MSIV COMPARTMENT PRESSURE RESPONSE TO MSLB WITH TMD CODE

摘要

A large number of investigations on the in-containment compartment pressure response to a pipe break have been done up to now. However, there are still a few researches into the pressure response of compartments outside containment. In this paper, the Transient Mass Distribution (TMD) code is used to analyze the pressure response of AP1000 Main Steamline Isolation Valve (MSIV) compartment outside containment to Main Steamline Break (MSLB). Effects of various parameters, such as environment temperature, entrainment and break location, on the pressure response of AP1000 MSIV compartment outside containment to MSLB are investigated. It is shown that, as the environment temperature increases, the maximum differential pressure occurs during the transient increases, while the peak pressure occurs during the transient decreases from 30℃ to 60 ℃. As the entrainment increases, the maximum differential pressure happens during the transient increases, and the peak pressure happens during the transient increases in the range of 0% to 30%, while decreasing in the scope of 30% to 100%. Comparing with MSLB in the lower west MSIV compartment, the maximum differential pressure and the peak pressure take place during the transient are larger for MSLB in the lower east MSIV compartment. During the transient, the peak pressure appears in the breaking node, and the maximum differential pressure occurs between the breaking node and the atmosphere node.