Hi, I love this video, and it was really easy to understand and follow the steps, However I do have an issue with the pressure values obtained, and I would like you to explain how I can fix it if possible. I want to have a Reynold's number of 250, I obtained this using a velocity of 2.5m/s, and with density=1 kg/m^3, Diameter=0.2m,viscosity= 0.002 Pa.s and the length of tube is 8m. Theoretically when I calculated the pressure difference between inlet and outlet (assuming P=0 at the outlet), I get a value of 32.0 Pa, However the simulation gave a value of 3.38718 Pa. So you can see that there is a major difference in the values, I was wondering if there is a specific setting or if there was an issue with entering the needed variables.
You're welcome! The facet average value of static pressure is not the same as the area-weighted average. The facet average is a simple arithmetic mean of the pressure values over the selected faces, while the area-weighted average takes into account the size of each face, giving more weight to larger areas. For most engineering applications, the area-weighted average provides a more accurate representation, especially when dealing with varying face sizes
Surface integrals are a common technical outcome in all CFD solvers. This video is created using the most recent version of ANSYS, specifically version 2023.
Great question... In our simulation, average pressures were reported at both the inlet and outlet boundaries. At the inlet, the pressure was recorded as 7.74 units, and at the outlet, it was reported as 0 units. Since Fluent does not inherently understand the specific context of our simulation (such as simulating pipe flow) or the intended purpose of the analysis, it calculates the net value as the average of these two reported pressures.
In situations where the velocity remains constant (as in a steady, uniform flow in a pipe with no changes in diameter or elevation), the dynamic pressure component (1/2 ρv^2) may not contribute to the overall pressure drop, and only static pressure changes need to be considered. The dynamic pressure term becomes irrelevant when velocity remains constant.
Let's say you have some pressure losses due to the fittings of the pipe and height. How do you find out the pressure drop due to friction, fittings and the height separately?
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Beautiful presentation. Straight to the point. No nonsense.
Thank you for your appreciation
Sir, thank you. Very clear and easy to follow with an example that was also well structured and simple.
Glad it was helpful!
Hi, I love this video, and it was really easy to understand and follow the steps, However I do have an issue with the pressure values obtained, and I would like you to explain how I can fix it if possible.
I want to have a Reynold's number of 250, I obtained this using a velocity of 2.5m/s, and with density=1 kg/m^3, Diameter=0.2m,viscosity= 0.002 Pa.s and the length of tube is 8m.
Theoretically when I calculated the pressure difference between inlet and outlet (assuming P=0 at the outlet), I get a value of 32.0 Pa, However the simulation gave a value of 3.38718 Pa.
So you can see that there is a major difference in the values, I was wondering if there is a specific setting or if there was an issue with entering the needed variables.
Thank you for your prsentation,
is the facet average value of static pressure the same of area weighted average of static pressure or not?
You're welcome! The facet average value of static pressure is not the same as the area-weighted average. The facet average is a simple arithmetic mean of the pressure values over the selected faces, while the area-weighted average takes into account the size of each face, giving more weight to larger areas. For most engineering applications, the area-weighted average provides a more accurate representation, especially when dealing with varying face sizes
what is now instead os surface integrasl in latest ansys
Surface integrals are a common technical outcome in all CFD solvers. This video is created using the most recent version of ANSYS, specifically version 2023.
Beautiful explannation sir tysm strainght to the point
You're most welcome
tHANK YOU SIR.. pressure at inlet is 7.74, at outlet 0 net is 3.87. How this net is 3.87 I did not understand it. Please can you explain?
Great question... In our simulation, average pressures were reported at both the inlet and outlet boundaries. At the inlet, the pressure was recorded as 7.74 units, and at the outlet, it was reported as 0 units. Since Fluent does not inherently understand the specific context of our simulation (such as simulating pipe flow) or the intended purpose of the analysis, it calculates the net value as the average of these two reported pressures.
Can tell me the "methods" used
I hope all the methods and details are included in the video. Can you please elaborate on what you mean?
You are using thé static Pressure
I think it should to use the total pressure to calculateur Pressure drop
In situations where the velocity remains constant (as in a steady, uniform flow in a pipe with no changes in diameter or elevation), the dynamic pressure component (1/2 ρv^2) may not contribute to the overall pressure drop, and only static pressure changes need to be considered. The dynamic pressure term becomes irrelevant when velocity remains constant.
Let's say you have some pressure losses due to the fittings of the pipe and height. How do you find out the pressure drop due to friction, fittings and the height separately?