临近流域替代法在巴基斯坦卡洛特水电站坝址洪峰流量预报中的应用

Application of adjacent watershed substitution method in flood peak flow forecast of Karot Hydropower Station in Pakistan

为延长巴基斯坦卡洛特水电站施工期坝址洪水预见期,利用临近流域替代法和API模型估算印控克什米尔地区区间来水,实现卡洛特水电站短期坝址流量预报计算或估算。选取“20170406”“20180420”和“20180807”等3场洪水实测降雨资料和预报降雨资料对该方法的适用性进行验证。结果表明:以上3场洪水实测降雨估算洪峰流量结果与实测洪峰流量最大相对误差均在许可误差的20%内,预报降雨计算结果受预报准确率影响,导致“20180807”洪水计算结果偏小。在获得流域准确降雨预报时,该方法能较好地预估洪峰范围,延长洪水预报预见期,可为卡洛特水电站安全度汛提供技术支撑。

To extend the forecast period of the dam site flood during construction of Karot Hydropower Station in Pakistan,adjacent watershed substitution method and API model were used to estimate the inflow from Indian Kashmir and achieve Karot Hydropower Station short-term dam site flow prediction calculation or estimation.The measured rainfall data and forecast rainfall data of 3 floods,flood number of 20170406,20180420 and 20180807,were selected to verify the applicability of the method.The results show that the maximum relative error between the floods calculated by measured rainfall and the actual flood peak flow for the three floods is within toleranced scope of 20%,and influenced by the rainfall forecast accuracy,the forecasted result of flood 20180807 is smaller.When the accurate rainfall forecast is obtained,the method can forecast the range of flood peak better,extend the forecast period of flood,and provide technical support for the flood control safe of Karot Hydropower Station.