Questions regarding discharging the heating extraction steam condensate at 50°C and 0.4 MPa into a condenser (vacuum vessel) with a back pressure of 4.9 KPa?
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The heating extraction steam from the turbine, at 50°C and 0.4 MPa, is discharged into the condenser (vacuum vessel) with a back pressure of 4.9 KPa. If it were discharged into the gas phase space, flash vaporization would occur; so what happens when it is discharged below the level of the hot well? Please, experts, give me some advice!
Do you mean to pump 0.4 Mpa into the hot water well? At atmospheric pressure in hot water wells, flashing occurs as well: part of the water vaporizes while the rest remains as 50-degree hot water.
Vaporization will also occur, but the amount of vaporization will be smaller.
This post was last edited by 375189182 on 2016-4-10 17:33. What are the differences between flashing on the water side and the gas side? Is it because the static pressure of water was taken into account? Is it equivalent to a pressure slightly higher when discharged into water compared to when discharged into the gas phase?
A hot well is a vacuum vessel at 4.9 KPa (absolute); will it flash even when underwater?
Flash evaporation occurs whenever the pressure is below the current saturated vapor pressure
There will also be a lot of flashing, but the amount should be much less； At 4.9 kPa, the temperature of the hot well water should be below 28 degrees, and its volume is quite large; when mixed with your water at 50 degrees, the temperature will rise a bit and some flashing will occur.
Isn’t the saturation temperature corresponding to a flash vapor pressure of 4.9 KPa? So it goes from 50 degrees to around 32 degrees for saturated water and saturated steam?
Isn’t there still a supercooling of 4.2 degrees? So it’s lower than 32 degrees.