Huge thanks, Vin. I'm not sure if you created part 2 due to my enquiry, but I am so thankful that you did it in just 3 weeks after. That's exactly what I need for my project now. Best wishes, Maciej
thank u so much sir... i have one question...whats d exit pr. u have taken??... and cn i get access to ur matlab code for MOC??... it would b very helpfull...
Good day sir. May I ask about the method you used in the setup where you used air as the fluid, is it applicable to all fluids? If not, may I ask if how can I add fluids ( in my case, potassium nitrate and dextrose)?
Thank you so much for posting! I had been having trouble modeling strong shocks for an asymmetric wind tunnel in Ansys and this video helped immensely.
I don't get the same options in my mesh settings as you show at 3:28. Namely I don't have any drop down menus that have sizing options like course and fine. In my sizing drop down menu from top to bottom I have: Field name (input) Use Adaptive Meshing (yes/no) Growth Rate (real number) Capture Curvature (yes/no) Capture Proximity (yes/no) Enable Washers (yes/no) and then the remaining three lines are just generated stats about the mesh (and in case you are wondering, I am not looking in the quality or statistics menus, I am definitely in the sizing menu). Your videos have really helped me in the past, and I'm sure that last time tried doing this tutorial I didn't have this issue, but now I'm stumped.
This is very interesting. I was hoping to do a Rocket Nozzle CFD simulation for my project, although I am not sure if I should get my geometry from the published literature and compare the experimental and computational results, or if I should create my own geometry through the method of characteristics. I am also encouraged to do an optimization but I am not sure what technique to use. Great video!
@@VijetaTantry So I designed a rocket engine somewhat recently for my college degree from scratch for a sponsored study, and I can help point you in the right direction. I advise not messing with method of characteristics unless the engine is going to be actually built or proposed for something. If this is just for learning, use a parabolic approximation of the nozzle and use an 80% cone length. Expansion ratios can be calculated using the throat/exit area equation from Rocket Propulsion Elements by Sutton on page 59, the data on the atmosphere you are designing your engine to run in (Sutton page 747), the performance data of your propellant (Sutton page 180), and the nozzle configuration diagrams on Sutton page 77. That should give you a good start for designing your own nozzle while also letting you know the characteristics of your exhaust gases. Throwing your combustion chamber data into RPA (the free version) will help you get the stuff like exit velocity and mach number without forcing you to go into advanced fluid calculations by hand before you can plug the nozzle into CFD. I hope this helps, and good luck!
Using the formula of the Throat Temperature with your values of k, R and Tc the result is 2982000 K, is a lot of temperature so the formula is wrong, the right formula is 2Tc/k+1 and you can find it in the book Rocket Propulsion Elements - G.P. Sutton, page 57 ecuation 3-22. Using the Exit Velocity formula I can't obtain good values so I think that the formula is wrong too, I recommend to use the formula of Rocket Propulsion Elements book, page 52, ecuation 3-16. Thanks for your work.
In CFD post there is no option to select Mach Number as a variable even though i could create a contour in fluent as have it displayed. How do i get mach number as a variable in post?
Why was your outlet pressure higher than atmostpheric? I thought the pressure would go down (approaching zero gage pressure) as altitude increases? When would you run or test a rocket at higher than 1 atm back pressure?
Hello. I getting the "Unable to update geometry" error. How may I fix this? I am definitely uploading a .SLDPRT file, but it doesn't want to update. I am importing from a GrabCAD folder that is saved locally onto my computer. Any advice? Thanks
Cant we use Non reacting multi species model to do the simulation by using mixture template and defining the hot gas and air fluid separately as a mixture tempelate..... I am trying using mixture tempelate but getting some error
Sir, I followed the same steps you have explained. But when it comes to the results, I cannot see any contours colour distributions nor the surface inside the geometry.. Please advise me wat to be done?
I am student and l worked on bell nozzle but it doesn't converge when I use density based l tried to refine my mesh but it doesn't work however it converges with pressure based My question why doesn't it work with density based ? And can I use pressure based for supper sonic application? I need answers please help me
I tried to do the same, but i get " tempeature limited to 1.000 in node2. Excess temprature change in 112 cell" type message and then the solution diverges
Hi VDEnginnering! Your video is helpfull. Maybe you can advice me to my simulation. I have a CD nozzle (de Laval), with 10 bar at the inlet and 10e-5 bar at the outlet, whch is 20 mm far away from the nozzle exit. I want to see density 200 microns from the nozzle exit. But it doesn't converge. I tried FMG, pseudo-steady, inviscid (properly its viskous k-w SST is recomended). What can i do?
