Introduction to USDFLD and VUSDFLD Subroutine
Using Abaqus USDFLD and VSDFLD enables you to simulate models in which the properties of their materials are related to some parameters or conditions. For example, modeling an adhesive joint whose cohesive damage properties are related to a parameter that is not in Abaqus GUI. Analyzing soil that the elastic modulus is related to its depth is a practical example. You will learn how to code these two subroutines as well as the differences between them. In addition, you will be able to change one of them to another. To sum up, using the USDFLD subroutine, there will be no limitation for you to simulate models containing variables function to other parameters. In addition, we explain how to get access to the interfaces of subroutines, essential settings in GUI, get familiar with each subroutine’s parameters, etc.
Abaqus USDFLD and VSDFLD have a very broad scope, and in general, you can use these two subroutines whenever you a parameter in the software material environment that you want to rely on another variable. The difference between the two subroutines is in their solver, where Abaqus standard and Abaqus Explicit solvers use USDFLD and VUSDFLD, respectively. You will learn about how to connect Abaqus and subroutine, as well as an overview of subroutine writing in Abaqus.
Workshop 1 Simulation of elastic properties of soil in different depths with USDFLD subroutine :
In this workshop, we will use a simple example to use the USDFLD subroutine. We compare two Abaqus GUI and subroutine methods for simulating soil with changing modulus of elasticity at different depths under compressive loading. At last, we compare the results in both models.
Workshop 2 analyzing a crack path in Spherical FGM:
We will model a functionally graded material (FGM) with a crack on its spherical geometry in this workshop. The USDFLD subroutine is used since we wanted to simulate this by the Abaqus standard. In this model, pressure is applied from the inner part of an empty sphere, and the distribution of stress in this sphere is discussed. Further, the XFEM method is used to define the material for crack and to locate a crack in the Interaction module. In this exercise, we’ve also discussed parameters related to crack analysis and finally checked the results.
Workshop 3 composite shell plane explosion with a sticky connector in the layers:
In this workshop, the main subject is to use the VUSDFLD subroutine to damage an explosive structure as we used Abaqus Explicit solver. In this model, we show how to use the VGETVRM subroutine in the VUSDFLD subroutine. Furthermore, we explain utterly how to define different possible conditions based on damage numbers in subroutines of the VUSDFLD. Finally, view the deflection results and other variables in composite layers.
The Abaqus user subroutine allows the program to be customized for particular applications unavailable through the main Abaqus facilities. You should write a user subroutine if you could not run your analysis by ABAQUS built-in models for materials, loads, properties, elements, etc., for example, if you need to model a user-defined nonlinear stress-strain relation, which is not provided by Abaqus, then look for UMAT user subroutine. A more advanced subroutine is USDFLD, which allows the creation of user-defined fields to simulate models in which the properties of their materials are related to some parameters or conditions. If it is your first time writing a subroutine like USDFLD, please read the Start Writing an Abaqus Subroutine: Basics & Recommendations article. After reading this post and watching this tutorial’s demo video, you will definitely decide to save time in Abaqus modeling and get this USDFLD training package. If you have questions, ask here on our live chat on the left side of this page.
cheng uangli –
The workshops in this package were so rich. I could not find them somewhere else.
wang zhang –
I am a mechanical engineer and I bought this package. I learned a lot from this package include modeling and simulating FGM and fatigue in various situations.
Thanks CAE Assistnat Team!!
Excellent course. Useful content and explanations, and covers lots of details and recommendations.
Although, naturally, engineering knowledge is fundamental!
I have years of experiences in working with ABAQUS, and I took this course to learn more about the structural analysis. Course developer is very generous !! but I expect more example.
the course were well defined and each of he sections were explained good way to make user understand about the concept.