O.K. I needed abreak anyway.

To determine which type of flow exists calculate the following:

Flow rate of the fluid in GPM - Q

Specific gravity of the fluid - G

Pipe inside diameter in inches - D

Fluid viscocity in centepoise - V

Use the following equation to determine the REYNOLDS NUMBER:

REYNOLDS NUMBER = RE = [3160 x Q x G] / [D x V]

Flow conditions with a Reynolds Number greater than 4000 is fully developed turbulent flow. A Reynolds Number less

than 2000 is laminar flow. It requires a Reynolds number greater than 4000 to maintain accuracy.

.................................................. ..........

So we set up the equation to find a flow rate (Q) for a given tube to maintain turbulent flow.

We will assume our numbers are for water. Wort will be very close to this and if anything would trend to nmore turbulent flow.

G = 1 g/cm3

V = 1.0020 cP

RE = 4000

D = desired tubing

Q (gpm) = [4000 x D x V] / [3160 x G] = [4000 x D x 1.0020] / [3160 x 1]

Q (gpm) = [4008 x G] / 3160

so... for a 1/2" diameter tube

Q (gpm) = [4008 x 1/2] / 3160 = 0.634 gpm

This means in order to maintain a turbulent flow in a perferctly straight pipe with a 1/2" diamter, the water must be flowing at .634 gallons per minute. Add the turns we have in our chillers and that number drops significantly.

for 5/8" tubing Q = 0.793 gpm.

Basically, we always have turbulent flow so extra baffles are just a waste and are slowing down fluid flow.

:EDIT: I posted this up in my blog for easy reference.

http://blogs.homebrewtalk.com/Boerde...in_my_chiller/