CHAPTER 1

any substance that deforms continuously so long as shear stress is applied

the measure of the concentration of matter

the volume occupied per unit mass or simply the multiplicative inverse of mass density

a dimensionless ratio of a fluid’s density to some standard reference density

a measure of a fluid’s resistance to shear

the ratio of the absolute viscosity to density

the intensity of molecular attraction per unit length along surfaces or interfaces of contact

Water whose adhesive forces are greater than its cohesive forces

fluid behavior

fractional change in volume of a fluid per unit change in pressure in a constant-temperature process

expresses the compressibility of a fluid

acoustic or sonic velocity of a wave due to pressure disturbances

the equilibrium pressure exerted by the vapor form of a fluid just above the liquid surface

solids at low stresses
viscous liquids at high stresses.

shear thickening (increasing viscosity) in response to increasing applied shear.

shear thinning (decreasing viscosity) due to increasing shear stress.

-increasing viscosity through time

decreasing viscosity through time and tend to solidify when at rest.

viscous (flows when stress is applied) and
elastic (returns to original state when stress is removed)

The pressure gradient, the difference in surface forces acting on the sides of the element, causes a net force that must be balanced by gravity or acceleration.

The pressure distribution ∇P is perpendicular to surfaces of constant pressure.

-vacuum pressure

used to measure atmospheric pressure.

indicates a gage pressure

mechanical gage used to measure atmospheric pressure.

device that converts pressure into an electrical output

Pressure-measuring devices that utilize liquid columns