Abaqus Thermal Analysis Workflow

Heat transfer analysis for steady-state or transient temperature distribution. Use when user needs temperature field without mechanical stress.

When to Use This Skill

Route here when user mentions:

• "Heat transfer analysis", "temperature distribution"
• "How hot will it get?", "thermal analysis"
• "Conduction", "convection", "radiation"
• "Heat sink design", "cooling analysis"
• "Steady-state temperature", "transient heating/cooling"

Route elsewhere:

• Thermal stress (temperature causing deformation) →

  /abaqus-coupled-analysis

• Just stress analysis →

  /abaqus-static-analysis

• Temperature as initial condition only →

  /abaqus-field

Prerequisites

Before thermal analysis:

1. Geometry defined
2. Thermal conductivity (k) - required for all thermal analysis
3. For transient: also need density (ρ) and specific heat (cp)

Workflow: Thermal Analysis

Step 1: Understand User's Goal

Ask if unclear:

• Steady-state or transient? Final equilibrium vs temperature over time?
• Boundary temperatures? Fixed temperature surfaces?
• Convection? Film coefficient and ambient temperature?
• Heat sources? Applied heat flux or internal heat generation?

Step 2: Choose Analysis Type

User Wants	Analysis Type
Final equilibrium temperature	STEADY_STATE
Temperature vs time history	TRANSIENT
Cool-down or heat-up time	TRANSIENT
Just the end result	STEADY_STATE

Decision rule: Use steady-state unless user needs temperature history or time-dependent behavior.

Step 3: Define Thermal Material Properties

Property	Required For	Units (SI-mm)
Conductivity (k)	All thermal	mW/(mm·K)
Specific heat (cp)	Transient	mJ/(tonne·K)
Density (ρ)	Transient	tonne/mm³

Common materials (SI-mm units):

Material	k	cp	ρ
Steel	50	5.0e11	7.85e-9
Aluminum	167	9.0e11	2.70e-9
Copper	385	3.85e11	8.96e-9

Step 4: Apply Thermal Boundary Conditions

BC Type	Use For	Required Inputs
TemperatureBC	Fixed temperature surface	Temperature value
FilmCondition	Convection to ambient	Film coeff, sink temp
SurfaceHeatFlux	Heat input	Flux magnitude (mW/mm²)
RadiationToAmbient	Radiation cooling	Emissivity, ambient temp
BodyHeatFlux	Internal heat generation	Volumetric heat rate

Minimum requirement: At least one temperature BC or heat flux boundary.

Step 5: Create Heat Transfer Step

Parameter	Steady-State	Transient
response	STEADY_STATE	TRANSIENT
timePeriod	1.0 (arbitrary)	Actual duration (s)
initialInc	-	Start increment
maxInc	-	Largest allowed increment
deltmx	-	Max temp change per increment

Step 6: Mesh with Heat Transfer Elements

Element	Use
DC3D8	Standard 8-node hex (recommended)
DC3D4	4-node tet (for complex geometry)
DC3D20	20-node hex (high accuracy)

Note: Heat transfer elements (DC*) are different from structural elements (C3D*).

Step 7: Run Analysis and Extract Results

Request these field outputs:

• NT - Nodal temperature
• HFL - Heat flux vector
• RFL - Reaction heat flux
• HFLM - Heat flux magnitude

Validation Checklist

After analysis, verify:

• Temperature range is physically reasonable
• Heat balance: flux in ≈ flux out (steady-state)
• No unexpected hot/cold spots
• Transient: temperature stabilizes by end of analysis

Troubleshooting

Problem	Likely Cause	Solution
Temperature oscillation	Large increments in transient	Reduce maxInc or deltmx
Non-physical temperature	Unit mismatch	Verify k, cp, ρ units
No heat flow	Missing BC or bad region	Check boundary conditions
Negative temperature (Kelvin)	Bad setup	Review initial conditions

Related Skills

• /abaqus-coupled-analysis

  - Thermal + structural (thermomechanical)

• /abaqus-material

  - Thermal material properties

• /abaqus-field

  - Initial temperature fields

Code Patterns

For API syntax and code examples, see:

• API Quick Reference
• Common Patterns
• Troubleshooting Guide