Abstract
The measurement and the investigation of the errors in a Couette rheometer have been a topic of considerable interest in many rheometric studies. In the present study, a more accurate predictor-corrector method based on CFD and the analytical solution of the problem is described. Comparing to the previous CFD-based method, in addition to considering the effect of the end parts, the presented correction factors also take into account the effect of the wide gap into a single coefficient. The correction factors are computed for both Newtonian and non-Newtonian fluids in wide and narrow gap rheometry. Results showed that the shear rate distribution across the gap is highly non-linear in non-Newtonian wide gap rheometry. Moreover, for very shear thinning fluid i.e. n < 0.4 in narrow gap rheometry, there is a need to apply correction factor to the calculated fluid properties. Comparing the presented CFD approach and the current approach, the correction factor can be enhanced up to 16% depending on the fluid behavior and the gap distance.
Original language | English |
---|---|
Article number | 35341 |
Journal | Applied Rheology |
Volume | 26 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2016 |
Subject classification (UKÄ)
- Energy Engineering
Free keywords
- CFD
- Correction
- Couette Rheometer
- Fluid properties
- Inverse problem
- Power-law fluid