Sensitivity Analysis of Hydrogen Source during Severe Accident Induced by Large LOCA for NPP

The hydrogen source,which generates through oxidation of Zircaloy by steam and molten core concrete interaction in cavity,during the severe accident induced by large LOCA for the 600MW NPP was analyzed in this paper by using MELCOR code,including the sensitivity impacts of the different break sizes and locations.The results are summarized as follows: during the large LOCA severe accident,it has no substantial effect on hydrogen source with a different break size;when there is the same break size,the hydrogen generation rate peaks when the break locates in a hot leg;and the total cumulative hydrogen production peaks when the break locates in a cold leg.