[cfd seeker]

Ali you are a great man, Thanks alot for this. Theoretically I have fully understood the procedure but practically I do not know how to perform step no. 2 and step no.4 i.e how to insert Ogrid inside block?please explain its procedure and how to transform a block behind wing into Yblock?also explain its procedure

[diamondx]

to perform an ogrid just foloww the image below





and for the ygrid




Hope you got it !!

[cfd seeker]

Thanks alot Ali once again for your hardwork. So from your post what i get is that "for creating ogrid inside block we don't have to select any face and we don't have to check "Around" option". right? secondly this Ogrid will also be inserted in the tip block?

[diamondx]

no you don't have to select around. sorry my mistake, about faces yes , in our case you should select the face in FF and SYM. i guess you know the impact of selecting faces when creating ogrid. what do you mean by tip block, the block next to trailing edge ? you will transform it in ygrid

[cfd seeker]

NO I do-not know the impact of selecting faces while creating Ogrid and that's where I am facing problem, please explain this point and which faces exactly we will have to select in our case? by tip block I mean the block in the wing tip region not in the trailing edge region(the block adjacent to wing block in the z-direction, hope you got it?)

[diamondx]

here is a video of far explaining what happens when you create ogrid and select faces:
http://www.youtube.com/watch?feature...&v=dHfAe_6weZE
Just open a new project, create a box and apply have fun with it.
For the tip block you will do exactly like the block in the tip exactly same.

[cfd seeker]

I have watched this video before, by selecting two faces while creating Ogrid results in Half Ogrid or Cgrid...that's what i get from this and in our case three faces will be selected for creating Ogrid, one on the symmetry plane, one inside wing tip and one in the farfield parallel to the previous selected faces. right?

[diamondx]

i just selected two face, in in the farfield and sym. I don't know the effect of selecting the face in the wing tip. i guess nothing will change. but anyway yes this is how is it .

[cfd seeker]

last few things Ali.....how Ogrid will be inserted at the leading edge?its Ogrid inside or Ogrid around wing and tip blocks?in this Ogrid faces will be selected or not?? and after splitting the block near trtailing edge which you marked ny pink color, the trailing edge block will be converted to Yblock.right?? the block behind trailing edge is already merged previously.right??.

[diamondx]

how Ogrid will be inserted at the leading edge?

inside always for both tip and inside wing

in this Ogrid faces will be selected or not??

yes faces will be selected, again two faces, farfield and sym

the trailing edge block will be converted to Yblock.right??

yes.

the block behind trailing edge is already merged previously.right??

yes, you will apply ygrid to it to

[Far]

Originally Posted by diamondx

i just selected two face, in in the farfield and sym. I don't know the effect of selecting the face in the wing tip. i guess nothing will change. but anyway yes this is how is it .

Selecting the middle face is not necessary.

[Far]

Originally Posted by diamondx

yes, you will apply ygrid to it to

Not required behind trailing edge. Just a one split passing through the trailing edge vertex will do the magic. use index control, so that it does not propagate upstream.

[cfd seeker]

Far have you seen my blocking files? where I am going wrong by your method?

[cfd seeker]

helloooooooooo Far................

[venkat_aero2007]

Originally Posted by diamondx

INSIDE.look at the picture below. the initial block gave the block in red.
After that i created an ogrid inside , which is the green one. i then applied association.
after that i splitted vertically, which is purple line.
then i created another ogrid INSIDE, which is orange.
Then finally transformed the block behind in ygrid

Hi diamondx,
I have a question. I have low quality angle if I Insert Y-block at the tip of the cambered wing. Is there any way to increase the angle quality.

[venkat_aero2007]

Hi diamondx,
I have a question. I have low quality angle if I Insert Y-block at the tip of the cambered wing. Is there any way to increase the angle quality.

[Far]

Here is the method 5, which I consider is the best for wing with sharp trailing edge and rectangular domain. Min quality > 0.65 and min angle > 18

[crostolo]

I was trying to replicate method5 of Far, but I'm not able to mesh properly my geometry that has a much more sharper trailing edge than the one in the example.

I attach .tin, .project and .blk files if someone can have a look and please give me some suggestion.
Many thanks

[Far]

Either go with prism mesh or create tetra mesh in tip region.

For first option, you already have penta 6 elements, when you merged vertices at trailing edge.

For second option : Edit block > convert block type > Set type and choose the appropriate option from dropdown box.


I would be interested in second option as inner angle is too low.

PS: You can also trim trailing edge to have better mesh. Moreover practically it is not possible to manufacture such sharp angles due to limitations of tools and machines used in process.

[crostolo]

Thank you Far