heat xfer/radcon progress 20oct2006 by john tang benton white

Heat Xfer/RadCon Progress20Oct2006

By

John Tang

Benton White

Heat Xfer Requirements

• Max differential pressure:– Across Clinac=6psi– Across

chiller=4.1psi

• Flow rate across piping=4.3GPM

• 30kW heat dissapation req’d

Heat Xfer Constraints

• Flexible tubing for piping – Fit in confined spaces– Allows for flexible placement of heat xfer

components

• Maintenance considerations– Access to essential components (ie: pump,

reservoir tank) easier– Isolation valves

Vendor Candidates             

VendorContact

InfoDimesion (in)

Weight (lbs)

PowerRequirements

Cooling Capacity

(kW)

Temp range (deg C)

Pressure available

for piping

Liebert1050 Dearborn

DrW 77x H 69.25

x D 38.5 750 2.2 pump kW 25.2 10 to 25 50 psi

  PO Box 29186     460V 60 Hz 3 phase      

 Columbus, OH

43229     208/230V      

  800-877-9222            

ThermoNESLAB 800-258-0830

W 12.6 x H 23.5 x D 20.9 120

115V, 60Hz, 15 Amps 1.25 5 to 35  

 www.thermo.com

/   

or 230V, 50Hz, 8 Amps  

Ambient 13 to 35C  

            55 to 95F  

Pipe Flow Analysis2

( )2L

L vh f k

D g

_

/

_ _

Lh headloss

f friction factor

Llength diameter

Dk pipebend loss coefficients

Pipe Flow Analysis (cont.)

Pipe Flow Analysis (cont.)

• Use Moody Diagram to find friction factors• Find Reynold’s Number, Re

ReDv

D=DiameterV=fluid velocityρ= fluid densityμ= dynamic fluid

viscosity

Pipe Flow Analysis (cont.)

• Use of headloss calculations can be used to find differential pressure in piping

LhP

hL=headloss in piping

ν= specific volume of fluid

Pipe Flow Analysis (cont.)

• Determine mass flow rate of fluid

m Av V _ _

_

_

m mass flow rate

A area

v fluid velocity

density

V volumetric flowrate

RadCon Calcs

• See excel spreadsheet

RadCon

• Safe operating distance for x-ray dose rate is 9km.

2

1

1( ) ( )p x ray m x ray

mD D

r