can i compute the drag coefficient in an inviscid 2d (potential flow)?. if so why is ansys saying there is no available data to display everytime i try to plot.
hi sir, can you explain that which surfaces correspond to the square you selected in the report definition? Since you gave the mesh file ready, I could not understand which surfaces you named on the mesh step ?
Hi friend; Due to the detachment of the boundary layer, the Spalart Allmaras model is a turbulence model that helps to obtain precise results in this type of phenomenon. Best Regards
@@ansys_cfd I used your mesh and run for k-w-sst and it brought out 1.3715; but, the Y+ arr the square (average) = 34; so maybe it will be better when it is smaller than 1
@@ansys_cfd hi bro! can I ask which equation did u use to cal for the Re, I used the Re= rho*v*L/ muy = 1.225 * 2.8 * 3sqrt(2) / (1.79*10^-5) = 8.13 * 10^5 I saw you wrote down 6x10^5, I didnot get this point, pls tell!
When I reached the calculate part after defining the number of iterations I encountered an error which ia as follows: Error: %cx-set-label: wta[1] (widget) Error Object: #f And no calculations were made. Would you please help me resolve this issue.
Sir, I want to simulate a CL-angle of attack curve of a square pillar . By changing the velocity direction of inlet I can change the angle of attack. But I don't know how to change the reference values. Could you please tell me how can I change them?
Hi friend; Ansys Say: At the end of each solver iteration, the residual sum for each of the conserved variables is computed and stored, thereby recording the convergence history. This history is also saved in the data file. The residual sum is defined below. On a computer with infinite precision, these residuals will go to zero as the solution converges. On an actual computer, the residuals decay to some small value (“round-off”) and then stop changing (“level out”). For single-precision computations (the default for workstations and most computers), residuals can drop as many as six orders of magnitude before hitting round-off. Double-precision residuals can drop up to twelve orders of magnitude.
Great video Ninja-san. I want to ask something about Reference Values, can you explain a little bit more about the concept "Compute from" and "Reference zone". I have read the Fluent User Guide but it did not clearly mention or maybe I do not understand. Anybody who read this also please let me know. Thank you!
thanks. after using this method finally got approximate value for 3d simulation. before this i got around thousands & quite shocked 😅
Great friend.
Best regards
That was wonderful. Thanks for the tutorial.
Thanks friend. Best regards
your music is so calm.
wonderful that precisely what i was looking for.THANK YOU
You're welcome friend.
Best regards
Very good video !
Thank you
thank you very much from my heart
You're welcome friend. Best Regards
can i compute the drag coefficient in an inviscid 2d (potential flow)?. if so why is ansys saying there is no available data to display everytime i try to plot.
hi sir, can you explain that which surfaces correspond to the square you selected in the report definition? Since you gave the mesh file ready, I could not understand which surfaces you named on the mesh step ?
simple and effective! but why you don't use another turbulent model ?
Hi friend;
Due to the detachment of the boundary layer, the Spalart Allmaras model is a turbulence model that helps to obtain precise results in this type of phenomenon.
Best Regards
@@ansys_cfd I used your mesh and run for k-w-sst and it brought out 1.3715; but, the Y+ arr the square (average) = 34; so maybe it will be better when it is smaller than 1
@@FILYPTC Hi friend;
Yes for SST you need to create another mesh. Regards
@@ansys_cfd hi bro! can I ask which equation did u use to cal for the Re,
I used the Re= rho*v*L/ muy = 1.225 * 2.8 * 3sqrt(2) / (1.79*10^-5) = 8.13 * 10^5
I saw you wrote down 6x10^5, I didnot get this point, pls tell!
@@FILYPTC Yes, it is a mistake here
Can you please tell me the experimental drag calculation for a cylinder?
Could you share the mesh file?
thank u that was very helpfull, wish succesfull
Thanks friend
Best regards
How to change shape of ansys fluent,sir?
how to deal with reference values if the object is cylindrical? Is depth equal to diameter or radius?
I do analysis for airfoil. It give negative drag. What does it means? I think the mesh is good enough. Not sure where is the error
How can I export the drag coefficient chart to excel or something else?
do you work on porous flow
When I reached the calculate part after defining the number of iterations I encountered an error which ia as follows:
Error: %cx-set-label: wta[1] (widget)
Error Object: #f
And no calculations were made.
Would you please help me resolve this issue.
Thank you. what about ref values for 3D.? if a cylinder with diameter 0.5 and depth 2.5
is area 1.25 and length 0.5 ?
Where to find cd after simulation
Can calculate drag force for boat in same way?
Hello there,your videos are amazing .Please do a 3D drag lift calculation for a cube or cylinder.
Hi friend;
Here a video about a cube: th-cam.com/video/RQip8bElJEc/w-d-xo.html
Best regards
Sir, I want to simulate a CL-angle of attack curve of a square pillar . By changing the velocity direction of inlet I can change the angle of attack. But I don't know how to change the reference values. Could you please tell me how can I change them?
you saved me thx
Hi! In this case, what is the Reinold's number?
Hi friend,
I don't remember very well, but I think that is 5.98x10^5, however, if you can see the video that data appear.
Regards
Do you have a tutorial on how to make the geometry for these external flow problems using SpaceClaim?
thanks
Hello is the reference value of Density for the fluid (air) or is it for the object?
Cool video, thanks. What cd do you get with the k-w turbulence model for comparison?
Thanks friend, I don't know, I used Spalart Allmaras only.
Regards
Good job! Drag coefs. at 5:26 - which book is that?
Hi friend;
Thanks, The book is Fluid-Dynamics Drag, theoretical, experimental and statistical information by S. F. HOERNER.
Regards
@@ansys_cfd Thank you so much!
@@sergeianpilov5222 You´re welcome friend.
Best regards
@4:45 why you change this value ? i wonder.
Hi friend;
Ansys Say: At the end of each solver iteration, the residual sum for each of the conserved variables is computed and stored, thereby recording the convergence history. This history is also saved in the data file. The residual sum is defined below.
On a computer with infinite precision, these residuals will go to zero as the solution converges. On an actual computer, the residuals decay to some small value (“round-off”) and then stop changing (“level out”). For single-precision computations (the default for workstations and most computers), residuals can drop as many as six orders of magnitude before hitting round-off. Double-precision residuals can drop up to twelve orders of magnitude.
Hi
I want calculate drag force
Is it the same way?
Yeah, only difference is when you set up the report definition (see: 4:04) there is an option to switch from coefficient to drag force.
Slt monsieur svp aide moi pour l'animation de problème de fluide enfermé entre deux cylindre mobile 3D
3D
Sir, what mesh u use in this case? Sorry before, cuz im a rookie
Hi friend;
You can download the mesh from: cfd.ninja/ansys-fluent-drag-coefficient-tutorial/
Regards
Why the depth of 3 m?
Can I do the same with my 3d car ?
Yes you can it
why does my Cd change with velocity
Yes, it is correct that the Cd changes as the Reynolds number varies. I recommend reading the book Fluid-Dynamic Drag by Hoerner.
Regards
CFD ninja very good very nice 👍 👰👰
Great video Ninja-san. I want to ask something about Reference Values, can you explain a little bit more about the concept "Compute from" and "Reference zone". I have read the Fluent User Guide but it did not clearly mention or maybe I do not understand. Anybody who read this also please let me know. Thank you!
Hi friend sorry for delay, reference values is used when you need to calculate drag and lift coefficient only
@@ansys_cfdHello, for an airfoil, what Area should be added in reference values? Or for any other object. Is it always depth times height?
Wish I saw this a month ago! 4:10
Subscribe friend!
Best regards