地热采暖工况下地板散发的污染物分布研究

Study on the distribution of pollutants emitted from the floor under geothermal heating conditions

利用自制环境舱模拟北方寒区地热式采暖工况,采用AirPak数值模拟软件模拟不同采暖温度下气候舱内部的气流组织,分析各特征点处的速度值和温度值,并对甲醛散发特性及浓度进行研究。研究结果表明:在22℃、26℃、30℃三个温度下,气候舱室内部轴心处的气流速度分布都呈现出相同的趋势。当温度上升到30℃时,气候舱轴线处气流速度最高。在轴心处气流的温度梯度分层不是很明显,靠近地板附近的温度稍高,整个舱室竖直方向上的温度比较均匀。温度为22℃时,舱室内甲醛浓度波动不大。舱室内温度为26℃和30℃时,甲醛浓度波动较大。温度为30℃时,舱室上端采样口处测得的甲醛浓度高于下端采样口处的浓度,且两个采样点处甲醛浓度水平差异较大。

The self-made climate chamber was used to simulate the geothermal heating conditions in the cold regions of the north.The AirPak numerical simulation software was used to simulate the airflow organization in the climate chamber under different heating temperatures.The velocity and temperature values at each characteristic point were analyzed,and the characteristics and concentration of formaldehyde emission were analyzed.The results indicate that the distribution of air velocity at the axis inside the climate chamber showed the same trend at the temperature of 22℃,26℃and 30℃.When the temperature rose to 30℃,the air velocity at the axis of the climate chamber was the highest.The temperature gradient stratification of the airflow at the axis is not obvious,the temperature near the floor is slightly higher,and the temperature in the entire cabin is relatively uniform in the vertical direction.When the temperature was 22℃,the formaldehyde concentration in the cabin fluctuated little.When the temperature was 26℃and 30℃,the concentration of formaldehyde fluctuated greatly.At the temperature of 30℃,the formaldehyde concentration measured at the upper sampling port of the cabin was higher than that at the lower sampling port,and the difference in the concentration of formaldehyde at the two sampling points was large.