自然通风与强制通风的空气湿度观测试验评估

Experimental evaluation of air humidity observation of natural ventilation and forced ventilation

自动气象站普遍使用的湿敏电容湿度传感器,因其固有的特性,现有观测规范下,在高湿度段存在较大的观测误差。在标准气象观测场百叶箱环境里,利用强制通风防辐射罩对湿敏电容湿度传感器施加3m/s恒定风速,经过持续两年时间观测,获取强制通风条件下观测的湿度数据和自然通风条件下观测的湿度数据,分别与参考标准器数据进行比较和分析,作为现场动态试验考核评估依据。0%RH～100%RH全量程范围内,强制通风观测对比差值与自然通风观测对比差值相比,平均对比差值仅为自然通风条件下误差的26.7%;90%RH以上高湿段,强制通风平均对比差值为自然通风的54.6%,误差改善接近一半。充分说明,应用强制通风防辐射罩作为湿敏电容湿度传感器的辅助仪器对减少观测误差是十分有效的。

Humidity sensitive capacitive humidity sensors are widely used in automatic weather stations.Due to their inherent characteristics,there is a large observation error in the high humidity section under the existing observation standards.In the standard meteorological observation field Louver box environment,use of forced ventilation radiation shield of humidity sensor capacitor applying constant velocity of 3 m/s,after two years continuous observation data acquisition,humidity observation under the condition of forced ventilation and natural ventilation and humidity data observation conditions were analyzed and compared with the reference standard the data,as the field dynamic test evaluation basis.0% RH to 100% RH full range,forced ventilation and natural ventilation observation observation comparison difference comparison difference compared to the average difference is only under the condition of natural ventilation error 26.7% ;90% RH high above the wet period,forced ventilation and natural ventilation for the average difference of 54.6% ,nearly half of improved error.It is fully explained that it is very effective to reduce the observation error by using the forced ventilation radiation shield as the auxiliary instrument of humidity sensitive capacitive humidity sensor.