中文摘要：

为了正确预测热污水排放在受纳水域的掺混扩散规律，采用考虑浮力的雷诺应力紊流模型（RSM）对不同排放口长宽比的情况进行了三维紊流数值模拟，应用颗粒成像系统（PIV）和红外热像仪系统测得的热污水表面横向侧排试验流场和温度场作为验证．计算结果和试验结果吻合较好，表明所采用的三维紊流数学模型具有较高的精度．排放口长宽比对热污水表面侧排近区特性有较大的影响，并且扩散宽度和排放口的长宽比具有良好的相关关系．

英文摘要：

In order to study the mixing and diffusing patterns of thermal wastewater in receiving waters, the Reynolds Stress Model （RSM） considering buoyant effects was used to simulate the three-dimensional near-field behavior of thermal wastewater. Measured flow and temperature fields using particle image velocimetry （PIV） system and infrared thermal imaging system were used for model validation. The simula- ted results agree well with the experimental data, indicating that the three-dimensional buoyant model has satisfied precision. The results show that the length-width ratio of discharge outlet has significant effects on the near-field behavior of thermal wastewater, and has good correlation with the diffusion width of thermal wastewater.