The analysis of RAMP effect for PCMI

The purpose of this paper is to study the effect of RAMP rate on cladding stress, and to provide a basis for PCMI. By selecting the effective stress of cladding as the index. the trend of the change of cladding stress corresponding to the change of RAMP is summarized with the simulated operating conditions (by RoPE) and relevant experiments. The results show that with the increase of RAMP rate, the maximum effective stress grows correspondingly; however, when the rate is more than 10 kW·m^-1·min^-1 the stress tends to be saturated. This rule meets the results of thermal analysis. Consequently, it is reasonable to adopt this RAMP rate in PCMI analysis and testing. (author)