A mesh does not define where the structure is supported or which external loads it must carry. In M05 we will turn the free-body diagram into constraints and loads, then check the values stored by MAPDL before solving.
Your mission
You will fully constrain the left end of the beam, distribute a total force of
-1000 N over its right end, and generate a CSV that records the selected regions,
constrained degrees of freedom, and actual sum of nodal forces.
Guiding question: How do you distinguish a total force from a force applied to each node?
Objectives
By completing M05 you will be able to demonstrate that:
- Translate a free-body diagram into regions, degrees of freedom, and force components.
- Apply constraints and loads exclusively on named components.
- Explain what each
ALLmeans inD,ALL,ALL,0. - Maintain a constant resultant force when the number of nodes changes.
- Distinguish selection, nodal system, visualization and results system.
- Read constraints and stored forces using
*GET. - Audit boundary conditions without using reactions or results.
Prerequisites and downloads
- Complete M02 to work with components and selections.
- Complete M04; we will use the first accepted mesh, with 40 elements.
- Remember that
SOLID185has the displacement DOFsUX,UY, andUZ.
05_start.mac— starting point.05_loads_constraints.mac— audited solution.05_bug_hunt.mac— five deliberate failures.05_challenge.mac— mesh independence challenge.05_expected_results.csv— self-checking contract.
How to use this lesson
| Track | Duration | Scope |
|---|---|---|
| Quick win | 30–35 min | Prediction, regions, fixed support and audited load distribution. |
| Complete | 65–70 min | In addition, reference systems, sum of forces, challenge with more nodes. |
Recommendation: run DLIST and FLIST before SOLVE. The intent of the script does not prove
what conditions were actually stored.
Session map
- Mission: objectives, downloads, and a refinement prediction.
- Mental model: boundary conditions as part of the model.
- Demo: apply, list, and audit loads and constraints.
- Bug hunting: empty selections and incorrect load distributions.
- Challenge: same total force with more nodes loaded.
- Mastery: final test that records demonstrated mastery and recommends M06.