected. Efforts has been carried out to verify contact stress value using Lagrange multiplier algorithm of optimised helical gear pair. Subproblem approximation method was implemented for searching of optimal solution of design variable. Optimized gear pair was manufactured and experimentally investigated for actual stresses and strains, as per loading condition mention in the rules of TED. Percentage saving in the material for optimised gear pair also been included in this work.

Keywords: Optimization, Helical Gear, Optimized Gear Stress Analysis, ISO 6336