多年冻土区路基用太阳能吸附式制冷管的试验研究

Experimental Study on Solar Adsorption Refrigeration Tube for Subgrade Engineering in Permafrost Regions

针对中国多年冻土区广泛面临的冻土退化和路基融沉问题,提出引入一种更具实时性和有效性的防治方法——制冷技术。应用理念为,通过制冷技术在暖季将热量由多年冻土逆向传递回大气环境,实时控制冻土的热量收支状态。对于制冷驱动源的分散供应,中国多年冻土区属于太阳能利用条件良好的Ⅰ类地区,太阳能制冷技术面向冻土保护具有季节匹配性、地域匹配性和技术匹配性等方面的适用性。设计与制作一种路基专用吸附式制冷管,包括集热/吸附段、冷凝段、蒸发制冷段等部分。装置工作原理为通过太阳能光热驱动吸附式制冷循环,以活性炭和甲醇为制冷工质对,利用太阳辐射的昼夜交替特征实现间歇式制冷。制冷性能试验表明,装置的制冷温度可达-2.9℃,平均温度为-1.5℃,可以有效地保护多年冻土。

In order to improve the permafrost degradation and thawing settlement of the subgrade in permafrost regions,the refrigeration technology was introduced to protect the permafrost in a more timely and effective way.The refrigeration can realize the reverse heat transfer from permafrost to atmosphere in warm season,and consequently control the heat budget of permafrost in real time.China’s permafrost regions are the ClassⅠareas with good solar energy utilization conditions.Solar refrigeration technology has the applicability of seasonal matching,regional matching and technical matching for permafrost protection,which can address the diversified supply of driving force for refrigeration.A novel solar adsorption refrigeration tube for the subgrade was designed and manufactured,whose components mainly include solar heat-collection/adsorption section,condensation section and evaporative refrigeration section.The proposed solar refrigeration tube can act as an integrated energy conversion unit with both solar heat-collecting function and heat-driven refrigeration function.The operational principle is to drive the adsorption refrigeration by solar photothermal technology.The refrigeration tube,using activated carbon and methanol as refrigerant pairs,realizes intermittent refrigeration by the diurnal variation of solar radiation.The performance tests show that the refrigeration temperature,as low as-2.9℃,with the average temperature reaching-1.5℃,can effectively protect the permafrost.