---
type: concept
title: "Abaqus Spatial Model Definition"
complexity: intermediate
domain: computational-mechanics
created: 2026-05-29
updated: 2026-05-29
address: c-000073
aliases:
  - Abaqus model definition
  - Abaqus node and element definition
  - Abaqus spatial modeling
tags:
  - concept
  - finite-element-method
  - abaqus
  - modeling
status: current
related:
  - "[[Abaqus-Analysis-User-s-Guide-Volume-I|Abaqus Analysis User's Guide Volume I]]"
  - "[[Abaqus Input File Syntax]]"
  - "[[Abaqus Element Library]]"
  - "[[Isoparametric Finite Elements]]"
  - "[[Finite Element Program Implementation]]"
sources:
  - "[[Abaqus-Analysis-User-s-Guide-Volume-I|Abaqus Analysis User's Guide Volume I]]"
---

# Abaqus Spatial Model Definition

## Definition

Abaqus spatial model definition is the practical specification of the finite element mesh and model topology: nodes, elements, sets, coordinate systems, sections, distributions, and optional model-level mass or display definitions.

## How It Works

Nodes are assigned numbers and coordinates, optionally in local coordinate systems. Node numbers are unique within their scope, and local coordinates are transformed into the working system when the model is read. Node sets provide reusable groups for constraints, loads, interactions, and output requests.

Elements are defined by element number, element type, and connectivity. Element type selects the formulation from the [[Abaqus Element Library]], while connectivity maps the element's local topology to node numbers. Element sets group elements for section assignments, material behavior, output, surfaces, or load definitions.

The guide also covers generated, copied, filled, and mapped node or element definitions, plus distributions, nonstructural mass, mass adjustment, display bodies, and integrated output sections. These features turn the mesh into an analysis-ready model rather than just a list of coordinates and connectivities.

## Why It Matters

Spatial model definition is where the mathematical finite element discretization becomes concrete. It determines the geometry, topology, degrees of freedom, element formulation, and grouping structure that later procedures and output requests operate on.

## Connections

- [[Abaqus Input File Syntax]] gives the keyword grammar used to enter the spatial model.
- [[Abaqus Surface and Assembly Modeling]] builds contact, loading, and reusable part-instance structure on top of nodes and elements.
- [[Finite Element Modeling and Convergence Checks]] evaluates whether the resulting mesh and idealization are credible.

## Sources

- [[Abaqus-Analysis-User-s-Guide-Volume-I|Abaqus Analysis User's Guide Volume I]]