传热学v4-第七章相变对流传热

ShanghaiJiaoTong

Heat凝结传热凝结传热（气相变液相沸腾传热沸腾传热（液相变气相沸腾传热：烧开水相变传热的特点 SJTU- ShanghaiJiaoTong

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Heat 基本假设 SJTU- ShanghaiJiaoTong

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Heat7-2膜状凝结分析解及实验关联式

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Heat 沸腾换热：液 twYNNSJTU- HeatShanghaiJiaoTong沸腾传热的模 大容器饱和沸腾曲0℃∆t0℃∆t4单相自然对流区4℃∆t25核态沸腾区。产生汽泡，汽泡间的25℃<∆t<200℃:过渡沸腾区。汽泡的产生速200℃t稳定膜态沸腾区。形成稳定汽膜，虽ShanghaiJiaoTong沸腾传热的模 大容器饱和沸腾曲

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Heat 气泡产生的源泉。壁面的凹缝、裂穴最可能成为汽

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Heat7-4沸腾换热时气泡在汽化处产生，成长并逸出；之后流体补充，重新形 SJTU- ShanghaiJiaoTong

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Heat200℃t200℃t稳定模态沸腾区。形成稳定汽膜，虽然gr(

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Heat 1963 的G.M.Grover发 SJTU- ShanghaiJiaoTong

Heat LosAlamos国家 的G.M.Grover发明 热管相对于一种基于相变传热的等温导热体，较多用于表面的等温化和电子设备的温度控制。用于地面散热还需要在冷凝翅SJTU- Sha