Take a look at the very interesting video above. In particular, I am very much interested in the flow-curve of saliva that is available in this paper.
To me, this flow-curve is quite exceptional.
There are many shear-thinning fluids for which the viscosity decreases with increasing shear rate. For instance, mayo is such a fluid. If mayo is put on a dish and the deformation rate is low, mayo keeps its shape and not that flowing. On the other hand, if mayo is stirred in a bin and the deformation rate is high, it is less viscous than honey, for example. Such a material behavior is so-called shear-thinning.
The flog saliva is a shear thinning fluid. But the shear-thinning property is unusual. The viscosity drastically changes in a narrow range of shear rate. Both sides of this critical shear rate window, the viscosity does not depend on shear rate.
Very interesting. I like this study much, in particular due to the fact that they collected amount of flog’s saliva for the measurements…