Re: Static and Stagnation properties

On 3 Dec 2003 00:32:36 -0800, in sci.mech.fluids
[EMAIL PROTECTED] (Prashanth) wrote:

>What are Static properties? Does he presence of the word "Static" mean
>tha it is the property of the fluid when it is measured at rest? If

While some definitions of static pressure talk about a fluid at rest,
it is more appropriately thought of as the pressure which would be
measured by an instrument that moves along with the fluid. 

>What is the difference between Static Pressure and Stagnation
>Pressure? (As textbooks say that stagnation property is the one when
>the fluid is decellerated to zero velocity at zero datum.- Doesn't
>this mean Staticity or at rest)

Stagnation pressure is the pressure one would have after
isentropically (no losses) decelerating the fluid to a rest.

Think of Bernoulli's eqn,

        p + 0.5*rho*U^2  = const. 

This p is the static pressure. The stagnation pressure is the whole
expression. A common way to measure this pressure is through the use
of wall pressure taps.