Differential Water Pressure:

dP = 5*10^(-5)*L*W^(1.75)/d^1.25

The factor converts pascal to bar.
L=length in meters.

w = V/A 

this is the water flow per unit surface.
The flow V in liters per second is given from 
the mass flow M (this Kg per min): 

M = P/(Cm*dT)      [Kg/min]


where P the power, P=IR^2  [kW]
and Cm = 4187 J/(Kg*K)  the water specific 
heat capacitance. dT=50 C the assumed temperature
gradient.


Example:
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I=390A (for the 110 mm gap magnet)
R20 = 0.109 Ohm
R50 = 0.122 Ohm   water resistance for 50 C

P  = 18.6 kW
M  = 5.33 Kg/min
V  = 0.0444 l/s
w  = 2.26 m/s
dP = 22.9 bar

This pressure would require modification in the 
existing cooling.The 10mm gap magnet gives 
I=290A and dP=8.1 bar which does not require any
modifications.

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