突发水污染事故后,高效准确模拟预测是快速采取有效防控措施和制定应急预案的基础。采用基于非均匀网格的图形处理器(graphics processing unit,GPU)加速的水动力及污染物输移数值模型(GPU accelerated surface water flow and associat...突发水污染事故后,高效准确模拟预测是快速采取有效防控措施和制定应急预案的基础。采用基于非均匀网格的图形处理器(graphics processing unit,GPU)加速的水动力及污染物输移数值模型(GPU accelerated surface water flow and associated transport,GAST)对暴雨山洪或溃坝洪水引起的突发水污染事故中污染物输移规律进行了模拟预测。模型采用Godunov格式的有限体积法求解二维浅水方程和污染物输移方程,采用一种基于HLLC(Harten-Lax-Van Leer-contact)的近似黎曼求解器计算单元网格界面通量,采用二阶高精度格式(monotonic upstream-centred scheme for conservation laws,MUSCL)限坡线性重建和龙格-库塔时间积分法实现了二阶精度,同时采用GPU加速计算技术提高模型计算效率。算例结果表明:采用非均匀网格技术局部细化地形复杂区域生成精细网格,地势平坦区域粗化网格,大幅度减少了计算域网格数量,并且在保证模拟精度的同时,提升了模型计算效率。该模型可高效准确地模拟突发水污染事件中污染物输移过程,适用于大规模水污染事故的快速预警和评估。展开更多
Abstract Karst areas have much higher ecological vulnerability and are easy to be contaminated by polychlorinated biphenyls(PCBs) which are introduced as health risk pollutants.PCBs concentrations were used to underst...Abstract Karst areas have much higher ecological vulnerability and are easy to be contaminated by polychlorinated biphenyls(PCBs) which are introduced as health risk pollutants.PCBs concentrations were used to understand the transport behavior of PCBs conducted in the karst Nanshan Underground River,China.Water and sediments from the underground river water,and sediments and soil from the surface of the corresponding watershed were collected monthly in 2011 and 2012 and PCBs were analyzed.Seasonal variations were found in concentrations of PCBs both in the waters and sediments.PCBs concentrations varied from 0.3 to 29.9 ng·L-1 in the groundwater,while from 0.1 to 366.1 ng·g-1 in the underground sediments.Correlations were found in concentrations of PCBs in waters and sediments between the underground river and surface systems which indicate that the surface systems play a major role for the transport of PCBs and contamination in the underground river systems.Karst features are liable for the transport behavior.The underground river waters transport PCBs at mean 3 g·day-1.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.41172331)the Academician Foundation of Chongqing(CSTC,2010BC7004)Geological survey project of Ministry of Land and Resources of China(1212011087119)
文摘Abstract Karst areas have much higher ecological vulnerability and are easy to be contaminated by polychlorinated biphenyls(PCBs) which are introduced as health risk pollutants.PCBs concentrations were used to understand the transport behavior of PCBs conducted in the karst Nanshan Underground River,China.Water and sediments from the underground river water,and sediments and soil from the surface of the corresponding watershed were collected monthly in 2011 and 2012 and PCBs were analyzed.Seasonal variations were found in concentrations of PCBs both in the waters and sediments.PCBs concentrations varied from 0.3 to 29.9 ng·L-1 in the groundwater,while from 0.1 to 366.1 ng·g-1 in the underground sediments.Correlations were found in concentrations of PCBs in waters and sediments between the underground river and surface systems which indicate that the surface systems play a major role for the transport of PCBs and contamination in the underground river systems.Karst features are liable for the transport behavior.The underground river waters transport PCBs at mean 3 g·day-1.
