Does the flow rate change if the pipe diameter is changed?
Thread Content
In our company’s circulating water system, one of the inlet pipes of the heat exchanger originally had a diameter of 159; we now want to change it to a diameter of 219. Will the flow rate of the circulating water change as a result of this change? The inlet pipe of the heat exchanger is connected to the circulating water main.
As long as the pressure of the circulating water remains constant, the flow rate through the heat exchanger is determined; changing the diameter of the inlet pipe only affects the flow rate of fluid entering the heat exchanger.
It depends on whether your total flow rate has changed; if the total flow rate remains unchanged, then the flow velocity has increased. . Common sense~~~
Flow rate Q = velocity V multiplied by area A multiplied by time T. Since pressure remains constant within the same pipeline, if the diameter changes, then the area A changes as well; with a constant flow rate, the velocity V will also change.
The change in the inlet pipe diameter only alters the flow velocity at the inlet; it does not change the flow velocity within the tube bundle inside the heat exchanger. The flow rate through the heat exchanger remains constant, as does the velocity. What changes is only the flow rate of the inlet; it does not represent the flow rate of the heat exchanger.
Ignoring the effect of changes in the inlet pipe diameter on flow rate, the flow velocity through the heat exchanger remains unaffected. What changes is only the flow rate in the inlet section.
Q=V*A; if Q remains constant, then as the pipe diameter changes, the cross-sectional area changes as well, and thus the flow rate changes.
The flow rate must change! !
5th floor is correct! The speed of the inlet pipeline slows down, but since the total flow rate remains constant, the flow velocity inside the heat exchanger also does not change
The 5th floor is the correct answer. The poster set up a trick: whether the valves for water inlet and outlet of the condenser are both fully open. If they are fully open, increasing the diameter of the inlet and outlet pipes will result in an increase in flow rate, since the circulating water pressure remains unchanged. However, if it is throttled, even if you increase the pipe diameter, the total flow rate may not necessarily increase.
The import and export valves are of course fully open