Sir,why can't I import a CATIA model(wireframe) in Ansys...it's showing error...and mainly how did you open the fluent-design...I can't open it..it's opening fluent-Meshing sir
Hi how do you design the chamber size looked for a few papers on effective design of the chamber domain nothing too related came up any help would be appreciated thanks
Actually iam trying to analyse under,over, optimum nozzle in ansys Fluent But the boundary conditions are causing trouble. Iam confused . Please can you help me with the boundary conditions . Just give example and I'll understand please 🙏
Thanks this video I'm finding it really helpful. I'm running into an issue as I'm doing face split for all the lines at the inlet, throat, outlet and farfield. What happens is that the last face split won't work and shows a red error sign. Is there any way to get around that? Thanks!!
I would post an image to show you what i'm talking about but TH-cam will only allow me to write in text. Is it possibly to message you the pictures somehow?
Hey i keep getting an error saying "floating point exception" whenever i try to run the calculations, everything else up to that point is working fine and i've set my settings identicle to yours
@@rodmonteon1562 I have the same problem. I tried your way, but it didn't work. So I just changed to the Pressure-based solver, and nothing else changed. Finally, the Mach number image is almost the same as in the video, but the boundary is more expansive even beyond the computational domain. I guess the reason is that the size of the nozzle outlet is not exactly the same as that in the video. I am a beginner. Could you please give some explanation about this? Thanks very much!
@@yinjiaoking8195 yes i think i can help, if your simulation converges, but the shockwaves extends beyond the domain, the only thing you need to do, is increase the farfield domain. My domain was 50 mm tall by 500 mm long, but it was too short, just increase the area of your 2D surface.
you're great. i wonder how did you design your nozzle contraction section the section that flows goes in and mach number becomes 1. i am looking forward to have your advises for my design problem. thxx
Sir,why can't I import a CATIA model(wireframe) in Ansys...it's showing error...and mainly how did you open the fluent-design...I can't open it..it's opening fluent-Meshing sir
I had done a similar simulation for a mini project, but my professor outwardly rejected it, saying that its not acceptable, as it was a steady simulation. Can anyone explain, do the results matter much in steady and unsteady analysis.
@@aerojetrocketdyners-2538 Hi I am still don't get the point what type of turbulent that I have to choose, I saw many video in youtube but someone use K omega SST, Kepsilon Realizable,Kepsilone RNG,LES,SPlarat Almaras and so on I don't know what case I have to choose it ,please help me,thank you so much
Hi! thank you for this video,.... please, can you explain me how did you design the throat of the nozzle ? and can u send me ur code MATLAB methode for reference...wud b very helpful...thank you
@@VDEngineering Could you be able to explain how to set for a nozzle with a thickness please because I can not import my coordinates. It's 2D however it has a wall thickness, and i guess the meshing setup is different?
Part 2 is uploaded! It shows you how to find thrust and verify your results
th-cam.com/video/qPYso99wMyw/w-d-xo.html
Huge thanks, Vin. I'm not sure if you created part 2 due to my enquiry, but I am so thankful that you did it in just 3 weeks after. That's exactly what I need for my project now.
Best wishes,
Maciej
thank u so much sir...
i have one question...whats d exit pr. u have taken??...
and cn i get access to ur matlab code for MOC??...
it would b very helpfull...
Why we required farfield geometry shape?
Good day sir. May I ask about the method you used in the setup where you used air as the fluid, is it applicable to all fluids? If not, may I ask if how can I add fluids ( in my case, potassium nitrate and dextrose)?
QA - why does the nozzle has to be round ?
Video is just great, straight to the point no extra line, worth spending time
Thank you sir
Thank you so much for posting! I had been having trouble modeling strong shocks for an asymmetric wind tunnel in Ansys and this video helped immensely.
Dear Sir, Can you please add the 2D geometry creation step and detailed meshing step slowly.
Can you please explain how to make the 2-D geometry in solid works?
I don't get the same options in my mesh settings as you show at 3:28. Namely I don't have any drop down menus that have sizing options like course and fine. In my sizing drop down menu from top to bottom I have:
Field name (input)
Use Adaptive Meshing (yes/no)
Growth Rate (real number)
Capture Curvature (yes/no)
Capture Proximity (yes/no)
Enable Washers (yes/no)
and then the remaining three lines are just generated stats about the mesh (and in case you are wondering, I am not looking in the quality or statistics menus, I am definitely in the sizing menu). Your videos have really helped me in the past, and I'm sure that last time tried doing this tutorial I didn't have this issue, but now I'm stumped.
