Computational study of pitting defect influence on mesh stiffness for straight beveloid gear

Abstract

As the representation for the effects of contact and bending elasticity gear tooth, variational mesh stiffness is an important source of excitation for gear vibration. Aiming to get the numerical method of calculating mesh stiffness of the irregular taperred tooth profile, an efficient slice-based mesh stiffness modeling method is introduced for straight beveloid gear pair with and without the pitting corrosion defect. The deformation for tooth fillet and transient curve part are considered to improve the calculation accuracy. The FEM model is used to verify the results obtained by the proposed model and showed that the peak error is only 3.2%. Then the effects of different sizes and locations of pitting defects are analyzed. Results show that the size of pitting defect is a significant influencing factor for mesh stiffness. The mesh stiffness is reduced by 28.3% as the radius of pitting defect increases from 1 mm to 5 mm. For the impacts of pitting defect locations, the mesh stiffness has a noticeable fluctuation when the pitting defect is close to tooth root. While the pitting defect is shfited from root to a certain height, the mean mesh stiffness is decreased by 2.2% and the fluctuating value is decreased by 24.6%.The distance between pitting corrosion center and transverse plane has a little influence on the mesh stiffness.