I use the aforementioned Denis Moss myself. But you don't necessarily have to buy it. I allow fabricators to use any method that is based on sound engineering and takes account of all of the below...
(Other manufacturers' in-house methods will essentially all follow the same basic Good...
TEMA RCB-4.62 sets the limits for RHO.v^2. You use the formulae in RGP-RCB-4.62 to calculate the two areas (shell and bundle) based on where you are intending to put the impingement plate, and its diameter. Use each calculated area separately and in turn to calculate v and thus RHO.v^2. If it...