水平风作用下火羽流的质量流率

摘要

A model predicting mass flow rate of plume under horizontal wind based on the theory of plume and jet in cross flow is proposed. In this model, the plume is separated into three regions, which are core potential flow region, plume bending region and throughout uniflow region. Cross section of plume is assumed to be circular under wind, and its diameter is the exponential function of height. Dimensional analysis is adopted to obtain the theoretical formula of mass flow rate of plume under horizontal wind, and CFD simulations are carried out to determine the values of parameters in the formula. Expression of mass flow rate of plume under horizontal wind established in this paper is recommended to be used in engineering practice.%在理想羽流和横流中射流思想的基础上,考虑水平风的影响,提出一个预测有风条件下羽流质量流率的理论模型.模型把羽流发展分成势流核心区、羽流弯曲段和顺流贯穿段3段,并假设有风条件下羽流截面形状仍然为圆形,垂直方向上横截面尺寸(半径)与高度为指数函数关系.采用量纲分析,获得水平风作用下非受限空间羽流质量流率理论公式,通过CFD方法进行数值模拟确定理论公式中的待定参数,得到可方便应用于工程实践的质量流率最终表达式.