Fluid Mechanics Flashcards
equilibrium of liquids and the pressure exerted by liquid at rest.
hydrostatic
two equations in hydrostatic
- for constant density fluids (most liquids)
- barometric equations (for ideal gas)
two applications
- simple manometers
- two fluid u-tube manometer
hydrostatic equilibrium is
fluid statics
three equations for fluid dynamics
- continuity equations
- Overall energy balance equation
- mechanical energy balance (MEB) equation
two types of flow in mechanical energy balance equation
- flow of compressible fluids
- flow of incompressible fluids
3 types of incompressible fluids
subsonic flow
sonic flow
supersonic flow
actual velocity/velocity of sound
mach number
When Mach number is less than 1.0 or V is less than C ( less than the speed of sound), then the flow is called
subsonic
When Mach number equal to 1.0 or V is equal to C, then the flow is called
Sonic Flow
When Mach number is greater than 1.0 or V is greater than C (greater than the speed of sound) , then the flow is called
Supersonic Flow
where hydraulic diameter is applicable in replacement of diameter if flow is turbulent and completely filled
non-circular conduits
if flow is laminar and completely filled use
equivalent diameter
for power consumptions for the transport gases in fans use the mechanical energy balance equation for _________________. Considering that delta p is small and density between the two are similar
incompressible fluids
the power consumption for the transport of gases when blowers are involved use the equation
integral of vdp from p0 to p1
head available at the pump inlet to keep the liquid from cavitating or boiling
Net positive suction head (NPSH)
4 metering of fluids
- pitot tube
- head meters (orifice, venturi, nozzles)
- area meters (rotameters)
- meters for open channel flow
use the continuity equation and the MEB equation to be solved simultaneously
branching
the power loss due to friction in a venturi meter is _____________ an orifice meter
less than
fans and blowers are used to
transport gases
pumps and blowers ____________ the mechanical energy of the fluid
increase
a pump will operate safely if its NPSH is
greater than zero
pump to use in capacity = 5000gal/min and head of 15ft of water
axial flow pump
to use if the air is to be delivered at a rate of 200 cfm and a pressure of 10kpa
blower
in a high pressure piping system where joints are regularly broken for maintenance, __________ joints are used
flanged
the resistance of a layer of fluid to flow over the next layer is measured by
viscosity
when movement of a gas vapor is effected at a low pressure (eg. 0.1 kg/cm^2) the equipment is
blower
the inside surface of the pipe has no effect on the friction factor when the flow is
streamline
the higher the BWG rating of a tube is, the lower is the
strength
At a given flow rate through an orifice meter the differential pressure across the
orifice will increase when
the orifice flow area is decreased
The prime mover of a jet pump is a/an
fluid momentum
The weight rate of flow of a fluid stream per unit of cross section perpendicalar to the direction of flow is the
mean mass velocity of the stream
In a reciprocating pump, the ratio of the quantity of liquid actually pumped to
which corresponds to the piston displacement is called
volumetric efficiency
The schedule number of the pipe is an indicator of the pipe’s
thickness
