How to do optimization of bulbous bow based on tip length, angle of rotation, and also width of bulbous bow of tanker ship

[Ms. Daphne Xin 0]

I am newbie Caeses software user. Please provide me some useful guidance for me. Thank you very much

Cheers,

Daphne

[Ms. Daphne Xin 0]

Secondly, please provide me some guidance about the way to do optimization hull form of ship towards reducing ship resistance using CAESES software.

 

Your help is highly appreciated to me.

Thank you

 

Best regards,

Daphne

[Ms. Daphne Xin 0]

Can anyone kindly provide me guidance or step by step to do the optimization based on bulbous bow exactly like shown in the picture?

Thank you for helps.

by Daphne :)

[Mr. Daehwan Park 1]

 Dear Daphne

 

The form variation shown in the attached thumbnails above was done from a fully parametric model. In order to get step by step idea for hull form creation in parametric way you could get information from the tutorials embeded in CAESES. Please go to Documentation Browser > Tutorials > Hull Design.

 

For bulbous bow modeling, it would be good to refer the article below. 

 

https://www.caeses.com/forum/index.php?/topic/315-bulbous-bow-shape-analysis/

 

 

Best regards
Daehwan

[Ms. Daphne Xin 0]

Hi Mr. Daehwan

 

Thanks for your help !

[Ms. Daphne Xin 0]

Hi Mr & Mrs

sorry for interrupt that i unable to export or import fdf file into caeses software,. Is there any possible step to open fdf file in caeses software ?

Thank you

[Mr. Daehwan Park 1]

Hi Daphne,

 

Could you explain your situation detailed a little bit more? 

 

Which fdf of yours and where is it saved now ?

 

 

//Daehwan  

[Ms. Daphne Xin 0]

Hi Mr. Daehwan

 

Thanks for helping me

It refer to the article share by Mr. Daehwan 

For bulbous bow modeling, it would be good to refer the article below. 

 

https://www.caeses.com/forum/index.php?/topic/315-bulbous-bow-shape-analysis/

 

For the fdf file via this article above which are bulbous bow section and also shape analysis bulbous bow

This is because my computer unable to read in fdf file.

Can you guide me the way to import fdf file in caeses software? Or make these fdf file in feature tool Caeses

 

Thank you for your help :)

 

by Daphne

[Mr. Daehwan Park 1]

Hi Daphne

 

There are several ways to import the fdf file but here I would like to introduce you the easiest one.

 

Just drag and drop.

 

Cheers,
Daehwan

 

[Ms. Daphne Xin 0]

Hi Mr & Mrs

 

Sorry to interrupt that I have one question

 

 

Does any efficient way provides to change the import geometry in FBrepPart into FNurbSurface for hydrostatic calculation, hull variation and also lackenbyshift purposes?

 

[Mr. Daehwan Park 1]

Hi Daphne

 

I guess you might have imported iges.

All segmental patches of Nurbssurface and FBrepPart should be assembled in one Brep. Then the Brep can be used in Hydrostatic proceedure and all shift variations including lackenbyShift.  

 

Cheers
Daehwan

 

[Ms. Daphne Xin 0]

Hi Mr. Daehwan

 

Thanks for your help

 

Btw, i dunno how to assembled in one Brep, can you guide me the way to do it ?

 

And the one that i show you was imported iges format file. (For example the iges file that used in tutorial "containervesel.iges'')

 

By

Daphne

[Mr. Daehwan Park 1]

Hi Daphne

 

1. Select all surface patches and brepParts.

2. During stil selected, create a new brep.

 

Then they are assembled in a one brep.

 

// Daehwan 

[Ms. Daphne Xin 0]

Hi Mr Daehwan

 

First of all, thank you for helping me in solving problem.

 

However, once i assembled in a one brep, it overlap with old brep parts and i try to delete old brep parts one by one and then whole ship model dissapear.

