Conjugate Heat Transfer Analysis on a graphics card.

1. OBJECTIVE

To perform a steady-state conjugate heat transfer analysis on a model of a graphics card.

2. MODEL

3. BOUNDARY CONDITIONS

Inlet velocity: 6m/s

Heat generation: 7.8125e+07 W/m^3

Materials used for the different component:

• Processor: gold
• Fins: copper
• Base: aluminium

4. CASE 1: BASELINE MESH

4.1 MESHING:

Number of nodes: 40107

Number of elements: 191896

Given Element Size:

• Processor: 1.5mm
• Fins: 1.5mm
• Base: 1.5mm
• Enclosure: 8mm

4.2 CONVERGENCE PROOF:

4.3. RESULTS

4.3.1. TEMPERATURE CONTOUR:

4.3.2. VELOCITY CONTOUR:

4.3.3. WALL HEAT TRANSFER COEFFICIENT:

5. CASE 2: REFINED MESH

5.1. MESHING:

Number of nodes: 46448

Number of elements: 217462

Given Element Size:

• Processor: 0.5mm
• Fins: 1mm
• Base: 1mm
• Enclosure: 6mm

5.2 CONVERGENCE PROOF:

5.3. RESULTS

5.3.1. TEMPERATURE CONTOUR:

5.3.2. VELOCITY CONTOUR:

5.3.3. WALL HEAT TRANSFER COEFFICIENT:

6. CONCLUSION:

• The processor, fins and the base are the areas focussed on to refine the mesh.

• The maximum temperature attained by the processor for case 1 is 327k and for case 2 is 326k. Therefore the temperature goes up to 327k on the processor.

• The maximum velocity attained is 7.35m/s which is very close to the given velocity.

• From the temperature contour, it is clear that the temperature on the fins is almost equal to the temperature on the processor. This is an ideal condition because fins take almost all the heat generated from the processor. Better heat transfer along with increased surface area improves cooling.

• The wall heat transfer coefficient for case 1 is 818.6W/m^2 K and for case 2 is 965.2W/m^2 K.

• The potential hotspots on the model are the processor, fins and the contact region between processor and base.