Relationship between gas pipeline flow rate and pressure drop
Thread Content
If the flow rate remains unchanged and the pipe diameter is changed, with the diameter becoming smaller, the flow velocity will increase. So what happens to the pressure drop in the pipeline, and why?
The pressure drop increases because the resistance of the pipeline has increased.
Flow rate has no relation to pressure; velocity is related to pressure. If the system energy remains constant, a higher flow rate results in greater kinetic energy and lower pressure. Conversely, low speed results in high pressure.
This post was last edited by WenLumen on 2011-4-4 12:58. That’s great; please, dear teachers, help out. 5 liters of compressed air at a pressure of 5 MPa needs to be released within 5 seconds. What size of holes are required, and what type of steel pipe should be used? (The length of the steel pipe is 70 cm, with an inner diameter of around 20 mm.) Additionally, 6 holes need to be made at the lower end of the pipe to allow the high-pressure air to escape. I’ve already set up the electrical circuit; I’m not sure what size of holes should be used at the lower end (I estimate it to be 4–6 mm). It’s also important to ensure that the air emitted has sufficient force and flow rate – what should the pressure be approximately?
According to the principles of fluid dynamics, pressure drop = drag coefficient × velocity² / (2g). Actually, the flow rate of this air can be calculated: Air flow rate = 3.14 × diameter² / 4 × flow rate. I’m not sure whether allowing high-pressure air at 5 MPa to flow directly into the atmosphere will cause any problems Because I didn’t learn aerodynamics well in college.