冰湖溃决洪水演进模拟

Abstract

以西藏年楚河流域的典型危险性冰湖——黄湖及其下游区域为研究对象，采用二维溃坝洪水演进数值模型，进行了模型的率定和不同工况下的洪水演进模拟。设置了瞬时全部溃决和逐渐溃决2种工况，模拟结果表明：洪水发生后，预计最大淹没面积约为89.25 km2，溃决洪水到达江孜的时间约为33.6 h，江孜处的洪峰流量约为1777 m3/s，大于江孜地区暴雨洪水万年一遇洪峰流量1000 m3/s。根据预测结果做好预警工作，能一定程度上减小灾害损失。本研究的研究结果对于完善江孜地区的潜在危险冰湖数据库和科学制定洪水预警策略具有重要的现实意义。 The typical dangerous glacial lake—Huanghu and relevant region, located in Nianchu River Basin, Tibet, China were selected as the study area for this paper. A two-dimensional dam-break flood numerical model was used to calibrate the parameters of the model and simulate outburst flood evolution under different breach mechanisms. The result showed that the largest inundated area was 89.25 km2, the arrival time of flood in Gyantse was about 33.6 h and the peak discharge in Gyantse was about 1777 m3/s. The peak flow of storm flood was 1000 m3/s. The results have im-portant practical significance to improve the potentially dangerous glacial lakes databases of Gyantse and develop flood warning strategies scientifically.