Study On Methods Of PMP And Short-duration Rainstorm Calculations At Coastal Area

At first, the current situation of Probable Maximum Precipitation and Probable Maximum Precipitation of short duration Calculations research in the world is elaborated in this paper. Then, the computations of PMP in computational means of Local Pattern, Transposition Pattern and the statistical estimate method are elaborated in this paper, taking the PMP of Ningde Nuclear Power Station for example, which are located at the coastal area in the province of Fujian. The Local Pattern includes methods of Enlargement of Vapor Efficiency and Enlargement of Vapor & Wind Speed. 12 rainstorms are chosen as the transposition objects, which took place in the Fujian Province. First, correction of transposition is made after analyse transposition possibility of these 12 rainstorm. Then, by making enlargement of vapor of these 12 rainstorm, the biggest one is taken as PMP of Ningde Nuclear Power Station. Statiscal estimate method is used in the paper. The rainstorm statistical parameter of 12 rain stations near the nuclear power station is analysed. The biggest one is taken to calculate the PMP of Ningde Nuclear Power Station.Frequecy analysis of the maximum 24h precipitation of the year is applied in 12 Rainfall stations which are located at Ningde. The design precipitation with the frequency of 0.01% of these 12 rainfall stations is taken as a basic proof for the rationality of the PMP result.Rainstorm Formula is used in calculatine the Short-duration PMP. In tht paper, with the observed short-duaration rainfalls of the rainfall station around the nuclear power station, parameters of the rainstorm formula is estimated. The short-duration PMP is cacalated by the rainstorm formula.At last, we analyze the rationality for the outcome of PMP and short-duration PMP calculations. The research findings of this paper will provide guidance for the preliminary design of Ninde Nuclear Power Station.