报告人： Prof. Padraic O’Donoghue （National University of Ireland, Galway）

时  间：2013年10月31日9:30-11:00

地  点：304永利登录入口水院楼101

联系人：剧锦三教授；电话: 62737130

报告摘要

Finite Element Modelling of the Thermo-mechanical Behaviour of Power Plant Steels

Padraic O’Donoghue

National University of Ireland, Galway

　　As a result of the ever changing landscape of the power generation industry, fossil-fuel based power plant need to operate with increased flexibility. This change is driven by (i) a requirement to reduce emissions from fossil fuel plant, (ii) the control of energy costs by continuous mixing of energy sources and (iii) the intermittent nature of renewable energy. Therefore the complex operational cycles, which current and future plant must endure, lead to thermo-mechanical fatigue (TMF) and creep-fatigue (CF) failure. This dictates the requirement for an advanced materials capability with flexible loading and accurate life prediction for next generation power plants.

　　A hyperbolic sine unified viscoplastic material model is presented to model the cyclic behaviour of materials under high temperature loading. The material model is developed from a thermodynamic framework and is implemented in multi-axial form within a user material subroutine. The user material subroutine is calibrated and validated for P91 steel across a range of cyclic (isothermal fatigue and thermo-mechanical fatigue) and non-cyclic high temperature loading conditions. A novel method for the identification of the cyclic viscoplastic material parameters is presented and the results indicate that the material model is capable of capturing the complex constitutive behaviour of 9Cr steels across a wide range of stress, as well as simulating the strain rate and anisothermal effects observed in such materials.

教授简介

About Padraic O’Donoghue

An engineer and an educator, Padraic O’Donoghue has held academic positions at Irish universities for more than twenty years. He holds a B.E. in Civil Engineering and an MSc in Applied Mathematics from Ireland.  He pursued doctoral studies at Georgia Institute of Technology, graduating with his Ph.D. in 1985.  He then worked at Southwest Research Institute in San Antonio, Texas for five years.  He returned to Ireland in 1990 to take up a full-time academic position University College Dublin.  In 1997, he was appointed as Professor of Civil Engineering (Chair) at the National University of Ireland, Galway, a position that he still holds.  He expanded his role at NUI Galway when he took on the post of Dean of Engineering and Informatics for a nine year period (2001-2010).  

Professor O’Donoghue has an extensive and varied set of research interests including work on advanced, non-linear computational methods in structural mechanics, particularly finite element methods.  He has specialised in the development of fracture, fatigue and damage mechanics techniques with many noteworthy contributions in the aeronautical and gas pipeline industries. Professor O’Donoghue has published widely, including more than 75 peer reviewed papers in journals and international conferences, in addition to many invited presentations at symposia, workshops and universities around the world.  Professor O’Donoghue has also chaired the organising committees for three prestigious international conferences.  See also: http://www.nuigalway.ie/civileng/Staff/padraicodonoghue.html