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Hi Abhi,

 

Yes, I need the .out file and if possible please share the model file. 

 

Looks like there is some incompatibility in the model. 

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Guest

Hi Abhi,

 

I got the model but I see frequency cards in it which has nothing to do with impact.

 

Please correct me if I am wrong. 

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@Prakash Pagadala,

Yes I have gone through that stuff, theoretically, it's okay, but while using the cards in the solver, it is not of much help...

 

Can you just check the loadsteps in the model and suggest what type of analysis and other card images be used...........

 

The file is already shared to you.............. 

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Guest

Hi Abhi,

 

Yes, few questions:

 

Where do you want to get the pressure level?

 

What is the load on the ball?.. You can provide a spcd but the value of the same is required!!?

 

The location and all is required. 

 

 

 

 

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@Prakash Pagadala

Initially I was planning to have initial velocity on the ball that hits the rigid wall...

But because you suggested, we changed that to velocity on the wall... But still I would prefer it otherwise

The sound pressure level can be found at any location close the point of hitting...

For infinite acoustic analysis, I will go through the theory once...

 

I was wondering if you could send me the example file...

 

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@Prakash Pagadala,

I just got an idea, how about creating an acoustic cavity around the ball and eliminating air component around itself. Applying air material and properties to it, without any seat component..

 

Still I would require information on setting up the load step for the same.

 

  

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Guest

Hi Abhi,

 

Since impact is not a way in FRF, you can apply enforced displacement or velocity on the ball to calculate responses.

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As per the Altair Help, RADSND card defines grids (microphone locations) where sound levels will be calculated and the locations of the corresponding source (vibrating panels) grids.

 

The RADSND card is however not compsatible with analysis except Frequency response or Transient Analysis...

 

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18 hours ago, Abhi05 said:

As per the Altair Help, RADSND card defines grids (microphone locations) where sound levels will be calculated and the locations of the corresponding source (vibrating panels) grids.

 

The RADSND card is however not compsatible with analysis except Frequency response or Transient Analysis...

 

@Prakash Pagadala,  did you find any help for Loadsteps... or if even Optistruct is compatible enough to carry out Radiated Sound Analysis??

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@Abhi05

 

I have shared an example file for analysis with infinite elements.

 

Please go through the example and model accordinly. Make sure the outer elements are of Infinite element type. 

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@Prakash Pagadala,
I got your file and I checked it also, 

I see that 1. The material for sphere is non existing.

2. There is a property named: Undefined_1, which is linked to component: outer_sphere_interface, for which the card image and  material cards are empty.
3. The output is undefined, I think the SPL, SPOWER and SINTENS output form will suit our requirement.
4. The SPC and SPCD loadcollectors are also empty, if you can explain me their purpose, maybe I can define them and run the simulation.
5. I think there is no material defined for the sphere itself, the material is defined for the sphere shell and the outer covering materials.. But that might not be a problem anyways, I can define that...

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Guest
20 minutes ago, Abhi05 said:

1. The material for sphere is non existing.

 

core material is AL and for all fluid mesh MAT10 is used

21 minutes ago, Abhi05 said:

2. There is a property named: Undefined_1, which is linked to component: outer_sphere_interface, for which the card image and  material cards are empty.

Looks like there is some problem with the file. I will share the .hm file instead

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@Prakash Pagadala

There are two load collectors, SPC and SPCD; as far as I understood, SPC is containing Velocity;
But SPCD, I cannot understand....

 

Also, on running the file you sent, I see no results, the ball stands at its own place

Edited by Abhi05
Adding more details

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Guest

Hi Abhi,

 

SPC is constraints and SPCD is used for velocity.

 

Please refer to RLOAD card. 

 

On 4/27/2018 at 6:36 PM, Abhi05 said:

Also, on running the file you sent, I see no results, the ball stands at its own place

I used minimal velocity. Increase the velocity and check the results. 

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@Prakash Pagadala

I increased the ball velocity still it does not move, rather it vibrates in its own location,

I think that you have introduced a Frequency excitation load too as far as I understand. (Because we do not need an excitation, we need a simple phenomenon where the ball hits and produces sound..)

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35 minutes ago, Prakash Pagadala said:

One way is to get the impact load (convert to pressure load) and use the same as load in acoustic analysis 

@Prakash Pagadala,

So for this I think we need to remove the ball and convert it's impacting status to values and generating a force of equivalent magnitude on the plate and then generate the frequency response analysis??

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