微环境新风量的检测原理及方法研究

新风量是评价室内微环境空气卫生质量的主要卫生指标之一，也是计算室内某种气体单位时间排放量的重要参数。以CO2作为示踪气体，利用于冰升华和人体呼吸产生CO2示踪气体两种测量方法对室内和车内微环境进行了检测，并考虑室内人呼出CO2量的影响，运用箱子模式的各种推导公式（稳态法、解析解法和差分法）对新风量进行了计算，并对结果进行了讨论。结果表明，没有人存在下，用箱子模式的解析解法和差分法计算的新风量值没有明显的统计差异；微环境内有人时必须考虑人释放的影响，这样箱子模式的各种推导公式都可以计算新风量值，且结果准确，准确度高。利用人体呼吸产生CO2示踪气体法，用差分法计算结果不理想，偏差很大；用稳态法计算重现性高，结果可靠。

Monitoring principle and methodology for air change flow in indoor air

Air change flow is one of the sanitarian standards which can evaluate indoor environmental quality,and it is also one of the important parameters that may calculate gas discharge amount per unit time.This experiment uses carbon dioxide as the tracer gas,which comes from dry ice sublimation or human breathing,to examine air change flow of indoor and in-vehicle microenvironent.For human breathing,the indoor air change flow is calculated by using derivation formulae(steady-state method,analytic solution and difference method) from box model. Preliminary results indicate that air change flow,which is calculated by analytic solution and difference method,has no significant statistical difference without people inside microenvironment.When human breathing impact must be considered with people inside microenvironment,all the derivation formulae could be used to calculate air change flow.In this case the results are credible and the accuracy is high.Using carbon dioxide from human breathing as the tracer gas,the difference method is not ideal and the result windage is high,while the steaty-state method is credible and the reproductivity is good.