air-cooled heat sink for a CPU

1. Define the Problem

• Geometry: Create the heat sink model, including fins, base, and the CPU die (heat source).
  
  

• Material Properties: Define thermal conductivity, specific heat, and density for all materials (copper, aluminum, etc.).
  
  

2. Set Up the Physics

• Use the Heat Transfer in Solids and Heat Transfer in Fluids modules.
  
  

• Heat Source: Apply heat generation in the CPU region (often modeled as a heat flux or volumetric heat generation).
  
  

• Convection: Define convective boundary conditions on the heat sink surfaces exposed to air. Use fluid flow simulations to model air movement if necessary.
  
  

3. Meshing

• Use finer meshes around the CPU and heat sink surfaces to capture temperature gradients accurately.
  
  

• For complex geometries, consider using adaptive meshing for better accuracy.
  
  

4. Boundary Conditions

• Fixed Temperature or convective heat flux at the heat sink-air interface.
  
  

• Heat Flux at the CPU interface representing the power dissipation.
  
  

5. Solve the Model

• Choose a steady-state or transient solver depending on whether you’re analyzing continuous operation or transient thermal behavior.
  
  

6. Post-Processing

• Visualize temperature distribution, heat flux lines, and thermal gradients.
  
  

• Identify hotspots and optimize the design (e.g., fin thickness, spacing, or material).
  
  

Optimization Tips

• Use the Parameter Sweep feature to optimize variables like fin height, spacing, and base thickness.
  
  

• Consider Design Optimization modules if you want to automate the process.