北京某高校教室自然通风下新冠感染概率实验和模拟研究

Experimental and simulation study on infection rate of SARS-CoV-2 under natural ventilation in classrooms of a university in Beijing

采用实验和模拟的方法研究了北京某高校教室中学生新冠感染概率的问题。运用Wells-Riley模型计算得出:当量子生成率(quanta值)从14增加到48时,关窗条件下教室人员感染概率从11.22%提高至33.44%,开窗条件下感染概率从5.73%提高至18.37%;换气次数增加至12 h-1时,感染概率为0.51%。利用佩戴口罩模型计算感染概率,关窗条件下不佩戴口罩吸入病毒感染概率为54.79%,佩戴口罩时为13.7%;开窗条件下不佩戴口罩吸入病毒感染概率为29.89%,佩戴口罩时为7.47%。在短时间暴露情况下,关窗条件下佩戴口罩时感染概率降低至23.41%,开窗条件下降低至15.45%,采用机械通风将换气次数增加到5 h-1时,佩戴口罩感染概率降低至0.2%,有效降低了感染概率。

Experimental and simulation methods are used to study the SARS-CoV-2 infection rate of students in classrooms of a university in Beijing.The Wells-Riley model is used to calculate and obtain that when the quantum generation rate(quanta)increases from 14 to 48,the infection rate of classroom personnel increases from 11.22%to 33.44%under window closing condition,and from 5.73%to 18.37%under window opening condition.The infection rate is 0.51%when the air change rate is increased to 12 h-1.Using the wearing mask model to calculate the infection rate,when the window is closed,the infection rate of inhaling the virus is 54.79%without a mask and 13.7%with a mask.When the window is open,the infection rate of inhaling the virus is 29.89%without a mask and 7.47%with a mask.In the case of short exposure,when the mask is worn,the infection rate is reduced to 23.41%under window closing condition and 15.45%under window opening condition,and the infection rate is reduced to 0.2%when the air change rate is increased to 5 h-1 by mechanical ventilation,which effectively reduces the infection rate.