烟草实验室恒温恒湿机送回风气流方式的改进

Improvement on airflow mode of air supply and return for constant temperature and humidity air-conditioning unit in tobacco laboratory

环境温湿度的波动性对烟草实验室检测设备及测试结果的准确性有重要影响。本文对某烟草实验室温湿度波动度、空气流速、噪声等参数无法达标的原因进行分析,对实验室恒温恒湿机的送回风气流方式进行改进:由散流器送风改为孔板送风,并设计制作静压室,降低风速和噪声。改进后,实验室温度短时波动度由原来的2.5℃降为0.9℃,相对湿度短时波动度由原来的5.6%降为2.2%,空气流速由原来的0.8 m/s降为0.2 m/s,噪声由原来的65 dB(A)降为54 dB(A),达到标准要求。

The fluctuation of ambient temperature and humidity has an important impact on the accuracy of the testing devices and testing results in tobacco laboratories. The reasons why the temperature and humidity fluctuation, the air velocity and the noise in one tobacco laboratory can＇t meet the standard are analyzed. The airflow mode of air supply and return for constant temperature and humidity air-conditioning unit in the tobacco labo- ratory is improved based on analysis, including using perforated ceiling air supply instead of diffuser,adding a plenum chamber to decrease the air velocity and noise. After improve- ment, the short-term fluctuation rate of the temperature and the relative humidity reduces from 2.5 ℃ to 0.9℃ and from 5.6% to 2.2% respectively. The air velocity decreases from 0.8 m/s to 0.2 m/s and noise decreases from 65 dB（A） to 54 dB（A）. As a result,all above parameters meet the lab standard.