## THERMAL SCIENCE

International Scientific Journal

### A FRACTIONAL MODEL FOR TIME-VARIANT NON-NEWTONIAN FLOW

**ABSTRACT**

This work applies a fractional flow model to describe a time-variant behavior of non-Newtonian substances. Specifically, we model the physical mechanism underlying the thixotropic and anti-thixotropic phenomena of non-Newtonian flow. This study investigates the behaviors of cellulose suspensions and SMS pastes under constant shear rate. The results imply that the presented model with only two parameters is adequate to fit experimental data. Moreover, the parameter of fractional order is an appropriate index to characterize the state of given substances. Its value indicates the extent of thixotropy and anti-thixotropy with positive and negative order respectively.

**KEYWORDS**

PAPER SUBMITTED: 2016-04-26

PAPER REVISED: 2016-05-24

PAPER ACCEPTED: 2016-06-15

PUBLISHED ONLINE: 2016-10-01

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**1**, PAGES [61 - 68]

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