How to calculate shell's hydraulic diameter of 30 degree pitch on Shell & Tube Heat Exchanger ?

[miftahazhar]

Hello.. I need help because i want to calculate shell's convection coefficient. but this exchanger has 30 degree pitch tube arrangement. I've read Kern's Process Heat Transfer book and Coulson's Chemical Engineering book but they only provide for 60 degree and 90 degree pitch tube arrangement. Is thhere any formula to calculate 30 degree pitch shell's hydraulic diameter ? Also what is the source of the formula..

hydraulic diameter to calculate reynold number then to calculate convection coefficient (h). i am using kern method

Thank you so much

 

[chicopee]

Is the fluid under free or forced convection?

 

[chicopee]

Also is the fluid being heated or cooled?

 

[georgeverghese]

Suspect 30deg triangular pitch is essentially rotated 60deg triangular pitch. As far as i know, the rotated pattern has the same htc and dp as the non rotated pattern, as described by the Bell - Delaware method for calculating shellside htc and pressure drop, which may be found in Perry Chem Eng Handbook 7th edition pages 10-26 onwards. There is some difference though between 90deg sq pitch and 45deg sq pitch for shellside htc.