When steam is cooled and depressurized, how does the temperature change during the depressurization process? How does the pressure change during the temperature reduction process?
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When steam is cooled and depressurized, how does the temperature change during the depressurization process? How does the pressure change during the temperature reduction process? I just can’t figure it out
There’s no need to consider these two changes: the decrease in temperature is controlled by the water level in the boiler, while the decrease in pressure is controlled by the pressure control valve. These are two completely different processes
When the temperature and pressure are reduced, the temperature will certainly drop a bit as well; and when the temperature drops, the pressure will also decrease slightly. Is there a corresponding relationship between the pressure and temperature set during this process of reducing temperature and pressure? Are temperature and pressure still independent of each other, allowing them to be set arbitrarily?
Pressure and temperature can be controlled independently; they can be set without affecting each other
Pressure and temperature can be controlled independently; they can be set without affecting each other
Two independent processes. But pressure reduction causes temperature changes, and temperature reduction causes pressure changes.
Steam pressure reduction and temperature reduction... these are two different concepts. Let’s take an example: S41 → S13. The saturated temperature of S41 is 253 degrees, while that of S13 is 189 degrees. In principle, the temperature changes after pressure reduction, but in practice the change is not significant... However, since the temperature of S13 after pressure reduction is considered to be “superheated,” water is added to lower the temperature.
By looking at the phase diagram of water or the saturated vapor pressure curve, only the points that lie on the curve represent saturated vapor; water in states corresponding to the coordinates above and below the curve also exists.
According to the relationship between steam saturation vapor pressure and temperature, controlling either the temperature or pressure will achieve the same effect of depressurization
Whether it is temperature reduction or pressure reduction, there is a certain impact between the two. In actual industrial operations, however, these changes are ignored or not noticeable, and the system is treated as separate; flow rate reduction and the addition of deoxygenated water are used to achieve the desired outcome! For theoretical knowledge, one needs to look into heat transfer, with explanations of the specialized terms