Modelling of tubercles on aerofoil

[naveenkumar6]

Hi all,

can anyone please help me how to draw tubercles as shown in the figure on an aerofoil blade attached here

blade.zip consists the iges file of the blade for which i want to add tubercles

Thanks

Naveen

[TomD.inPDX]

Some analysis extensions have the ability to output 3D data from the resulting analysis.

I am not sure I would tackle each curve on their own to mimic this process.

[naveenkumar6]

Hi TomD,

The image which I have attached is from google, so I don't have any data regarding it.

I'm attaching few more images and hand sketches.

Thanks

Naveen

[TomD.inPDX]

Right.  I am saying you would need to do the airflow analysis to capture the data. 

I have done something similar with the lite version of the FEM analysis.

I would run the deflection analysis and output the deformed model in a facet format.

This file will maintain all the colors from the analysis as well as geometry I can query.

[TomD.inPDX]

Am I misunderstanding your request?  I was thinking you are asking about the analysis results rather than the geometry since this is what is highlighted in numbers.  If you are asking about the geometry, then your image may be misleading.

This type of surface can be accomplished with sweep using the variable sweep option.

You would use Trajpar statements or graph functions in the sweep sketch to create the undulations.

[naveenkumar6]

Hi TomD,

I was requesting for the model, not the analysis

Thanks

Naveen

[TomD.inPDX]

I get it now.  The more defined your request the more likely we can help. 

There are just so many ways things can be made in Creo.

You can even use the Warp feature for something like this.

Understanding the use case just gets us on the right track much quicker.

It is also helpful to know how much experience you have with this type of surfacing;

and which, if any, optional Creo modules you have available.

Just to be complete 🙂

[naveenkumar6]

Hi TomD,

I have learnt CREO just as a part of the curriculum from my institution, and know only a few basic tools from the creo.

Thanks

Naveen

[TomD.inPDX]

Fair enough; have a look at the attached.

[naveenkumar6]

Hi TomD,

I want to have something like that but it is irregular in the model you attached. Moreover, it is also changing the basic shape of the blade.

can we make it as a curve driven??? And without affecting the basic shape???

Thanks

Naveen

[TomD.inPDX]

Boundary Blend, Sweep, Sweep Blend, pick your poison.  Get your curves set up.  Figure out how you are going to manage tangencies, or worse, continuous surfaces.  NOT a simple undertaking.

If you have the surfaces module, you may have better options. 

Core Creo is simply lacking in quality engineering surfaces.

Of course my model was a quick push and pull.  It follows its own rules.  Even Wrap is an adventure!

[naveenkumar6]

Thank You TomD

I do have surface modelling option but I'm lack of practice to get such a surface 

[TomD.inPDX]

The reason I mention the surfacing module is that it has better ways to blend surfaces.

With core Creo, it is tedious at best to join surfaces with a high degree surface quality.

[naveenkumar6]

Hi TomD,

Could you please help me to and model it as an example

[TomD.inPDX]

I would need real design parameters to go by.

Also know that I do not have advanced surfacing capability.

[naveenkumar6]

Hi TomD,

I have already attached the model in the first post of my thread and waves can be of sine eqn and amplitude or wavelength  or no. of turns can be of any number

[TomD.inPDX]

Fair enough, now the model you provided needs a flat leading edge per the examples and other posts.

Please determine and trim your model to show where the wing stops and the tubercles begin.

It may be difficult to maintain tangencies depending on the method used.

Although I agree, this is a challenge in any such air foil.

And before I do this for you, you need to try some of the recommendations made by others.

I'd like to see how you are getting on with what you've learned from this discussion.

Forum members are here to help guide you to do what you are trying to achieve.

Often times we get inspired to flesh out a optimized solution.  This is not the norm.

Therefore, please try this challenge by providing the parameters you have stated in geometry.

Trim back that leading edge; add some sketch geometry in both directions for the profile you want.

From there we can continue to move forward.

[dschenken]

This has been discussed before: https://community.ptc.com/t5/Creo-Modeling-Questions/Create-waves-at-leading-edge-of-aerofoil/m-p/111689#M28214

[TomD.inPDX]

I thought it sounded familiar 🙂

[naveenkumar6]

Hi dschenken,

I have seen that post but it is having a vertical surface and mine is NACA aerofoil, and the blade in that post is having a single profile with extrude option but in my case I have different sections with different pitch angles, so I have even attached the iges file of the model.

Thanks 

Naveen

[dschenken]

The vertical surface is from the truncated portion of a standard airfoil. Forward of that location is being replaced with the new geometry. It takes little imagination to see that creating the entire airfoil by using more guide curves would allow you to do whatever is required.