ABSTRACT This paper experimentally investigates the performance of micro and nano metfoam regenerators in alpha-type Stirling engine conditions. The thermal efficiency of this engine depends on performance of regenerator. Therefore, increase the heat recovery of regenerator raises the total efficiency. Accordingly, two types of regenerators from porous media are designed and simulated with different materials. Three-dimensional regenerator CFD simulation shows that randomize porous open cell metfoam made of silver as high conductivity and high heat capacity material is the best structure to fabricate metfoam regenerator. The porosity and matrix element diameter are optimized. The nano coating methodology enhances the activated surface. The regenerators are fabricated using casting polymer mold layer deposition. The nano silver particles are coated on the metfoam by sol-gel coating method. Experimental results show the improvement in regenerator percentage of heat recovery by 3.40% and 5.93% for micro metfoam and nano metfoam, respectively. The maximum improvement is achieved up to 8.65% in case of using the nano metfoam regenerator at 543 K.

中文翻译：

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阿尔法斯特林发动机工况下微纳米二甲基泡沫再生器的热回收性能研究

摘要 本文通过实验研究了在 α 型斯特林发动机条件下微米和纳米甲基泡沫再生器的性能。该发动机的热效率取决于蓄热器的性能。因此，增加蓄热室的热回收率可以提高总效率。因此，设计了两种类型的多孔介质再生器，并用不同的材料进行了模拟。三维蓄热器 CFD 模拟表明，由银制成的随机化多孔开孔金属泡沫作为高导电性和高热容量材料是制造金属泡沫蓄热器的最佳结构。优化孔隙率和基体元素直径。纳米涂层方法增强了活化表面。蓄热器是使用浇铸聚合物模具层沉积制造的。纳米银颗粒通过溶胶-凝胶涂覆方法涂覆在甲基泡沫上。实验结果表明，微甲基泡沫和纳米甲基泡沫的再生器热回收百分比分别提高了 3.40% 和 5.93%。如果在 543 K 下使用纳米甲基泡沫再生器，最大改进可达 8.65%。