Background: In nuclear plant vapor explosion analysis

fuel drop diameter is an important parameter which could significantly influence the evaluation of explosion pressure.Purpose: Decrease the uncertainty of vapor explosion calculation caused by fuel drop diameter.Methods: A simulation model of typical vapor explosion was built using MC3D to take sensitive analysis of fuel drop diameter.Results: The calculation relates to fuel drop energy

fuel drop fragmentation rate and vapor explosion pressure.The effect of fuel drop diameter in vapor explosion is analyzed based on theoretical analysis and the calculation.Conclusions: The results show that the vapor explosion pressure is very sensitive to fuel drop diameter

which is mainly caused by the fuel drop energy and the fuel drop fragmentation rate.