Convective heat transfer coefficient for bank of rectangular fins

[cnite]

Hello!

I cannot find any correlation for Nusselt number for a bank of aligned rectangular ( parallelepiped ) fins.
How do I calculate h?
The only idea I have is to use correlation for a bank of tubes (cylinders). My fins are 1x8x10 mm when cross flow is onto 1 mm side.
If I do use bank of tubes, what diameter to use? 1 mm or say (1+8)/2 = 4.5 mm?

Please, help.

Thanks

 

[hacksaw]

several heat transfer text and chemical handbooks have what you need, but you have to look