Fluid Mechanics Flashcards
What is the effect of shear stress on dialant fluids?
Shear Thickening. As the rate of shear stress increases so does the coefficient of viscosity.
Give an example of a dialant fluid
Sugar in water
If a fluid undergoes shear thickening when subjected to shear stress, what type of fluid is it?
Dialant Fluid
What is the effect of shear stress on pseudo-plastic fluids?
Shear thinning. As the rate of shear increases the coefficient of viscosity decreases.
Give an example of a pseudo-plastic fluid
Milk, blood, gelatine
If a fluid undergoes shear thickening when subjected to shear stress, what type of fluid is it?
pseudo-plastic fluid
what is known about the density of an incompressible fluid?
density is constant
what is the dynamic viscosity of an ideal fluid?
Zero
Define viscosity
Viscosity is a measure of a fluids reluctance to shear.
resistance to the movement of one fluid layer over an adjoining layer
Define kinematic viscosity
dynamic viscosity / density
What is specific weight?
density multiplied by gravitational acceleration
give an equation to find specific volume
1/density
What is the difference between Newtonian and Non-Newtonian fluids?
In a newtonian fluid viscosity is independent of the rate of shear - but may change with temperature.
In an non-newtonian fluid viscosity varies with rate of shear
The viscosity of a fluid changes when the rate of shear applied to it changes. What type of fluid is this?
non-newtonian fluid
What is pascals law (for pressure)?
Pressure
