So I have a good working circuit, but now I want to maximize the current output to 10 Amps per channel (8 total).
The MOSFETS can handle the current, but no way my current heat sinks are sufficient.
A re-design is okay, but I do so little heat-sink work that I am not sure of the best tool to utilize.
Contracted the manufacturer of the heat-sinks shown, and they had nothing significant to share.
The heat-sinks are not connected to the live output, so their effectiveness is mostly visual )
Wanting to avoid fan, since it may fail too easily. However, fans are truly the best solution that I have ever used.
Suggestions welcome.

 

Maybe this will help:
https://heatsinkcalculator.com/

 

Maybe this will help:
https://heatsinkcalculator.com/

That looks very interesting ... thank you kindly for sharing. Looks like it would cost me $89/month. Have you personally utilized this service yourself? If so, any feedback, review?

 

Another scheme to determine the physical size of the heat sink is to first calculate the power turned into heat, by multiplying the device current by the anticipated voltage drop across the device. Then consult a good electronic component sales company catalog, or even a heat sink manufacturer's catalog, and note the sizes for heat sinks able to handle that much power. Look at the drawings or pictures and you will know what you need. And it is all free.

 

That looks very interesting ... thank you kindly for sharing. Looks like it would cost me $89/month. Have you personally utilized this service yourself? If so, any feedback, review?

Sorry, no. I relied on a manufacturer's advice to find a heat sink suitable for still air.

I was also interested in which way the fan should blow on a typical heat sink. My hunch was it should blow into the heat sink, as this would increase the density and thus convective heat transfer of the air in contact with the sink. The manufacturer confirmed this and didn't even consider using a sucking fan.

 

The air blowing onto the heat sink will need to be filtered, if this is to be a long-term application.

 

If you can anodize the aluminum heat sink that will be better than just bare aluminum. I didn't used to think that it mattered, but I had a boss once do a side by side comparison between plain aluminum heat sink, black anodized aluminum heat sink, and white anodized aluminum heat sink ... ALL on identical circuit boards. Hands down the black anodized aluminum heat sink performed the best as far as heat dissipation.