What is the appropriate flow rate of liquid nitrogen in the pipeline?
Thread Content
What should be the appropriate flow rate of liquid nitrogen in a vacuum-insulated pipeline? I see it mentioned that the flow rate of LNG should be less than 1 m/S before the pump, and less than 3 m/S after the pump. Could some expert tell me if there is a standard for this?
There are generally no mandatory standards for flow rate; the main consideration is that a low flow rate at the pump inlet helps to prevent cavitation in the pump. Excessive outlet flow velocity causes pipeline vibration and high pressure drop.
The flow rate also needs to take into account the properties of the material itself.
The inlet flow velocity of the liquid nitrogen pump shouldn’t be too high, right?
Vacuum: 0.05～0.3 m/s, p≤0.6 MPa (gauge pressure); 0.3～0.8 m/s, p≤2.0 MPa (gauge pressure); 0.8～1.5 m/s
Yes, the flow rate you provided is reasonable.
Generally, it should not be greater than 1 in front of the pump, and not greater than 3 behind it. However, this also depends on the physical properties of the material. I just learned this!
Yes, especially with liquid nitrogen; too high a flow rate makes cavitation more likely to occur