The internal pressure of a PVC tube can be approximated using the Darcy-Weisbach equation, given specific parameters such as tube length (0.3 m), inner diameter (1 mm), and flow rate (8 mL/min). The pressure at the inlet is approximately 0.2 PSI (1450 Pa) higher than the outlet pressure, with a linear pressure change along the tube's length. Accurate calculations require assumptions about temperature, surface roughness, and water properties, but the conservation of mass principle ensures that flow rates into and out of the tube are equal.
PREREQUISITESEngineers, fluid dynamics researchers, and anyone involved in the design or analysis of fluid transport systems, particularly those working with PVC tubing and water flow.
You said you don't know the flow rate and then that you do. Which is it? More to the point: do you have a complete picture of the system configuration? If not, exactly what do you know and not know?PaulB said:I have pump of unknown flowrate pumping water through a tube of length L and diameter D. I know that the flowrate of water exiting the tube is X mL/min.
Not with the information provided, no. It could even be zero.PaulB said:I would like to know the internal pressure of the tubing, how can I calculate it? This all occurs at sea level elevation.
I know the flowrate of the water exiting the tubing. I don't have any knowledge of the florwrate of the water entering the tube. All I know is tube length, diameter, water density and atmospheric conditions. Is it possible to determine internal pressure from this?russ_watters said:You said you don't know the flow rate and then that you do. Which is it? More to the point: do you have a complete picture of the system configuration? If not, exactly what do you know and not know?
The flow rates into and out of the tube must be the same due to conservation of mass.PaulB said:I know the flowrate of the water exiting the tubing. I don't have any knowledge of the florwrate of the water entering the tube.
You said this all occurs at sea level - so it's completely horizontal? Do you know the hose material?PaulB said:All I know is tube length, diameter, water density and atmospheric conditions. Is it possible to determine internal pressure from this?
russ_watters said:The flow rates into and out of the tube must be the same due to conservation of mass.
You said this all occurs at sea level - so it's completely horizontal? Do you know the hose material?
I agree with @Dullard that with a few assumptions you can calculate an answer but if it is accurate enough for your needs is another matter.
Dullard said:what are your Length and Flowrate?
Dullard said:what are your Length and Flowrate?
Length is 0.3 m, flowrate is 8 mL/minute. How can I calculate the answer?Dullard said:what are your Length and Flowrate?