Scratch that, it didn't really affect the meshing, after I applied all the manual edge sizing features
This was my first Ansys fluent simulation. Very cool🎃
This is very interesting. I was hoping to do a Rocket Nozzle CFD simulation for my project, although I am not sure if I should get my geometry from the published literature and compare the experimental and computational results, or if I should create my own geometry through the method of characteristics. I am also encouraged to do an optimization but I am not sure what technique to use. Great video!
I'm kinda in the same phase now.
what did you end up doing?
@@VijetaTantry So I designed a rocket engine somewhat recently for my college degree from scratch for a sponsored study, and I can help point you in the right direction. I advise not messing with method of characteristics unless the engine is going to be actually built or proposed for something. If this is just for learning, use a parabolic approximation of the nozzle and use an 80% cone length. Expansion ratios can be calculated using the throat/exit area equation from Rocket Propulsion Elements by Sutton on page 59, the data on the atmosphere you are designing your engine to run in (Sutton page 747), the performance data of your propellant (Sutton page 180), and the nozzle configuration diagrams on Sutton page 77. That should give you a good start for designing your own nozzle while also letting you know the characteristics of your exhaust gases. Throwing your combustion chamber data into RPA (the free version) will help you get the stuff like exit velocity and mach number without forcing you to go into advanced fluid calculations by hand before you can plug the nozzle into CFD. I hope this helps, and good luck!
@A I don't know if you are still interested, but you should check my comment to Vijeta Tantry if you want to dive in more and haven't already.
Could you please give the missing dimensions ( 0:51 ) of the nozzle?
Excellent video comprehensive and detailed.👍
e
This is next level, dude... Very nice.
Could you recommend good resources to study this method of characteristics? Thanks
You're a hero!
Using the formula of the Throat Temperature with your values of k, R and Tc the result is 2982000 K, is a lot of temperature so the formula is wrong, the right formula is 2Tc/k+1 and you can find it in the book Rocket Propulsion Elements - G.P. Sutton, page 57 ecuation 3-22. Using the Exit Velocity formula I can't obtain good values so I think that the formula is wrong too, I recommend to use the formula of Rocket Propulsion Elements book, page 52, ecuation 3-16. Thanks for your work.
I didn't understand how you put values for gauge press & supersonic gauge press in the press inlet conditions. Could you please explain that?
Learning so much of you =D
Thanks! One question, why did we change reference pressure to 0? Are we operating in vacuum conditions?
could you please explain why was ideal gas assumption taken for this case, where we're dealing with very high pressures and high temperature values
In cfd post mach no. Is not showing? Please reply.
Have the same problem
In the geometry step, did you import an extruded part or a sketch. It looks like a sketch in the video but Ansys is not allowing to import a sketch.
can you explain how to design dual bell nozzle at supersonic flow
Does it include cowl wall?
In CFD post there is no option to select Mach Number as a variable even though i could create a contour in fluent as have it displayed. How do i get mach number as a variable in post?
You have to enable it by going into Data File Quantities before you run the simulation.
Great video, VD
Can you explain to me what does the 'Supersonic/Initial Gauge Pressure' mean on the pressure inlet tab? And how did you calculate?
Nothing but the initial pressure if the flow is supersonic, it doesn’t matter too much because fluent just ignores it if not initially supersonic
why did you not change the farfield parameters to match the pressure at your operating altitude?
Спасибо за труд! Товарищ!
Very helpful!
If you were at altitude and using gauge pressure why was your outlet pressure positive? Wouldn't that imply greater than sea level pressure?
Why was your outlet pressure higher than atmostpheric? I thought the pressure would go down (approaching zero gage pressure) as altitude increases? When would you run or test a rocket at higher than 1 atm back pressure?
I don't do this stuff anymore
which software is used for CFD in videos ?
thanks for video
but can You help: how you calculate initial gauge pressure?
Hello. I getting the "Unable to update geometry" error. How may I fix this?
I am definitely uploading a .SLDPRT file, but it doesn't want to update. I am importing from a GrabCAD folder that is saved locally onto my computer. Any advice? Thanks
Hey there VDEngineering,
Good tutorial; however, I'm a bit stuck on your sketch. It seems as though there are some dimensions missing.
