Application of Radar Precipitation Data on Rainfall Runoff Model

• Main Authors: Jen-Chieh Cheng, 鄭仁傑
• Other Authors: I Tsou
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/01285119220140442349

碩士 === 國立屏東科技大學 === 土木工程系所 === 98 === The objective of this study is to apply HEC-HMS rainfall-runoff model on 16 major sub basins of Donggang River watershed. The peak discharge of Donggang River is analyzed by the real-time gauged precipitation data and the radar precipitation data. Each rain gauge station of the real-time rainfall data is distributed to each sub basin by Thiessen method in HEC-HMS model. Initial and, constant rate loss module and recession module are used in HEC-HMS. Moreover, the rainfall is transformed into runoff hydrograph by Clark's unit hydrograph method. Radar rainfall is converted to the rainfall data format in HEC-HMS by using Geography Information System and HEC-DSS model to analyse the discharge difference of the same typhoon event in HEC-HMS model. Further more by changing the number of gauge stations to meet the results of runoff hydrograph simulating by radar rainfall data, one can understand the effecenay of gauge station distribution of Donggang River Basin. The result reveal that, for Sepat Typhoon, without adjust the model parameters the average error of peak discharge is approximately 11.8% after adjusted parameters the average error could reduce to 3.9%. Also the result show that, for Phoenix Typhoon, without adjust the parameters the average error of peak discharge 2.7% after adjusted the parameters the number could reduce to 0.6%. But the difference of average error of total flow volume is quite small between unadjust and adjust the model parameters, for both Sepat and Phoenix Typhoon. The study is set up a procedure to establish the parameters range for HEC-HMS by using the gauge rainfall data and radar rainfall data. And the study also provide the possibility of further application on radar rainfall runoff model in the future. The gauge station number will affect the runoff hydrograph result. The model reveal that using five gauge stations to distribute the rainfall in Donggang River Basin, the result hydrograph is more close to the radar runoff hydrograph than using other number of gauge station. The result show that the current gauge station distribution is enough for Donggang River Basin.