A COMPARISON BETWEEN THE FINITE-ELEMENT AND FREQUENCY-RESPONSE METHODS IN THE ASSESSMENT OF THERMAL STRIPING DAMAGE

When incompletely mixed, hot and cold fluid streams pass adjacent to t he surface of a component or structure, and cause thermal striping on the surface. The existing methods of assessment of the consequent ther mal fatigue damage have been implemented in the computer codes CLOUDBU RST, TBL and STRIPE, and these have been shown to be in good agreement . Analysis of temporally random striping is possible in two of the met hods, whereas use of the finite element method in such a fatigue analy sis may lead to impractically long run times. However, for the special case of sinusoidal patterns of striping, comparison is made in this p aper between TBL and the finite element method for the assessment of t hermal striping damage. A fully restrained, single edge cracked plate and a circumferentially cracked cylinder, axially restrained and unres trained, have been subjected to sinusoidal surface striping for variou s representative temporal frequencies. The resulting stress intensity factor fluctuations have been determined for various crack depths usin g the finite element computer code ABAQUS and the analytical code TBL. Good comparisons have been obtained in all cases. (C) 1998 Elsevier S cience Limited. All rights reserved.