بررسي كارآيي روش همگن سازي غيرعددي (منحني هاي اندرو) در برآورد سيل

Study on efficiency of non numerical (Andrew curve) method in determination of homogeneous area in flood estimation

There are many ways to transfer data gauged watersheds to un-gauged which all is based on geographical vicinity whereas it is not the only necessity for the same. In the present study, 20 stations having a reliable and a lengthy data were selected and their data were analyzed to find out discharge values with 2, 5, 10, 25, 50 and 100 years return period. In continuation 5 physiographical and 3 climatological parameters were extracted among which area and mean height were found to he more important parameters using factor analysis. The selected watersheds were then classified into 5 groups. The instantaneous discharge values were then estimated for each station situated in the same group and finally the error of estimations were calculated. The results of the study revealed that the efficiency of applied Andrew curve can not be finalized because of different values of error respectively equal to 174, 18, 156, 181 and 50 percent for the homogenous area 1 to 5.