Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 49 4 2018 02 20 Time-Dependent Analysis and Creep Life Prediction of Rotating Hollow Cylinders using Theta Projection Concept and Larson Miller Parameter Time-Dependent Analysis and Creep Life Prediction of Rotating Hollow Cylinders using Theta Projection Concept and Larson Miller Parameter 673 684 747 10.22060/mej.2016.747 FA H. Mohammadi Hooyeh Department of Solid Mechanics, Faculty of Engineering, University of Eyvanekey, Garmsar, Iran M. Safari Department of Solid Mechanics, Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran A. Loghman Department of Solid Mechanics, Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran Journal Article 2015 10 14 In this work, stresses, strains, creep damage and remnant life for rotating thick walled hollow cylinder made of alloy steel using the theta projection concept and Larson miller parameter are investigated. Loading is composed of internal and external pressure, a distributed temperature field and a centrifugal body force. Using stress-strain, strain-displacement and equilibrium relations a second-order non-homogenous differential equation containing creep strains for radial displacement is obtained. With ignoring amounts of creep strains, thermo-elastic solution of constitutive equation at zero time is achieved. With considered creep strains in mentioned differential equation and differentiating with respect to a time, a differential equation consist of radial and circumferential creep strain rates for radial displacement rate is obtained. By combining theta projection model and Prandtle-Reuss relations and substituting instead strain rates in last differential equation and then numerically solving that, radial displacement rate and stresses are calculated. Using Larson effective stress at each point and Miller parameter and Rabinson's rule, creep damage and remnant life redistributions along the thickness of cylinder are achieved. It has been found that maximum and minimum creep damage is occurred at inner and outer surfaces of cylinder respectively.Also remaining life at outer surface is more than inner surface. In this work, stresses, strains, creep damage and remnant life for rotating thick walled hollow cylinder made of alloy steel using the theta projection concept and Larson miller parameter are investigated. Loading is composed of internal and external pressure, a distributed temperature field and a centrifugal body force. Using stress-strain, strain-displacement and equilibrium relations a second-order non-homogenous differential equation containing creep strains for radial displacement is obtained. With ignoring amounts of creep strains, thermo-elastic solution of constitutive equation at zero time is achieved. With considered creep strains in mentioned differential equation and differentiating with respect to a time, a differential equation consist of radial and circumferential creep strain rates for radial displacement rate is obtained. By combining theta projection model and Prandtle-Reuss relations and substituting instead strain rates in last differential equation and then numerically solving that, radial displacement rate and stresses are calculated. Using Larson effective stress at each point and Miller parameter and Rabinson's rule, creep damage and remnant life redistributions along the thickness of cylinder are achieved. It has been found that maximum and minimum creep damage is occurred at inner and outer surfaces of cylinder respectively.Also remaining life at outer surface is more than inner surface. https://mej.aut.ac.ir/article_747_8d317bdcf4aafcfc22149d77babee96d.pdf