温室地下蓄热系统换热管道流速分布与蓄热性能研究

Study on the distribution of airflow velocity within heat exchange pipes and heat saving performance of the underground heat storage system in greenhouse.

基于作物幼苗期对气温与土壤温度的要求,设计了一种新型地下蓄热系统,对影响换热管道内热量交换的主要因素——空气流速进行测试.结果表明,空气流量在各换热管道内分布均匀,且管内空气流动呈紊流状态,有利于增强空气与管壁间的对流传热;理论分析可知,该蓄热系统能够贮存大量热能,且蓄热量大于其消耗的电能,节能效果明显.

According to the air and soil temperature requirement of crops at seedling stage, a new underground heat storage system to be used in greenhouse was designed. As a key factor of heat exchange, distribution of airflow velocity in the heat exchange pipes was measured. The results indicated that air flux was evenly distributed and the flowing air in every heat exchange pipe was in a turbulence state, thus enhancing heat convection between the air and pipe walls. It is also shown from theoretical analysis that the heat saved was more than the electric energy consumed in the system, and the effect of energy saving was significant.