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[Sadananda Konchady]

This topic is about heat transfer and line sizing for Non-Newtonian fluids, particularly with fluid index "n" less than 1, which arises when solid content in the liquid is relatively high.

One reference with worked out examples on this topic, which I could find was:

Ref: A.T. Jackson, and J. Lamb.
Calculations in Food and Chemical Engineering
Macmillan Press (1981)

A pressure drop correlation given was:

D * DelP / ( 4* L) = K * ( 8 * U / D ) ^ n

D = Tube diameter
Del P = Pressure Drop
L = Tube Length
K = Mean Fluid Consistency
U = Tube Velocity
n = Fluid Index

and for heat transfer

Pigford Equation with no natural convection

hm . D / k = 1.75 * del ^0.3333 * Gz ^0.3333
del = (3n+1)/4n
Graetz Number = Gz = W.Cp/kL
k = Liquid Thermal Conductivity
W = Mass Flow Rate
Cp = Liquid Specific Heat
Gz > 20
n > 0.1
Accurate within +/-15% for Gz>100

Pressure drop or line size calculations seem to be practical with the pressure drop correlation.

However, the situation with heat transfer correlations is more uncertain. Are there better correlations for heat transfer in the tube side?

Any references in the form of recommended books, weblinks, or software for thermal design of shell and tube heat exchangers / plate heat exchangers is welcome.



Thank you,

Escape