AHMET N. ERASLAN, YASEMİNKAYA, BÜŞRAÇİFTÇİ

A COMPUTATIONAL MODEL FOR PARTIALLY-PLASTIC STRESS ANALYSIS OF ORTHOTROPIC VARIABLE THICKNESS DISKS SUBJECTED TO EXTERNAL PRESSURE

A computational model is developed to predict the states of stressand deformation in partially plastic, orthotropic, variable thickness, nonisothermal, stationary annular disks under external pressure. Assuming a state ofplane stress and using basic equations of mechanics of a disk, Maxwell relation,Hill’s quadratic yield condition, and a Swift type nonlinear hardening law, asingle governing differential equation describing the elastic and partially plasticresponse of an orthotropic, variable thickness, nonisothermal disk is obtained.The solution of this nonlinear second order differential equation subject to freeand pressurized boundary conditions is achieved by a shooting method. In thisarticle, we move towards the governing equation by going through basic equations that lead to it and present its solution procedure and some interestingresults

Keywords:

Orthotropic disk, Variable thickness Elastoplasticity, Hill’s quadraticyield criterion, Shooting method,

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Department of Engineering Sciences, Middle East Technical University, 06800, Ankara- TURKEY
E-mail address: aeraslan@metu.edu.tr , kyasemin@metu.edu.tr , bciftci@metu.edu.tr