Showing 2 results for Masoudi Nejad
S.m Salehi, G.h. Farrahi, R. Masoudi Nejad,
Volume 1, Issue 1 (6-2014)
Abstract
This paper presents the prediction of fatigue life and crack propagation in the railway wheel due to the stress field caused by mechanical loads and press fitting process of a railway wheel. A 3-D nonlinear stress analysis model has been applied to estimate stress fields of the railway wheel in press fitting process. Finite element analysis model is presented applying the elastic–plastic finite element analysis for the rail wheel under contact mechanical loads. Calculative analysis applying a finite element method (FEM) has been used to predict residual stresses. Then the stress history is used to calculate stress intensity factor (SIF) and fatigue life of railway wheel under service conditions. The effect of several parameters, vertical loads, initial crack length and friction coefficient between rim and hub/wheel, on the fatigue life in railway wheels is investigated using the suggested 3-D finite element model.
Reza Masoudi Nejad, S.m. Salehi, Gholam Hossein Farrahi,
Volume 2, Issue 2 (11-2015)
Abstract
One of the most important issues in railroad wheels is residual stresses. It is desirable to produce less residual stresses when possible and to decrease the remaining residual stresses in the wheels. The goal of this paper is to predict the crack propagation detail in a railroad mono-block wheel in the presence of residual stress induced by manufacturing process and service conditions. A 3-D elastic-plastic finite element analysis, using the ANSYS/PDS tool is used to estimate the residual stress field and also the superposed alternating rolling contact stresses in a mono-block wheel. A three-dimensional finite element procedure is developed for analyzing fatigue crack growth in the wheels by using Franc3D software. Fracture mechanics is used to predict the crack growth life developed from a two-stage fatigue loading cycle where both mechanical loads and thermal loads are present. The results revealed that crack growth life is highly sensitive to the residual stress. Therefore, this factor significantly affects the crack growth life of railroad wheels during service conditions. In the present investigation, a number of parameters such as the axle load, crack size and coefficient of friction are studied using the proposed model.
