Chapter 2: Fluid Properties Solid-Liquid-Gas Specific Weight Compressible vs. Non-Compressible Solid under shear vs Liquid under Shear Viscosity Newtonian vs. Non-Newtonian Surface Tension Vapor Pressure

Some properties of fluids Solid – Fluid Solid – liquid – gas –How to best distinguish between them? –Solid properties, and response to container boundaries Mass, density, weight, and the “specifics”

Solid-Liquid and Gas A given mass of liquid will maintain its volume but change its shape to match that of the container where they are in contact.

Dimensions, Units, etc.

Some more fluid properties Solid – Fluid: how does each respond to an applied shear stress? –(How about a applied pressure stress?) Viscosity and rheology What sort of forces does a fluid exert? –Surface tension –Vapor pressure

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What about shear stress?

Top layer of fluid moves with velocity of block Imagine an elastic solid held between two Plates-and then applying a shear force To the top plate Then imagine a long open tank (flume) holding water with a wood block floating on the surface And then apply a shear force to the wood Bottom layer does not move—The NO SLIP condition

Contrast to solid u displacement shear modulus Strain-deformation

Surface Tension

Why 2

Note dependence on R Recall  g is  specific weight

Vapor Pressure

Boiling will occur In Denver the atmospheric pressure is only 95% (see page 40) On Everest only 75%--the boiling points are reduced accordingly