The maximum negative pressure at the outlet on the circulating water side of the heat exchanger is approximately 0.05 MPa
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When the outlet pressure on the circulating water side of the heat exchanger reaches -0.05 MPa, will the circulating water completely vaporize and reach its saturated vapor pressure? If the height of the heat exchanger increases further, will the outlet pressure gauge still show a maximum value of 0.05 MPa? Is that correct? Please give some advice!
This post was last edited by ylb913 on 2016-12-4 at 08:58. The outlet pressure on the circulating water side of the heat exchanger is -0.05 MPa; it is therefore impossible for the circulating water to completely vaporize. The saturated steam pressure of water at around 40 degrees Celsius is 0.0075 MPa (absolute pressure), and in terms of gauge pressure, this is 0.0075 – 0.1 = -0.0925 MPa. The pressure of -0.05 MPa is higher than the saturated steam pressure of water. If the height of the heat exchanger is increased further, the pressure indicated by the outlet pressure gauge will drop even more, until it reaches its saturated vapor pressure. Yet even at that point, the circulating water cannot be completely vaporized – how much heat would be required to achieve complete vaporization? Who will provide this heat?