Please can you share its geometry?
named section of geometry we will give inlet, outlet we will give or automatically they taken ???
Hi
Can you upload a simulation related to supersonic jet acoustics (3D)
Hi Vin,
Can you please explain how to determine thrust generated in the simulation?
Best wishes,
Maciej
What is the problem to count it?
Hi I am having trouble meshing my 2D nozzle in fluent. Is it possible to contact you for advises where to start?
Cant we use Non reacting multi species model to do the simulation by using mixture template and defining the hot gas and air fluid separately as a mixture tempelate..... I am trying using mixture tempelate but getting some error
Hi, how did you get the construct the 2d nozzle from the graph of method of characteristics, what did you get from it?
you will get contour of the nozzle surface for given inlet and back pressure condtions the flow will expand isentropically
Hello Sir,
How should we change the Boundary condition with resect to different altitude for the Nozzle analysis.
Change the pressure at outside wall
Can you tell me what is the mean of temperature divergence detected
Please can you let me know what paper you have based your calculations from?
Sir, I followed the same steps you have explained. But when it comes to the results, I cannot see any contours colour distributions nor the surface inside the geometry.. Please advise me wat to be done?
Wow this is amazing! Thanks bro!
Hi, am struggling to simulate a similar problem. what are the differences between gauge total pressure & Supersonic/Initial Gauge Pressure??
They have to be similar, one is a guess value
I am not able to draw with the dimension provided please share the solid work file or the dimension
Please tell is this about reflecting shock waves?
yes
@@VDEngineering do you have video of making geometry from the start?
Or can you share the workbench files if possible..please
It would be great if you could go through this again but a little slower!
How is the 2d model created?
Hi, Very nice. What about to make a tutorial on combustion for rocket?
Can you please
Make summation for the natural convection in the phase change materials
I am student and l worked on bell nozzle but it doesn't converge when I use density based l tried to refine my mesh but it doesn't work however it converges with pressure based
My question why doesn't it work with density based ?
And can I use pressure based for supper sonic application?
I need answers please help me
Can I ask you if this simulation based on a published paper? and if so can you give me the citation?
I tried to do the same, but i get " tempeature limited to 1.000 in node2. Excess temprature change in 112 cell" type message and then the solution diverges
Hi VDEnginnering! Your video is helpfull. Maybe you can advice me to my simulation. I have a CD nozzle (de Laval), with 10 bar at the inlet and 10e-5 bar at the outlet, whch is 20 mm far away from the nozzle exit. I want to see density 200 microns from the nozzle exit. But it doesn't converge. I tried FMG, pseudo-steady, inviscid (properly its viskous k-w SST is recomended). What can i do?
Check your boundary conditions, if it diverges right away then 100% one of those are incorrect.
how did you create the 2D nozzle in solidworks?
Make your 2D sketch, then Insert > Surface > Planar, this will generate a 2D surface
VDEngineering thank you. The video is really helpful.
You're welcome, glad you liked it!
Sir,why can't I import a CATIA model(wireframe) in Ansys...it's showing error...and mainly how did you open the fluent-design...I can't open it..it's opening fluent-Meshing sir
Hi how do you design the chamber size looked for a few papers on effective design of the chamber domain nothing too related came up any help would be appreciated thanks
The chamber size is irrelevant for CFD purposes.
Actually iam trying to analyse under,over, optimum nozzle in ansys Fluent
But the boundary conditions are causing trouble.
Iam confused .
Please can you help me with the boundary conditions . Just give example and I'll understand please 🙏
Do you have another video explaining the method of characteristics?
That's going to be my next video
Cool I can not wait!
What does DR stands for in Thrust DR at the beginning of the video in Nozzle Design Parameters? Thanks
It's OR
You either input Thrust OR mass flow rate
Sir,
Make a video on nose cone using CFD analysis of rocket 🚀
Can you explain as to why R is taken as 355 and not 287?
I forgot lol this video is so old
@@VDEngineering ya understable 😂. No issues.
Will the wall contour change if I change the R value to 287 though?
tnx for this video
Thanks this video I'm finding it really helpful.
I'm running into an issue as I'm doing face split for all the lines at the inlet, throat, outlet and farfield. What happens is that the last face split won't work and shows a red error sign. Is there any way to get around that? Thanks!!
