Evaluation of Pressure-Temperature Limit Curve for the Safe Operation of an RFV based on 3-D Finite Element Analyses

유한요소해석을 이용한 원자로용기 압력-온도 한계곡선의 평가

  • Published : 2001.10.01


In order to operate an RPV safely it is necessary to keep the pressure-temperature (P-T) limit during the heatup and cooldown process. While the ASME Code provides the P-T limit curve for safe operation, this limit curve has been prepared under conservative assumptions In this paper the effects of conservative assumptions involved in the P-T limit curve specified in the ASME Code Sec. XI were investigated. Three different parameters the crack depth the cladding thickness and the cooling rate, were reviewed based on 3-D finite element analyses. Also the constraint effect on P-T limit curve generation was investigated based on J- T approach. It was shown that the crack depth and the constraint effect change the safe region in P-T limit curve significantly Therefore it is recommended to prepare a more precise P-T limit curve based on finite element analysis to obtain P-T limit for safe operation of an RPV.


P-T Limit Curve;ASME Code Sec. XI;Stress Intensity Factor;J-T Analysis;Constraint Effect


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