Remaining life of a vessel containing an internal corner crack under repeated thermal shock

Abstract

The remaining life for a hypothetical pressure vessel containing a defect which is subject to thermal shock has been calculated. Twelve cases of thermal shock loads of different severity characterized by the dimensionless parameters, Biot (B) and Fourier (F) numbers, were analysed by finite element modelling (FEM). The estimation of remaining life for each case was carried out based on the PD6493 defect assessment procedure (1). The effect of thermal shock on the crack growth rate was quantified showing that more severe shocks accelerate crack growth while less severe shocks may lead to slow growth or eventual crack arrest.

Keywords

thermal shock thermal transient stress Fourier number Biot number failure assessment diagram remaining life crack growth

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References

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