scalar mass

Karthic_22061

Hi ,

To include the the effect of inertia... scalar mass is sufficient in model or should i call upon any special cards ?

 

Is it possible to create Cmass(scalar mass) elements on the grid points(nodes) of shell element as the same way in CONM2.

 

By doing so. I got an error

*** ERROR # 1243 ***
  Duplicate ID 58391 in SPOINT data.

 

Where as its working fine with concentrated (CONM2) mass.

 

Rahul Rajan_21763

I think that CONM2 should be used for your model. You can not simply pick the structural grids in the model to create CMASS because, if you do that, internally generated spoint from CMASS will have the same id as the structural grids.

Karthic_22061

Hi Rahul,

Thanks for the reply.

Altair Forum User said:

@jahnavi

 

CMASS1 is a scalar mass connection where as CONM2 is  concentrated mass in rigid form.

 

Scalar mass elements are useful for representation of inertia properties

 

how about inertia properties when using CONM2.

In my model the component( along with mass elements) is moving at certain angular velocity. I need to study the effect on sudden stop. Can i use CONM2, if so what about the inertia ?

Karthic_22061

Hi Rahul,

If i can not simply pick the structural grids in the model to create CMASS.

what should be picked to create the CMASS ?

Rahul Rajan_21763

Create a CONM2 element and then card edit the element to add the inertia values.

<?xml version="1.0" encoding="UTF-8"?>

AJM

Hello Rahul,

 

How to define principle axis of direction to the mass.