采用烧结法制备沸腾换热用不锈钢纤维多孔表面换热管,并对其制备方法和沸腾换热性能进行了测试研究。结果表明:采用逐次套管、限位烧结工艺,实现了金属纤维多孔表面换热管孔隙度精准控制,并通过施加过渡层,有效增强了金属纤维和基管间的冶金结合;当过热度小于20℃时,孔隙度小于90%的金属纤维多孔表面换热管的换热性能比光管好,其中85%孔隙度换热管的传热系数最高可达2 400 W/(m^2·K),比光管的传热系数增大1倍。
Experiments were carried out to study the preparation methods and heat transfer performance of the porous surface heat transfer tube which was made of stainless steel fiber.The results show that,with the method of successive casing and limiting sintering process,the porosity of the metal fiber heat transfer tube can be controlled accurately.The metallurgical bonding force between the stainless steel fiber and the basic tube can be enhanced by applying a transition layer.When the superheat was lower than 20 ℃,the heat transfer property of the stainless steel fiber porous surface was better than that of the smooth tube,with the porosity of porous surface less than 90%.When the porosity was 85%,the heat transfer property of the heat transfer tube reached the highest(2 400 W/(m^2·K)),and this value was as twice as that of the smooth tube.