A water film flash evaporation vacuum ice-making system is developed. The experiment was carried out to investigate the influence of flash evaporation pressure, thickness and initial temperature of water film on the flash evaporation process. The thickness of the water film was 15, 35, 55 and 75 mm. Initial temperature of water film ranged from 2℃ to 10℃ , and flash evaporation pressure varied from 100 Pa to 600 Pa. The characteristics of the flash evaporation process were recorded using a CCD camera of the visualization system. The experimental results show that under the operating conditions, lower flash evaporation pressure leads to faster change of water film temperature at constant initial temperature of water film. Higher initial temperature of water film makes the water film temperature varies more quickly at constant pressure. As water film thickness increases, the decrease rate of water film temperature reduces. Based on the experimental results, a correlation for water film temperature with flash evaporation pressure, thickness and initial temperature of water film is presented with the maximum error of 24. 19%.
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