Question

Which of the following represents the graph and estimate it with the correct properties?

(a) Dilatant, Decreases with increasing shear rate

(b) Pseudoplastic, Decreases with increasing shear rate

(c) Bingham plastic, Increases with increasing shear rate

(d) Casson plastic, Increases with increasing shear rate

The question was asked in a job interview.

Asked question is from Non Newtonian Fluids topic in division Fluid Flow and Mixing of Bioprocess Engineering

Answer 1

(b) Pseudoplastic, Decreases with increasing shear rate

In pseudoplastic fluids, also known as shear-thinning fluids, the viscosity decreases as the shear rate increases. This behavior is commonly seen in materials like paints and blood, where the fluid becomes "thinner" and flows more easily under increased shear stress. This property is in contrast to dilatant (shear-thickening) fluids, which increase in viscosity as shear rate increases.