i'm currently struggeling to model helicopter rotorblades in close proximity to the leading edge with the use of PreVABS.
By meshing the geometry with relatively thick layers of composites. The mesh will inevitably intersect at some point close to the leading edge. I've bypassed the modelling problem the "dirty" way by generating gaps. (See the attached figure). Unfortunately this of course creating more problems when soving for the stresses. I'm sure you're allready aware of this problem. Is there a better meshing approach using preVABS!?
Yes. We are aware of this problem. We are in the process of developing a better preprocessor for VABS. If you have suggestions please let us know. For your particular problem, can you artifically make each layer thinner to avoid this problem?
I just checked this problem. I can provide a example of solving the problems by GUI together with the alpha release, if you think this is a proper idea.
I just wanted to check if there is a better preprocessor or updated version of preVabs for the described problem available!? I like the idea of preVABS, because it is capable of creating crosssection meshes very quickly and a change of layup or geometry doenst mean hours of meshing.
Maybe you have also an idea of modelling a round trim weight in close proximity to the leading edge as well as considering foam or honeycomb structures.
We are currently testing our alpha-version VABS-ANSYS GUI within Dr. Yu's group now. The attached is a validated cross-section example.
Do you mind if you provide us a more realistic cross-section simulation task for our testing? A typical one which is commonly encountered during your work should be enough. And we could feedback you a most updated solution on the issues you mentioned ASAP.
I have selected a typical crosssection of a project of mine and uploaded the preVABS input files for the consideration.
You will quickly see where there is potential for further improvements close to the leading edge. The slit in the mesh is making it hard to predict torsional stiffness and shear center.
Please let me know if you have a solution for improvements.
I notice that your section has geometric overlap of material layers at the leading edge. Is that a realistic situation happening in your project and design? Or you are try to avoid this?
i was trying to avoid both the overlap and the slit between the bottom and top surface. I had a mesh in mind that uses triangles insted of quads to model the layup (Similar to the leading edge). I have attached a sketch of the modell i had in mind
Thanks a lot for your reply! I think I understand the issue now, and in fact we have another way to deal with it. I will return our solution to you soon.
Anonymous @ on — Edited @ on
Dear SwiftComp group,
i'm currently struggeling to model helicopter rotorblades in close proximity to the leading edge with the use of PreVABS.
By meshing the geometry with relatively thick layers of composites. The mesh will inevitably intersect at some point close to the leading edge. I've bypassed the modelling problem the "dirty" way by generating gaps. (See the attached figure). Unfortunately this of course creating more problems when soving for the stresses. I'm sure you're allready aware of this problem. Is there a better meshing approach using preVABS!?
Best Regards,
Tobias Pflumm
Wenbin Yu @ on
Yes. We are aware of this problem. We are in the process of developing a better preprocessor for VABS. If you have suggestions please let us know. For your particular problem, can you artifically make each layer thinner to avoid this problem?
Fang Jiang @ on — Edited @ on
Dear Dr. Yu,
I just checked this problem. I can provide a example of solving the problems by GUI together with the alpha release, if you think this is a proper idea.
Best Regards, Fang
Original Message ——-
Emailed forum response from jiang302@purdue.edu
Tobias Pflumm @ on
Dear Dr. Yu and Mr. Jiang,
I just wanted to check if there is a better preprocessor or updated version of preVabs for the described problem available!?
I like the idea of preVABS, because it is capable of creating crosssection meshes very quickly and a change of layup or geometry doenst mean hours of meshing.
Best regards from Germany
Tobi
Tobias Pflumm @ on
Maybe you have also an idea of modelling a round trim weight in close proximity to the leading edge as well as considering foam or honeycomb structures.
Best Regards,
Tobi
Fang Jiang @ on
Dear Tobias,
We are currently testing our alpha-version VABS-ANSYS GUI within Dr. Yu's group now. The attached is a validated cross-section example.
Do you mind if you provide us a more realistic cross-section simulation task for our testing? A typical one which is commonly encountered during your work should be enough. And we could feedback you a most updated solution on the issues you mentioned ASAP.
Thanks a lot for your consideration!
Best Regards,
Fang
airfoilgeometry.pdf
45 KBClick to download
Tobias Pflumm @ on — Edited @ on
Dear Fang,
I have selected a typical crosssection of a project of mine and uploaded the preVABS input files for the consideration.
You will quickly see where there is potential for further improvements close to the leading edge. The slit in the mesh is making it hard to predict torsional stiffness and shear center.
Please let me know if you have a solution for improvements.
Best Regards,
Tobi
PreVABS_input_Files_R230.zip
9 KBClick to download
Tobias Pflumm @ on
An Image of the crosssectional Mesh is attached.
Tobi
R230_VABS_Layup.pdf
39 KBClick to download
Fang Jiang @ on
Dear Tobi,
Thanks a lot for your sharing! We will redo this case using our new GUI and feedback our solution to you ASAP.
Please keep in touch!
Best Regards,
Fang
Fang Jiang @ on
Dear Tobi,
I notice that your section has geometric overlap of material layers at the leading edge. Is that a realistic situation happening in your project and design? Or you are try to avoid this?
Best Regards,
Fang
Tobias Pflumm @ on
Dear Fang,
i was trying to avoid both the overlap and the slit between the bottom and top surface. I had a mesh in mind that uses triangles insted of quads to model the layup (Similar to the leading edge). I have attached a sketch of the modell i had in mind
I hope this helps.
Best regards, Tobi
Fang Jiang @ on
Dear Tobi,
Thanks a lot for your reply! I think I understand the issue now, and in fact we have another way to deal with it. I will return our solution to you soon.
Best Regards,
Fang