Qatar and Saudi Arabia both had double-digit decreases in project numbers.
卡塔尔和沙特阿拉伯在项目数量上都出现了两位数的下降。
When double and multi-U-tube ground heat exchangers are used, heat transfers of the system decreases due to the thermal disturbance among the tubes.
双管和多管布置时,由于管间的热干扰作用,系统的换热量将不同程度降低。
应用推荐