FW-H surfaces velocity about libacoustics HOT 14 CLOSED

Same question. Do you solve this yet?

from libacoustics.

Hi, U0 is used when you move STL surface with constant velocity. However, if you use dynamic mesh and set your FWH surface as moving patch , then you get Farassat 1A formulation for non-permeable moving surface.

from libacoustics.

Hi, U0 is used when you move STL surface with constant velocity. However, if you use dynamic mesh and set your FWH surface as moving patch , then you get Farassat 1A formulation for non-permeable moving surface.

Thanks for your reply!
I have two examples with questions here:

1. The three blades are rotating with rpm 10 and radius 1 m, with inlow velocity of 1 m/s, how do I set formulationType, U0, Ufwh respectively?
2. The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?
   Best,

from libacoustics.

The three blades are rotating with rpm 10 and radius 1 m, with inlow velocity of 1 m/s, how do I set formulationType, U0, Ufwh respectively?

Set FWH control surface to patch encompassing these 3 blades, Ufwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

from libacoustics.

The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?
Best,

Set FWH control surface to the surface encompassing region in which cylinder translates and set fwh (.0 .0 .0);, nonUniformSurfaceMotion false; formulationType Farassat1AFormulation;

from libacoustics.

The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?

OR: Set FWH control surface to the surface encompassing patch of the cylinder translates and set fwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

from libacoustics.

The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?

OR: Set FWH control surface to the surface encompassing patch of the cylinder translates and set fwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

Many thanks for your attention!
According to your reply, I just need to set 'nonUniformSurfaceMotion true', and no detailed information for body motion is needed in FW-H solver parameters setting. Am I right?
Best,

from libacoustics.

The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?

OR: Set FWH control surface to the surface encompassing patch of the cylinder translates and set fwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

Many thanks for your attention!
According to your reply, I just need to set 'nonUniformSurfaceMotion true', and no detailed information for body motion is needed in FW-H solver parameters setting. Am I right?
Best,

Yes, if you select patch which encompasses the moving body as control surface

from libacoustics.

The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?

OR: Set FWH control surface to the surface encompassing patch of the cylinder translates and set fwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

Many thanks for your attention!
According to your reply, I just need to set 'nonUniformSurfaceMotion true', and no detailed information for body motion is needed in FW-H solver parameters setting. Am I right?
Best,

Yes, if you select patch which encompasses the moving body as control surface

Thanks! Excuse me for too many questions.
I have last question here. You have two setting method for my 'cylinder linear oscillation' examples. I try to figure out the differeces between:

Set FWH control surface to the surface encompassing region in which cylinder translates
Set FWH control surface to the surface encompassing patch of the cylinder translates
But I didn't make it clear. Could you help me with this?
Best,

from libacoustics.

In the first case, FWH control surface is steady and permeable and it encompasses the whole region where cylinder oscillates (cylinder doesn't cross or touch this surface). In the second case the FWH control surface coincides with the surface of the cylinder - it is not permeable, but moves together with the cylinder.

from libacoustics.

The cylinder is in linear oscillation, with inlow velocity of 1m/s, how do I set formulationType, U0, Ufwh respectively?
Best,

Set FWH control surface to the surface encompassing region in which cylinder translates and set fwh (.0 .0 .0);, nonUniformSurfaceMotion false; formulationType Farassat1AFormulation;

Hi，

A little question. If we set nonUniformSurfaceMotion false, shall we set a value for U0? How to set it? U0（0 0 0) for Farassat1AFormulation?

Regards,
Guanjiang

from libacoustics.

The three blades are rotating with rpm 10 and radius 1 m, with inlow velocity of 1 m/s, how do I set formulationType, U0, Ufwh respectively?

Set FWH control surface to patch encompassing these 3 blades, Ufwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

This is true for the dynamic mesh, right? How to simulate the same problem of 3 propeller blades rotating, but for rotation rather than using dynamic mesh, I am using MRF to simulate the effect of rotation. What will be the values of U0, Ufwh?

I would really appreciate the help.
Regards,
Chakshu

from libacoustics.

The three blades are rotating with rpm 10 and radius 1 m, with inlow velocity of 1 m/s, how do I set formulationType, U0, Ufwh respectively?

Set FWH control surface to patch encompassing these 3 blades, Ufwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

This is true for the dynamic mesh, right? How to simulate the same problem of 3 propeller blades rotating, but for rotation rather than using dynamic mesh, I am using MRF to simulate the effect of rotation. What will be the values of U0, Ufwh?

I would really appreciate the help.
Regards,
Chakshu

In this case, U0 may be zero, and Ufwh may be set the rotating speed.

from libacoustics.

The three blades are rotating with rpm 10 and radius 1 m, with inlow velocity of 1 m/s, how do I set formulationType, U0, Ufwh respectively?

Set FWH control surface to patch encompassing these 3 blades, Ufwh (.0 .0 .0);, nonUniformSurfaceMotion true; formulationType Farassat1AFormulation;

This is true for the dynamic mesh, right? How to simulate the same problem of 3 propeller blades rotating, but for rotation rather than using dynamic mesh, I am using MRF to simulate the effect of rotation. What will be the values of U0, Ufwh?
I would really appreciate the help.
Regards,
Chakshu

In this case, U0 may be zero, and Ufwh may be set the rotating speed.

@unicfdlab Can you please confirm this? Is it even possible to use libacoustics with MRF?

from libacoustics.