An experimental investigation is performed of the breakdown of a liquid film flowing down a vertical plate with a heater sized 150 ×150 mm. The main parameters which are varied in the experiment are the Reynolds number Re = 0.47 to 331 and the heat flux q = 0 to 1.92 W/cm{sup}2. It is found that the effect of the heat flux on the wave motion of the liquid film causes the formation of a jet flow. Dry spots are formed in the region of thin film between the jets. For the purpose of investigating the effect of wave formation on the film breakdown, the distance between the nozzle and heater is varied from 41.5 to 200 mm. It is found that the distance between the nozzle and heater defines the hydrodynamics of the liquid at relatively low heat fluxes, but has no appreciable effect on the heat flux at which the film breakdown occurs. Different working liquids and coatings of the working surface are used in the experiments to investigate the effect of the wetting angle on the film breakdown. The equilibrium wetting angle is measured by the "bubble" method. No effect of the equilibrium wetting angle on the nonisothermal breakdown of the film was revealed.
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机译：用150×150 mm的加热器对垂直板上向下流动的液膜的破裂进行了实验研究。实验中变化的主要参数是雷诺数Re = 0.47至331和热通量q = 0至1.92 W / cm {sup} 2。发现热通量对液膜的波动的影响引起射流的形成。在喷嘴之间的薄膜区域中形成干斑。为了研究波形形成对薄膜击穿的影响，喷嘴和加热器之间的距离从41.5到200 mm不等。发现喷嘴和加热器之间的距离限定了在相对低的热通量下液体的流体力学，但是对发生膜破裂的热通量没有明显的影响。实验中使用了不同的工作液和工作表面涂层，以研究润湿角对薄膜击穿的影响。平衡润湿角通过“气泡”法测量。没有发现平衡润湿角对膜的非等温击穿的影响。
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