Calculating natural convection coefficient of horizontal base plate finned heat sink

[creading]

Hi All,

I am looking for a point in the right direction on equations for calculating the average h value for a horizontal base plate finned heat sink. Calculations for renolds/nusault/prantl numbers for vertical base plate finned heat sink natural and forced convection are pretty widely available online but I have had a hard time finding something for natural convection of a horizontal base plate. Maybe I am not searching the right words, but I have been scouring the web and scholarly articles that I can freely read and have yet to find something. I have found reference to what heat sink orientations and aspect ratios are best but nothing that actually gives me equations needed to calculate h. I feel like there probably something in my college heat transfer books but those are at work and I am stuck at home for the time being.

Any help is appreciated,

Thanks!

[Kelly_Bramble]

There are many webpage resources here that may come close to what you're looking for.

https://www.engineersedge.com/heat_t...le_content.htm

[Cragyon]

Horizontal Heated Plate Facing Up Equation and Calculator

https://www.engineersedge.com/heat_transfer/horizontal_heated_plate_facing_up_13969.htm