Does the heat exchanger outlet temperature control the amount at the heat source outlet or at the inlet?
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Does the heat exchanger outlet temperature control the amount at the heat source outlet or at the inlet?
Normally, it should be the amount at the heat source inlet
They are all used to control the flow rate of the inlet steam.
It can control both the cold source and the heat source; if the heat source inlet is a gas, it controls the amount of gas, and it can also control the flow rate at the cold source inlet
In the case of a reboiler, there is also control to perform a lower-value selection control based on the liquid level in the condensate tank at the outlet of the heat circuit and the flow rate at the inlet of the heat circuit
The outlet temperature of the heat exchanger is generally controlled through hot and cold bypasses; when the temperature rises, the outlet valve closes automatically, and accordingly, the opening degree of the bypass valve – namely the valve between 100 and the outlet – increases. In my view, it is the change in temperature that controls the amount of flow at the outlet, which in turn affects the flow through the bypass. The total flow before and after the heat exchanger remains unchanged
I don’t understand; even if there is a phase change, how can the amounts at the outlet and inlet of a heat exchanger that doesn’t have cross-flow still be different? It’s probably the difference between installing the control valve before the inlet or after the outlet. Generally, the heat source is in the gas or liquid phase, with the control valve installed before the inlet of the heat exchanger ； When the fluid is in the liquid phase and a phase change may occur, to prevent gas blockage, control valves are generally installed after the heat exchanger outlet.