SimScale CAE Forum

Glider cfd


#1

https://drive.google.com/file/d/0B1tRj_PWgs_CVHVWNjZFc3FxUmw3UENWb0RyWkNEWWdMSUsw/view?usp=drivesdk
Could I get some help in simulation of the cfd


#2

Hey Roshan!

As discussed in LinkedIn I am tagging my (simulation) buddies. @jhorv_th, something for you :slight_smile: Also tagging @DaleKramer as well as @Retsam here.

Best,

Jousef


#3

@captainroshan: no assess to your link. Possibly you need to make it public.


#4

I checked it wasn’t on ,you should be able to access it now


#5

Hi @captainroshan. Your glider looks simple, but you would not be able mesh it correctly for SimScale CFD simulation. Look at that rear side:

‘Horizontal stabilizer’ floats, touching or near touching the fuselage. This should be mended.

Once fixed, look at SimScale > Public Projects. Search for ‘Glider’. You will find many examples which should inspire you. Also many useful projects are in Aerospace category.

You can copy an existing project and add new geometry to it (yours).

Cheers,

Retsam


#6

okay thanks but im not sure how to perform a simulation on it
Here’s the new link
https://drive.google.com/file/d/1r7_NG8LY760PBoWkWamwUYgzGLnI46hB/view?usp=drivesdk


#7

May I suggest to look at Tutorials, if you wish to learn how to do a simulation, please?

Tutorial on External CFD

Cheers,

Retsam


#8

thanks a bunch retsam


#9

Hey @captainroshan,

I think the first step would be indeed to fix your model. Do you have the experience to do that? If not, I can readily help you! :slight_smile:

Regards,
János


#10

yes i’d be more than happy to recieve some help
https://drive.google.com/drive/folders/1tDKujb0qAKjKfcZkSmBZYGYxhK5BCwLV?usp=sharing


#11

Well, I’ve opened your step file and it looks pretty good now! :slight_smile:
Next step is the simulation:

You can copy this project which is quite close to yours:
https://www.simscale.com/projects/jhorv_th/glyder/

Simply swap the model, adjust the boundary box size, generate the mesh and run the simulation according to your parameters. That’s it. :slight_smile:

Just let us know when you get stuck!

Jani


#12

attached in the link are some of my simulation pics
https://drive.google.com/drive/folders/1tDKujb0qAKjKfcZkSmBZYGYxhK5BCwLV?usp=sharing
i copied your project , il share mine could you have a look at what ive done and tell me if theres something wrong
https://www.simscale.com/projects/captainroshan/glider_1/
@jhorv_th


#13

Cool, you managed to do a successful simulation rather quickly! :slight_smile:

There are some points which should be improved in order to get better results:

1. Boundary/Cartesian box:
The box you specified is too small. Please use these values as a good starting point:


Of course -since you make a simulation around an airplane- make 1-2L Below the belly of the fuselage.
It’s always good to make use of symmetry constrain too. Halves mesh generation and simulation time.

Check this article, it’s really useful!

2. Boundary conditions

Velocity inlet
Are you sure that 60m/s is the cruising speed of this RC solar plane? It’s 216 km/h, pretty fast. 60km/h is 16.7 m/s. :slight_smile:

Wall 4
The Moving wall is not necessary in your case. It could be like Wall 3 faces.

With these fixes you should get better simulation runs.

And it is also very useful to check other public projects which are similar like this. You can see what parameters, what settings are used.

Keep up! :slight_smile:


#14

Could you help me with the symmetry thingy I’m unsure how to use it


#15

@captainroshan: You possibly did not notice that fragment of drawing above. I make a zoom:

image

The geometry (in that case so called ‘Ahmed body’) has 1/2 of it within BMB.

That plane (face) of BMB which splits geometry will become a ‘symmetry’ BC (Boundary Condition). Please do the same with your geometry.

That way you can halve the meshing / simulation time.


#16

Exactly! Feel free to study and copy the project I linked before. Symmetry constrain is pretty straightforward:

Good luck! :slight_smile:
Jani