地埋管换热器占地面积及钻井费用方案设计

Scheme design of cover areas and drilling cost for ground heat exchanger

常规设计的地埋管换热器会出现埋管占地面积大、钻井费用过高的问题。本文以地埋管常规设计工况为基础,建立地埋管换热器的设计模型,优化换热器的布置形式。结果表明:相比常规布置形式,优化模型可得到较小的埋管间距和埋深,其中:制冷工况下,土壤温度变化量为3~10 K时,对应的最小埋管间距范围为0.7~3.5 m,对应的最小埋深范围为20~110 m;制热工况下,土壤温度变化量为3~10 K时,对应的最小埋管间距范围为0.4~2.0 m,对应的最小埋深范围为5~35 m。通过随机组合埋深及埋管间距进一步优化研究发现:埋深大于25 m时,占地面积小于常规占地面积;埋管间距大于1 m时,钻井总费用的比值都小于1。

The ground heat exchanger with the conventional design usually has large cover area and high drilling cost. Based on the normal design condition of buried-pipe, the design model of ground heat exchanger is established and the layout of heat exchanger is optimized. The results show that compared with the conventional layout form, it can ob-tain smaller buried-pipe spacing and depth in the optimization model. Under the cooling condition, when the soil temperature^ variation is 3 - 10 K, the minimum spacing range is 0.7 - 3.5 m and the minimum depth range is 20-110 m; under the heating condition, when the soil temperature’s variation is 3 - 10 K,the minimum spacing range is 0.4 - 2.0 m9 and the minimum depth range is 5 - 35 m. By combining the buried-pipe depth and spacing randomly to further optimize the study, it’s found that when the buried-pipe depth is greater than 25 m9 the cover area is less than the conventional area; when the buried- pipe spacing is greater than 1 m, the total drilling cost ratio is less than 1.