That happens because perhaps it's shape does not support structured mesh, please post an image
I would post an image to show you what i'm talking about but TH-cam will only allow me to write in text. Is it possibly to message you the pictures somehow?
Thanks for your reply.
You can post a gyazo or imgur link here
What are the nozzle dimensions
Hey i keep getting an error saying "floating point exception" whenever i try to run the calculations, everything else up to that point is working fine and i've set my settings identicle to yours
@Alfredo Guerra hi,i have a same problem.Have you solved it yet?
Can able to get sv file
amazing video. can you recomend so book to learn about rocket engines?
Check out "Rocket Propulsion Elements", by Sutton and Biblarz
can i do same thing with the nozzle (for satellite propulsion and attitude control for 1N) ? thank you
Of course, however you would have to change the gas properties if it's a mono-propellant or bi-propellant thruster.
hi, i got some problems in the setup steps, by running the calculation my Y-Velocity residual goes divergent, can you give some tips to fix this?
Pd: you video tutorial is aweome
i have the same problem, have you find a solution?
Yes, yo need to mantain a lower number of elements, the big problem is the difference in mesh size, try to create an equal mesh size in all the domain
@@rodmonteon1562 I have the same problem. I tried your way, but it didn't work. So I just changed to the Pressure-based solver, and nothing else changed. Finally, the Mach number image is almost the same as in the video, but the boundary is more expansive even beyond the computational domain. I guess the reason is that the size of the nozzle outlet is not exactly the same as that in the video. I am a beginner. Could you please give some explanation about this? Thanks very much!
@@yinjiaoking8195 yes i think i can help, if your simulation converges, but the shockwaves extends beyond the domain, the only thing you need to do, is increase the farfield domain. My domain was 50 mm tall by 500 mm long, but it was too short, just increase the area of your 2D surface.
you're great. i wonder how did you design your nozzle contraction section the section that flows goes in and mach number becomes 1. i am looking forward to have your advises for my design problem. thxx
Can u plz provide us the solid work ....file ..of ur rocket nozzle ..
How much thrust you got? Force in flow direction.
I would also like to know what the thrust is as im not sure what thrust OR means
Sir,why can't I import a CATIA model(wireframe) in Ansys...it's showing error...and mainly how did you open the fluent-design...I can't open it..it's opening fluent-Meshing sir
export as a iges file and then import in to ansys
Can I do follow same for 3d rocket nozzle
Yes for sure
Hello sir,
can you please send MOC code for nozzle?
github.com/Vinayak-D/MethodOfCharacteristicsNozzle
I had done a similar simulation for a mini project, but my professor outwardly rejected it, saying that its not acceptable, as it was a steady simulation. Can anyone explain, do the results matter much in steady and unsteady analysis.
He used a less accurate turbulence model. You should use SST K-omega.The pressures should be absolute.
@@aerojetrocketdyners-2538 Hi I am still don't get the point what type of turbulent that I have to choose,
I saw many video in youtube but someone use K omega SST, Kepsilon Realizable,Kepsilone RNG,LES,SPlarat Almaras and so on
I don't know what case I have to choose it ,please help me,thank you so much
Is the geometry available somewhere?
I created it in SolidWorks, you can use any CAD program
Hi! thank you for this video,.... please, can you explain me how did you design the throat of the nozzle ? and can u send me ur code MATLAB methode for reference...wud b very helpful...thank you
You can inbox me your email
my email is fadela.benzenine@yahoo.com and thank you
could you please forward me the same email? ponten517@gmail.com is the mail adress. Thank you. Your tutorials are awesome.
Hi VD Engineering, Can you please send me as well. vin.cohan@yahoo.com
bro can you send me the files to this address mohanaero32@gmail.com
Thank yoy
What if the fuel is not air but liquid hydrogen and liquid oxygen?
Use LES combustion, my computer cannot handle that
Hello , i need your help please
Hello, I need 1 million dollars please
Fuck you
@@yasserbicycle7734 LMAO.
You must be very wealthy to be able to afford all this very expensive software, VD Engineering.
I never told you how I obtained all the software ;)
Slow down on the explanation please, struggling to understand the steps.
You should already have a good understanding of how to use ANSYS for this video. I did my best to keep it concise and not boring.
@@VDEngineering Could you be able to explain how to set for a nozzle with a thickness please because I can not import my coordinates. It's 2D however it has a wall thickness, and i guess the meshing setup is different?
you should have done the tutorial a lot slower
You should have discovered that the pause button exists on videos.