Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

Obtaining Mass and Stiffness Matrices from HyperMesh Model

I am looking to obtain the mass and stiffness matrices of Hypermesh models in order to manipulate them in Matlab for structural dynamics problems. Does anyone know of an output that Altair may have built in or possibly a simplified method of obtaining these?

Find more posts tagged with

English

HyperCrash

Accepted answers

All comments

Altair Forum User

Hi,

Please use PARAM, EXTOUT in control cards to write out reduced stifness and mass matrix to an external file.

EXTOUT has two formats DMIGPCH and DMIGBIN which wirtes to .pch and .dmg formats respectively.

Go to Analysis>> Control cards>> PARAM, EXTOUT (DMIGPCH) to activate the card.

This will write a reduced mass and stiffness matrices in .pch format in the working directory.

You can also try PARAM, POST, -5 will write the stiffness and mass matrices to the .k.op2 and the .m.op2 files, respectively

Altair Forum User

Hi,

where can I find this option in HyperCrash? Is there any possibility to get the nodal forces in an ASCII file?

Thanks!

Altair Forum User

Hi,

I am facing the same problem. The method for calculating the .k.op2 and .m.op2 files seems the most straightforward to me. But how can I read obtained binary files?

Thanks for you help,

Matej

Rahul Rajan_21763

You would need to open the result files (H3D/OP2) which are binary files in HV.

Regards

Rahul R

Altair Forum User

Can you please be more specific. How to view or load the mass and stiffness matrices, based on the op2 files in HV?

Greetings,

Matej

Altair Forum User

All,

This feature maybe available soon for RADIOSS solver.

LOKESH KATARI

how to calculate stiffness matrix of a body in HM opti

thank you

Altair Forum User

Hi Lokesh,

You can output the stiffness matrix. Please search for the same in the forum for related links.

LOKESH KATARI

can we calculate the rotational stiffness in hypermesh?

Diogo Ferreira

I've done those steps and there's no file in working directory? why?

FaroukM

You would need to open the result files (H3D/OP2) which are binary files in HV.

Regards

Rahul R

There is any other option to export *.m.op2 / *.k.op2 as an ASCI file ?

David Vásquez

Hi,

Please use PARAM, EXTOUT in control cards to write out reduced stifness and mass matrix to an external file.

EXTOUT has two formats DMIGPCH and DMIGBIN which wirtes to .pch and .dmg formats respectively.

Go to Analysis>> Control cards>> PARAM, EXTOUT (DMIGPCH) to activate the card.

This will write a reduced mass and stiffness matrices in .pch format in the working directory.

You can also try PARAM, POST, -5 will write the stiffness and mass matrices to the .k.op2 and the .m.op2 files, respectively

Hi, i tried both options but i only get the stiffness matrix, do you know why?

Vinícius Santos_20886

Hi,

Please use PARAM, EXTOUT in control cards to write out reduced stifness and mass matrix to an external file.

EXTOUT has two formats DMIGPCH and DMIGBIN which wirtes to .pch and .dmg formats respectively.

Go to Analysis>> Control cards>> PARAM, EXTOUT (DMIGPCH) to activate the card.

This will write a reduced mass and stiffness matrices in .pch format in the working directory.

You can also try PARAM, POST, -5 will write the stiffness and mass matrices to the .k.op2 and the .m.op2 files, respectively

Sorry, David Vásquez.

But it did not work.