Calculations regarding the temperature and pressure reduction device

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This post was last edited by williananm on 2019-8-7 at 09:33. As everyone knows, steam temperature and pressure reduction is a process of balancing the heat value. I came across the following formula by chance: Water volume for temperature reduction = Outlet steam flow rate * (Enthalpy of inlet steam – Enthalpy of outlet steam) / (Enthalpy of inlet steam – Enthalpy of water used for temperature reduction). Without taking into account the unevaporated portion, the formula becomes: Water volume for temperature reduction = Outlet steam flow rate * (Enthalpy of inlet steam – Enthalpy of outlet steam) / { (Enthalpy of inlet steam – Enthalpy of water used for temperature reduction) – 0.35 * (Enthalpy of inlet steam – Enthalpy of saturated water after temperature and pressure reduction)}. This formula can also be found in textbooks. In the formula, the amount of water used for temperature reduction is proportional to the amount of steam at the outlet. If this relationship is considered, it becomes impossible to determine the amount of steam at the outlet with accuracy; if an overly high value is assumed, the calculated amount of water used for temperature reduction loses its meaning. I would like to ask everyone: in general design, various parameters of the main steam are considered. What is the normal calculation process for determining the amount of new steam and water? Also, what degree of reference value does a rough calculation based solely on energy balance have?