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[latexman]

You may want to widen your investigation of viscosity vs. shear rate to viscosity vs. shear rate vs. temperature. It depends on the rise in temperature in the heat exchanger and the viscosity-temperature sensitivity of the slurry.

A logical next step would be to fit the data collected to a rheological model, such as the power law, with a temperature correction term, possibly based on the Andrade correlation. If you are lucky, you'll end up with a single equation of viscosity = function of shear rate and temperature, which will be invaluable in sizing either type heat exchanger.

It would take more effort to explain the rest of what you need than I'm willing to give at the moment, so I am going to give you three references to get and study. They hold key information you need to size those two heat exchangers. I hope you have access to a good engineering library!

The series "Designing for Non-Newtonian Fluids" by M. H. Wohl in Chemical Engineering magazine appeared in the Jan. 15, Feb. 12, Mar. 25, Apr. 8, May 6, and June 3, 1968 issues.

A. H. P. Shelland's "Non-Newtonian Flow and Heat Transfer" by Wiley, New York, 1967.

Bird, Stewart, and Lightfoot's "Transport Phenomenon". This one is still in publication!