温室地下蓄热系统换热管道空气流速对蓄热效果影响

Effects of Air Velocity in Heat Exchanging Pipes on Heat Saving of the Underground Heat Storage System in Greenhouse

为确定双层覆盖温室地下蓄热系统换热管道空气流速对蓄热增温效果及对温室温度与湿度环境的影响,分别测试了该系统换热管道以不同空气流速蓄热时换热管道进出口空气温度和湿度、地坪温度以及相邻无蓄热系统温室内的气温、土壤温度和室外温度。结果表明,白昼晴朗时,当换热管道内空气以流速0.6、1.0、1.5、2.0、2.5、2.8 m/s进行蓄热时,地坪温度均高于相邻无蓄热系统温室内的土壤温度,平均温差分别为0.8、1.1、3.1、3.9、4.3、5.6℃,系统蓄热效果随换热管道空气流速增加而增强。在系统换热管道内空气流速以0.6~2.8 m/s蓄热时,温室内热空气流经换热管道温度明显降低,使蓄热温室内的气温低于相邻温室气温0.1~0.6℃,但蓄热温室气温在常见温室栽培作物所需的适宜温度范围内,换热管道以不同空气流速蓄热对温室的温度环境影响较小。

The research on effects of air velocity in heat exchanging pipes on heat storage, temperature and humidity in double-film greenhouse with heat storage system was done during heat saving in winter. The temperature and humidity inlet and outlet of heat exchanging pipes, floor temperature in heat storage greenhouse, air temperature and soil temperature in the adjacent reference greenhouse and outside temperature were measured at different air velocities in the heat exchanging pipes. The experiment results show that the average floor temperature in heat storage greenhouse was respectively 0.8, 1.1, 3.1, 3.9, 4.3 and 5.6℃ higher than that of the soil in the reference greenhouse when the air velocity in heat exchanging pipes was 0.6, 1.0, 1.5, 2.0, 2.5 and 2.8m/s in clear day. While the air velocity in heat exchanging pipes was 0.6-2.8 m/s, the air temperature in the heat storage greenhouse was 0.1- 0.6℃ lower than that of the reference greenhouse because the hot air temperature was reduced after flowing through the heat exchanging pipes. However the air temperature in heat storage greenhouse was feasible for plant growth during heat saving.