2. I have been tasked with doing some hardware intensive Solidworks simulation that will require a large
amount of time to complete. To speed up the process I have overclocked my CPU so that it is producing
a heat power of 150 watts. I am worried that the stock heat sink will not be able to keep up with the
heat produced and will overheat. The threshold for CPU deterioration is 75 C (348 K). A design for a
proprietary liquid cooling system has been designed and needs to be analyzed to determine if it will be
able to keep up with the increased heat from overclocking.
Find
- Time at which the stock heat sink reaches 75 C
- Power the stock heat sink is able to dissipate
- Power water cooling system is able to dissipate
Heat Sink
Figure 1 Heat Power of 150 W applied to the bottom of the heat sink
Figure 2 Initial temperature set to 293.2 K
3. Figure 3 Convection of 25W/(m^2.K) and 293.2K set as the bulk ambient temperature
Test # 1: Thermal Study - Transient: 250 Seconds, 25second interval
Mesh: 0.125” Global Mesh
Figure 4 Max Temperature of 74.89 C
4. Figure 5 Heat power out of the heat sink is 113.34 watts
Test # 2: Thermal Study – Transient: 250 Seconds, 25second interval
Mesh: 0.0625” Global Mesh
Figure 6 Max Temperature of 74.87 C, the results have converged
5. Figure 7 Heat power out of the heat sink is 113.41 watts, the results have converged
Water Cooling
Lids modeled and applied to entrance and exit
Figure 8 External flow test, Heat conduction in solids and time dependent with 250 seconds at 25 second intervals
6. Figure 9 water and air selected for fluids
Figure 10 Copper selected as material
All other settings left as default
7. Figure 11 Heat generation of 150w applied to bottom of water block
Figure 12 Inlet mass flow of 0.003kg/s applied to the inlet
8. Figure 13 outlet of radiator set to atmospheric pressure
Figure 14 Boundary condition of a real wall applied to the radiator with a convection of 25W / (m^2.K)
9. Figure 15 Fluid subdomain applied to inside of water block and piping through radiator
Global Goal of Heat power transfer applied
Test #1: Flow Simulation
Time Step: 5 seconds
Figure 16 Mesh used for first test
10. Figure 17 the heat power transfer of 148.529 watts out of the system
Figure 18 Temperature flow lines, Max temperature of CPU is 320.41 K
Figure 19 Water block out temperature measured in location as shown. Inlet and outlet temperature measure with surface
parameters at Inside of lids
11. Figure 20 Cut plot set in middle of flow of water block. Flow of heat through the water block with water starting at 293.2 K and
exiting at 313.92 K
Figure 21 Cut plot set in middle of flow of water block. Water enters at 313.92 K and exits at 302.18 K. The radiator dissipates
11.74 K
12. Test #2: Flow Simulation
Mesh: set at 6
Time Step: 25 seconds
Figure 22 the heat power transfer of 152.157 watts out of the system
Figure 23 Temperature lines flowing through system. Max temperature of CPU is 320.41 K
13. Figure 24 Flow of heat through the water block with water starting at 293.2 K and exiting at 312.73 K
Figure 25 Water enters at 312.73 K and exits at 301.79 K. The radiator dissipates 10.94 K
14. Test #3: Flow Simulation
Mesh: set at 6
Time Step: 5 seconds
Figure 26 the heat power transfer of 148.621 watts out of the system
Figure 27 Temperature lines flowing through system, Max temperature of CPU is 320.41 K
15. Figure 28 Flow of heat through the water block with water starting at 293.2 K and exiting at 311.79 K
Figure 29 Water enters at 311.79 K and exits at 301.81 K. The radiator dissipates 9.98 K
16. Test #4: Flow Simulation
Mesh: set at 6
Time Step: 3 seconds
Figure 30 the heat power transfer of 147.429 watts out of the system
Figure 31 Temperature flow lines through the water block. Max temperature of CPU is 320.41 K
17. Figure 32 Temperature flow lines through the radiator
Figure 33 Water block reaches a max temperature of 320.41 K with the water entering at 293.2 K and exiting at 312.25 K
18. Figure 34 Water enters at 312.05 K and exits at 301.94 K. The radiator dissipates 10.11 K. The results have converged.
The liquid cooling system is able to dissipate 147.429 watts out of the system compared to 113.41 watts
the stock heat sink is able to dissipate. The heat sink allows the CPU to rise to 75 C within 250 seconds
while the water cooling system only allows the CPU to reach 47.41 C. The water cooling system will
allow the CPU to run for a longer time without letting the temperature rise to a dangerous level.
