基于教室舒适性的送风参数寻优及感染风险分析

Optimization of Air Supply Parameters and Infection Risk Analysis Based on Classroom Thermal Comfort

针对当前部分教学楼教室无法满足人体热舒适要求和教室内人员分布较为密集,若存在感染者其感染风险未知等问题,采用计算流体力学软件(CFD)模拟了不同工况的送风参数下(改变送风速度、送风角度)教室内的气流组织及热舒适性,应用熵权法对热舒适指标PMV和吹风不满意率DR进行赋权,应用多目标优化TOPSIS法对不同工况进行排序,得出在送风温度为18℃下的最佳送风参数组合为:送风速度为1 m/s,送风角度为60°。该工况下工作区热舒适指标PMV和吹风不满意率DR平均值为0.827和0.326,并针对此工况运用改进的感染风险模型进行感染风险预测,发现感染者呼出的飞沫大部分聚集在教室左侧区域,故此区域内感染风险较高。

Currently, some classrooms in academic buildings cannot meet the requirements of human thermal comfort and the distribution of people in classrooms is relatively dense, the risk of infection is unknown if there are infected people, so the Computational Fluid Dynamics(CFD) is utilized to simulate the air distribution and thermal comfort in the classroom under different air supply parameters(changing the speed of air supply and angle of air supply), and the entropy weighting method is applied to assign weights to the thermal comfort index PMV and air blowing dissatisfaction rate DR, and the multi-objective optimization TOPSIS method is applied to rank different working conditions, the optimal combination of air supply parameters at a supply air temperature of 18 ℃ is obtained as follows: while the air supply speed is 1m/s, and air supply Angle is 60°, the mean values of PMV and DR are 0.827 and 0.326. An improved infection risk model is applied to predict the infection risk for this working condition, and it is found that most of the droplets exhaled by infected persons gathered in the left area of the classroom, so the infection risk in this area is higher.