MLC
1 mW
Hi All,
Cool stuff. I hope you find time to collect data, CD.
I sometimes manage heat in electronic assemblies at work and have some thoughts...
Air flow through (or around) the sinks will play a major part in their efficacy. The pictured implementation (a dense array) might result in smooth air flow over the sinks (rather than through). If so, not ideal.
I'm guessing you're going for max surface area (good theory). But, half the surface area with turbulent flow through the sinks, could be better than 100% coverage with smooth air flow over the sinks. When sinks are effective, you don't have to worry about 100% coverage since heat will "run" to them. (Heat flow proportional to delta-T)
To address air flow and the contact area (sink-to-hub) issue, you might want to try (1) using long-narrow sinks rather than square, (2) leave a space between them and (3) mount them at alternating diagonals (slight "zig-zag").
Lastly, as Neptronix said, the thermal resistance between the sink and hub (how you fix the sinks) is a primary factor. The combination of narrower sinks plus thermal epoxy would make a very big difference (over squares with foam).
Found these after about two minutes of searching. I didn't look closely; there may be better choices out there...
http://www.digikey.com/product-detail/en/assmann-wsw-components/V5619A/AE10812-ND/3511388
http://www.omega.com/pptst/OB-100_OB-200_OT-200.html
Maybe you'll consider these ideas in one of your experiments. Have fun!
Note: I plan to make my first, 16 mile commute via ebike next week. (1500W, 5T LB and 14S on GT Avalanche)
Best,
MLC
Cool stuff. I hope you find time to collect data, CD.
I sometimes manage heat in electronic assemblies at work and have some thoughts...
Air flow through (or around) the sinks will play a major part in their efficacy. The pictured implementation (a dense array) might result in smooth air flow over the sinks (rather than through). If so, not ideal.
I'm guessing you're going for max surface area (good theory). But, half the surface area with turbulent flow through the sinks, could be better than 100% coverage with smooth air flow over the sinks. When sinks are effective, you don't have to worry about 100% coverage since heat will "run" to them. (Heat flow proportional to delta-T)
To address air flow and the contact area (sink-to-hub) issue, you might want to try (1) using long-narrow sinks rather than square, (2) leave a space between them and (3) mount them at alternating diagonals (slight "zig-zag").
Lastly, as Neptronix said, the thermal resistance between the sink and hub (how you fix the sinks) is a primary factor. The combination of narrower sinks plus thermal epoxy would make a very big difference (over squares with foam).
Found these after about two minutes of searching. I didn't look closely; there may be better choices out there...
http://www.digikey.com/product-detail/en/assmann-wsw-components/V5619A/AE10812-ND/3511388
http://www.omega.com/pptst/OB-100_OB-200_OT-200.html
Maybe you'll consider these ideas in one of your experiments. Have fun!
Note: I plan to make my first, 16 mile commute via ebike next week. (1500W, 5T LB and 14S on GT Avalanche)
Best,
MLC