fluid-1

# fluid-1 - Basic Fluid Properties and Governing Equations...

This preview shows pages 1–5. Sign up to view the full content.

Basic Fluid Properties and Governing Equations Density ( ρ ): mass per unit volume (kg/m 3 or slug/ft 3 ) Specific Volume (v=1/ ρ ): volume per unit mass Temperature (T): thermodynamic property that measures the molecular activity of an object. It is used to determine whether an object has reached thermal equilibrium. Pressure (p):pressure can be considered as an averaged normal force exerted on a unit surface area by impacting molecules. ( , N/m 2 or pascal; lb/in 2 or psi) Pascal law: (under static condition) pressure acts uniformly in all directions. It also acts perpendicular to the containing surface. If a fluid system is not in motion, then the fluid pressure is equal its thermodynamic pressure. Atomspheric pressure (p atm ): pressure measured at the earth’s surface. 1 atm = 14.696 psi = 1.01325 x 105 N/m 2 (pascal) Absolute pressure: pressure measured without reference to other pressures. Gage pressure: p gage = p absolute - p atm = A F P A 0 lim

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Atmospheric pressure can be measured using a barometer: Vacuum p=0 P atm =1.01x10 5 Pa p=0 p=p atm L constant nal gravitatio the is g fluid, the of density the is balance Force r r r gL P ALg mg W A p atm atm = = = =
Similarly, this balance can be applied to a small fluid element as shown integrate from fluid element to the free surface pA p dp A mg Agdy dp dy g p h p gh - + = = = - = + ( ) , , ( ) r r r p p+dp h Free surface, p=p Example: If a container of fluid is accelerating with an acceleration of a x to the right as shown below, what is the shape of the free surface of the fluid? a x p p+dp pA p dp A ma Adxa dp dx a dy dx dp g dp a a g a g x x x x x x - + = = - = = = = = F H G I K J - ( ) , tan( ) , tan r r a r r a 1 α dx dy x y

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Buoyancy of a submerged body h 1 h 2 p 2 =p + ρ L gh 2 p 1 =p + ρ L gh 1
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 11/27/2011 for the course EML 3002c taught by Professor Staff during the Fall '08 term at FSU.

### Page1 / 15

fluid-1 - Basic Fluid Properties and Governing Equations...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online