What does the .pch file contain in the case of a modal analysis?

Altair Forum User

Hi,

 

I did a modal analysis of a 2d plate. I generated a .pch file. Now if I open this file in notepad, I see three columns of data for every mode. 

Are these columns the x,y,z coordinates of the corresponding modeshape? I am asking this because I would like to plot the modeshape in MATLAB. 

I tried plotting it but I did not get a proper shape. 

At first I thought that every row corresponds to the coordinates of a node in the mesh.

But later I observed that for every mode, the number of rows in the notepad file is different. This is what made me doubt about it. 

So what exactly does a pch file contain in the case of a modal analysis?

 

It would be of great help if you can suggest me any other way to plot modeshapes in MATLAB using some result file from my analysis in Hyperworks.

 

 

regards,

Vachan

 

Altair Forum User

Hi @Vachan

 

Can you share the .pch file, please?

Altair Forum User

Hi @Prakash Pagadala,

 

Did you get the files ?

 

regards,

Vachan

Altair Forum User

Hi @Vachan

 

SOrry for a late reply. Some how I lost this question.

 

So, what you see in punch file are the eigenmodes and vectors.

Altair Forum User

What are the three columns in the punch file?

Are they x,y,z coordinates? 
 

 

regards,

Vachan

Altair Forum User

Hi vachan,

 

they are the Eigen vectors

Altair Forum User

Ok Thank you so much!

 

regards,

Vachan

Altair Forum User

Hi,

I am sorry but an eigen vector is a single column for a given eigen value right? So how do i interpret these three columns (listed for every frequency) inside the .pch file?

 

 

regards,

Vachan