×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

#### Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

(OP)
Hi

Or for a simpler method, use ABAQUS/CAE V6.6 (which was released about 5 months ago). You can provide a Python expression as your "Analytical Field" and then use this as the spatial distribution for the load.

(OP)
Hi
I looked in the documentation how to use DLOAD under subroutine option, but I still didn't quite understand how to write that subroutine.  Can you help me to start with this DLOAD subroutine, for example, you have a square box 1 x 1 meter and nonuniform loadings will be applied on the right side of the box. Let the top be the reference surface starts at zero height and the bottom surface is 1 meter down.  Thus at zero height the pressure will be 0, as the depth increases the pressure at 1 meter depth will be 18 kPa.  So the pressure is function of depth.

Thank you very much

Presmably you don't have 6.6?

This is your model, with pressure varying from 0, at y=0, to 18 model units, at y=-1 model distance, on the RHS of the model. Let's say that is side 2 of the elements on that RHS.
Origin
o--------------           press= 0
|               |     <-
|               |     <--
|               |     <---
|               |     <----
y=-1      --------------    <-----  press=18

So you need in your inp file

which according to the manual "applies a nonuniform pressure on face n with magnitude supplied via user subroutine DLOAD". Here 'ELOAD' is an element set of elements adjoining that RHS.

1 COORDS,JLTYP,SNAME)
C
INCLUDE 'ABA_PARAM.INC'
C
DIMENSION TIME(2), COORDS (3)
CHARACTER*80 SNAME
Y = COORDS(2)
C Interpolate to find distributed load according to y:
F = -18*Y
RETURN
END

(OP)
Hi

Thank you very much for your help mrgoldthorpe....
I really appriciated that

(OP)
Hi mrgoldthorpe

I just got abaqus 6.6-3 yesterday, and I tired to use analysis field to create nonuniform load.  In the analysis field, the math equation would be Y*-18 to have pressure varying with depth from 0 to -1, but how do you define your magnitude when you select the right side of the rectangle box and pressure and spatial field.  How would abaqus know that is pressure = Y*-18 and how about the magniture just use 1.

I'm not sure what you tried, but it should be pretty easy:
1. Create your analytical field (Field-1) and the expression should be Y*(-18.0)
2. Create a pressure load on the appropriate face with magnitude 1 and in the "distribution" pull-down select "Field-1"

The magnitude (=1)that you provide will by factored by the value of the expression at the given local value of Y.

(There is no need for user subroutines with this method)

#### Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

#### Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

#### Resources

eBook - The Future of Product Development is Here
Looking to make the design and manufacturing of your products more agile? For engineering and manufacturing organizations, the need for digital transformation of product development processes just became more urgent than ever so we wanted to share an eBook that will help you build a practical roadmap for your journey. Download Now

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!