I'm looking at DIY projects where a COB LED is cooled by an all-in-one CPU liquid cooler, however the contact area in a CPU heatsink will only fit one high-power LED. I'm considering how I could use several, perhaps less powerful LEDs with a single heatsink.
Is it feasible to mount LEDs on a larger copper plate, which is then tightly fixed to the heatsink (screws + paste, or thermal adhesive)? What can be expected from and what should be considered for this solution?
UPDATE - already got a great answer with general principles, but here are the specific numbers for my current project:
- 4 COB LEDs of 25W, 19x19mm large. Will be at least 70mm apart because of lenses.
- Cooler is a Liquid Freezer 120 with a surface diameter of 60mm and recommended max TDP of 250W.
- Based on the answer below I'm considering a 6mm thick aluminum disc with a diameter of 144mm, for mounting the LEDs on and then attaching to the cooler.