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对一台翅片管式熔盐-气体换热器进行了传热性能实验.实验热介质为混合硝酸盐,冷却介质为空气.利用修正的威尔逊法获得了熔盐在空气冷却边界条件下的管内流动传热准则关系式,该关系式适用于2378＜Re＜12075,10.5＜Pr＜ 11.本文对换热器传热过程中的热阻进行了对比分析,分析结果表明,管程熔盐的对流传热热阻对该换热器传热性能的影响基本可以忽略不计,翅片管的导热热阻和壳程气体的对流传热热阻是影响该换热器性能的两个重要影响因素,并且随着气体流速和换热系数的提高,翅片的导热热阻将会逐渐成为影响换热器性能的最主要因素.“,”A finned tube molten salt to gas heat exchanger is tested in this paper.A nitrate salt mixture (NaNO3-KNO3-NaNO2) is used as the hot fluid on the tube side,cooled by air on the shell side.An empirical correlation is proposed to calculate heat transfer coefficients for the molten salt in heat exchanger tubes with air cooled conditions,based on a modified Wilson plot method.The correlation is obtained within the range of Reynolds number from 2378 to 12075 and Prandtl number from 10.5 to 11.A detailed thermal resistance analysis is conducted.It is shown that resistances caused by the finned tube and air both have great impacts on the performance of the heat exchanger while resistance caused by molten salt can be neglected.In addition,the finned tube resistance will be major if the air velocity is improved.