在吸附制冷系统中，常用的吸附剂为粉末或颗粒形态，吸附剂颗粒之间的热阻和吸附剂与传热面之间的接触热阻很大，而采用固化吸附剂可以有效提高吸附剂的导热性能。本文以硫化膨胀石墨（ ENG⁃TSA）为基质制备了固化活性炭（ AC）吸附剂和固化氯化钙（ CaCl2）吸附剂，针对固化吸附剂设计了无翅片的吸附床结构，并建立了一个低压蒸气驱动的吸附式制冷系统。通过实验对固化吸附剂的性能进行了测试，分析了吸附剂的传热性能、循环时间和蒸发／冷凝温度对吸附制冷系统性能的影响。结果表明：采用AC／ENG⁃TSA吸附剂，系统COP、SCP和体积制冷密度分别达到0.140，86.1 W／kg 和16.11 kW／m3；采用CaCl2／ENG⁃TSA吸附剂，系统COP、SCP和体积制冷密度分别达到0.279，288.6 W／kg 和54.03 kW／m3，性能较传统的吸附剂有明显的提高。%In adsorption refrigeration systems, adsorbent commonly used is in the form of powder or granular. The thermal contact resist⁃ance between adsorbent particles and the thermal contact resistance between the sorbent and heat transfer surface are large. Using consoli⁃dated adsorbent is an effective way to improve heat transfer performance. In this paper, expanded natural graphite treated with sulfuric acid ( ENG⁃TSA) is employed as the host matrix of composite activated carbon ( AC) and composite CaCl2 adsorbents. An adsorption pro⁃totype using separate thermosyphon heat pipe technology is established. Owing to the highly thermal conductive consolidated adsorbents, no fins are needed inside the adsorbers. In the experiments, the system performance is analyzed from three aspects:heat transfer perform⁃ance, cycle time and evaporation/condensation temperature. The results show that the COP, SCP and volumetric refrigeration density of the system employing AC/ENG⁃TSA are 0. 140, 86. 1W/kg and 16. 11 kW/m3 , respectively, the COP, SCP and volumetric refrigeration density of the system employing CaCl2/ENG⁃TSA are 0. 279,288. 6 W/kg and 54. 03 kW/m3 , respectively. The refrigeration perform⁃ances are improved significantly compared with conventional adsorbents.
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