基于浓度响应因子法的建筑物周围污染物扩散快速模拟  

Rapid predrction for pollutant diffusion around buildings with concentration response factor method

作　　者：林一萍 黄弘[1] 吴家麟 张小乐[1] LIN Yiping;HUANG Hong;WU Jialin;ZHANG Xiaole(Institute of Public Safety Research,School of Safety Science,Tsinghua University,Beijing 100084,China;College of Safety Science and Engineering,Nanjing Tech University,Nanjing 211800,China)

机构地区：[1]清华大学安全科学学院,公共安全研究院,北京100084 [2]南京工业大学安全科学与工程学院,南京211800

出　　处：《清华大学学报（自然科学版）》2024年第6期933-939,952,共8页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金项目(72091512)。

摘　　要：浓度响应因子法在稳态流场与固定污染源位置的情况下,能够快速计算污染物释放后浓度变化。该文使用浓度响应因子法对建筑物周围污染物扩散进行模拟,利用典型建筑结构的风洞实验数据验证了该方法的可靠性。通过与计算流体力学(CFD)瞬态模拟方法对比,分析了流场结构、污染物释放函数浓度对响应因子法准确性的影响。结果表明:浓度响应因子法能很好地模拟建筑周边的污染物扩散,浓度的变化趋势与CFD瞬态模拟结果相吻合,FAC2值基本在0.95以上,且能够节约大量求解时间。对于时变的污染源释放函数,浓度响应因子法仍能够很好地模拟过程中任何时刻的浓度。该研究结果可为使用浓度响应因子法快速计算大量建筑周围污染物扩散浓度提供参考。[Objective]To prevent the accidental release of toxic gases in urban environments,it is imperative to measure the concentration field quickly and accurately.The response factor method(RFM)based on the linear response relationship between the sources and the sensors for a steady flow field and a fixed pollution source location yields good results in concentration calculations after pollutant release.It is necessary to convolve the response factor with the release function to calculate the concentration of different pollutant-release conditions.RFM can save considerable calculation time.However,current studies primarily emphasize indoor environments and lack outdoor environment simulations.Thus,we aim to address the problem of using RFM to simulate the concentration when time-varying pollution release occurs around buildings.[Methods]To confirm the reliability of the simulation results,two examples of wind tunnel data(CEDVAL experiment No.A1-5 an isolated building,and No.B1-1 building arrays)were simulated under the same conditions,and the velocity profile results were consistent.RFM consisted of the following steps:(1)The calculation domain was constructed,and the flow field was solved in the steady state.(2)The concentration field under the pulse pollutant release was solved in the transient state,the time series of the concentration response factor was obtained,and the component transfer matrix A represented by the response factor sequence was constructed.(3)The concentration at any time was calculated from the time series of the component transfer matrix A and the release intensity.RFM and computational fluid mechanics(CFD)transient simulation method were employed to simulate three types of pollutant-release scenarios:constant,periodic,and triangular releases.Based on the structural characteristics of the flow field around buildings,sensor positions of different heights and distances were selected for comparison.Next,the RFM and CFD results were compared using the commonly used statistical indexes:fractional bi

关 键 词：浓度响应因子法 大气污染物扩散 建筑物 释放源 

分 类 号：X928.9[环境科学与工程—安全科学]