研究了光滑表面和不同粒径铜粉烧结的多孔表面上，以液氨为工质的喷雾相变冷却的传热特性。研究发现在相同工况下，由于多孔结构的毛细作用和潜在的有效汽化核心数强化了多孔表面的换热性能，多孔表面的换热性能远高于光滑表面。随着烧结铜粉粒径的减小，在核态沸腾区的换热效果增强；对于烧结粒径为28 μm和49 μm的多孔表面，在流量为0.0133 m3 /(m2·s)，热流密度为367 W/cm2时，换热系数分别高达100612 W/(m2·K)和96464 W/(m2·K)；当流量从0.0133 m3/(m2·s)提高到0.0181 m3/(m2·s)时，维持其他实验工况不变，多孔表面的核态沸腾延长，并且推迟临界热流(CHF)密度出现；在热流密度达367 W/cm2时，0.0181 m3/(m2·s)流量下的换热系数达到147503 W/(m2·K)，换热系数相对于0.0133 m3/(m2·s)时提高了约47%。

The heat transfer characteristics of the spray cooling with ammonia are experimentally investigated on a smooth surface and two porous surfaces with different sintered grain sizes. It is found that porous surfaces significantly enhance the heat transfer as a result of wicking action of porous structure and potential active nucleation sites. In nucleate boiling region, with the decrease of sintered grain size, heat transfer of porous surfaces performs better; the maximum heat transfer coefficients of 100612 W/(m2·K) and 96464 W/(m2·K) are achieved with the heat flux of 367 W/cm2 at the flow rate of 0.0133 m3 /(m2·s) for the porous surfaces with sintered grain sizes of 28 μm and 49 μm. When the flow rate increases from 0.0133 m3/(m2·s) to 0.0181 m3/(m2·s), the appearance of critical heat flux (CHF) density is delayed and the heat transfer coefficient is increased by 47% to reach 147503 W/(m2·K) at the heat flux of 367 W/cm2.