摘要
在夏热冬暖的广州地区搭建了两种换热器向土壤放热的实验台,换热器埋地深度为30m,实验元件有单U和双U两种型式。连续制冷工况下,通过对两口井内土壤温度变化的研究,结果发现,开机12h后,土壤温度趋于稳定;停机12h后两个埋地换热管处的土壤温度就可恢复约95%,但土壤温度基本得以恢复需要停机81h。在停机12h后地温恢复得极其缓慢,已没有工程应用价值。可见合理选择运行与停机时间有助于提升系统的整体换热能力和地热的综合利用率。通过实验研究发现,间歇工况下双U井单位井深换热量较之连续运行提高了25.6%,单U井单位井深换热量提高了21.8%。
An experimental system with two kinds of heat exchangers was founded in Guangzhou where it is cool in winter and hot in summer. The tested heat exchangers, single U and double U, were embedded in two wells, respectively, whose depth all were 30m. In continuous cooling operation, it was found that the soil temperature increase of soil became little after the unit ran for 12 hours. However, the soil temperature dropped close to its original value after the unit stopped 81h. But it just needed 12 hours for the soil to come back to 95% of its original value. The investigation shows only the initial period of time for unit to shut down is valuable in engineering. In addition, heat transfer performance of unit depth of well of the two embedded heat-exchangers were compared when unit operated in intermittent and continuous cooling operation., single U can increase capability 25.6%, and double U increase 21.8%.
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2009年第10期1373-1377,共5页
Acta Energiae Solaris Sinica
关键词
土壤源热泵
间歇工况
双u
单u
温度响应
soil-souree heat pump
intermittent operation
double U
single U
temperature restorative characteristics