 

1. How to solve this problem and i just want to keep the assembled brep one only?

2. How to assembled FNurbCurve? 

 

By

Daphne

[Mr. Daehwan Park 1]

Hi Daphne

 

I guess the OVERLAP is just a matter of visual effect.

When you delete an original brepPart, then the Brep will also lose the same source.

Just click the scope having the original brepParts and surfaces to shut off. Then the color of the scope will be changed to gray and all the geometry under the scope will be unvisible.

 

 

// Daehwan

[Ms. Daphne Xin 0]

Hi Mr Daehwan

 

Again, thanks for your help 

 

For assembled different NurbSurfaces into a one NurbSurface, I applied the same assembly method like previous brep parts but still unable to assembly into a one NurbSurface. First I select all NurbSurfaces and then i create a new nurbsurface, but in new nurbsurface only one nurbsurface been selected, why does this happened?

 

Can you guide me the way to assembled different NurbSurface into a one NurbSurface for hull variation, hydrostatic calculation and also lackenbyshift purposes?

 

By

Daphne

[Mr. Daehwan Park 1]

Hi Daphne

 

NurbsSurface or BSplineSurface does not work for assembling several surfaces.

 

There is a data type SurfaceGroup that works for it. But the SurfaceGroup cannot assemble Surfaces and BrepParts together. In this CASE Brep is the alternative since Brep can assemble Surface and BrepParts in one Brep object.

 

1. Assemble the surfaces and brepParts in a Brep.

2. Create a SectionGroup with the Brep.

3. Create a Hydrostatic Calculation

4. Create a LackenbyShift using the SAC from the hydrostatics

5. Create another Brep in the same way with 1.

6. Insert LackenbyShift in the new Brep.

 

This is the proceedure that you want to make.

 

//Daehwan

[Ms. Daphne Xin 0]

Hi Mr Daehwan

 

Thanks for helping me.

 

I already assembled all surfaces in a one brep, when i doing hydrostatic calculation in creating section group , the brep i put as source but only one section been carried out.

 

The results of computation all become zero undefined.

 

The way i did hydrostatic calculation followed the tutorial.

 

Mr. can you guide me the way to solve this problem? Thank you

 

By 

Daphne.

[Mr. Daehwan Park 1]

Hi Daphne

 

I guess your model would be scaled by its length and the origin is set in the middle.

 

You need to change the position values suitable to the model.

 

 

// Daehwan

[Ms. Daphne Xin 0]

Hi Mr Daehwan 

 

Thanks for helping me

 

1. I now faced the problem which i cannot drag&drop brep object as source for image curve for new hull, hull variation and also x-end forforebody delta curve (lackenbyshift)

Is there any possible way to solve this problem, Mr. Daehwan?.

 

2. How to re-set the position value for my ship model?

Can you guide me the procedure to re-set the position values of my ship model for lackenbyshift purpose?

 

By Daphne

[Mr. Daehwan Park 1]

Hi Daphne

 

It seems that you are doing very well and soon the LackenbyShift will work successfully.

 

The ImageSurface "NewHull" can have a surface as its source.

 

In this case, please create another Brep with a certain name to distinguish it as a final hullform for example "FinalHull".

 

And in the Transformation slot in the FinalHull insert the LackenbyShift. Then you will see the shape will be transformed by LackenbyShift.

 

 

Have a nice weekend!

 

// Daehwan 

[Ms. Daphne Xin 0]

Hi Mr & Mrs professional

 

Sorry to interrupt everyone again.

 

1.   When I did free form deformation bulb, why the result of bow deformation not same as the tutorial that i practiced, i followed step by step the tutorial freefromdeformation bulbs but fail to figure out the problem.

 

I lack of knowledge about the free form deformation could you provide me some extra knowledge about deformation of bulbous bow

 

2.   Another day i able to solve this problem as shown above but for the rotate deformation fail to do variation angle of rotation of bulbous bow, why this condition happened?

 

By

Daphne