Generalized Newtonian fluid
A generalized Newtonian fluid is an idealized fluid for which the shear stress is a function of shear rate at the particular time, but not dependent upon the history of deformation. Although this type of fluid is non-Newtonian (i.e. non-linear) in nature, its constitutive equation is a generalised form of the Newtonian fluid. Generalised Newtonian fluids satisfy the following rheological equation:
where is the shear stress, and is the shear rate. The quantity represents an apparent viscosity or effective viscosity as a function of the shear rate.
The most commonly used types of generalized Newtonian fluids are:[1]
It has been shown that lubrication theory may be applied to all generalized Newtonian fluids in both two and three dimensions.[2][3]
See also
References
- ^ Kennedy, Peter (1995). Flow analysis of injection molds. Munich u.a.: Hanser u.a. ISBN 1-56990-181-3.
- ^ Pritchard, David; Duffy, Brian; Wilson, Stephen (2015). "Shallow flows of generalised Newtonian fluids on an inclined plane" (PDF). Journal of Engineering Mathematics. 94 (1): 115–133. Bibcode:2015JEnMa..94..115P. doi:10.1007/s10665-014-9725-2. S2CID 254473611.
- ^ Hinton, Edward (2022). "Inferring rheology from free-surface observations". Journal of Fluid Mechanics. 937. arXiv:2202.02893. Bibcode:2022JFM...937R...4H. doi:10.1017/jfm.2022.157. S2CID 246634281.