FE Exam Formulas Ch. 8 Flashcards
Purpose and Variables of…
Density Formula
rho=density
m=mass
V=volume
Purpose and Variables of…
Specific Weight Formula
gamma=specific weight
W=weight
V=volume
Purpose and Variables of…
Specific Weight Using Mass
gamma=specific weight
g=gravity
m=mass
V=volume
Purpose and Variables of…
Specific Gravity Formula
SG=specific gravity
g=gravity (32.3 ft/s^2)
gamma=specific weight
gammaw=specific weight of water (62.43 lbf/ft^3)
Purpose and Variables of…
Density of Homogeneous Fluids
rho=density
m=mass
V=volume
Purpose and Variables of…
Specific Weight of Homogeneous Fluids
gamma=specific weight
W=weight
V=volume
Purpose of…
Fahrenheit to Celsius
Purpose and Variables of…
Fahrenheit to Rankine
Purpose and Variables of…
Kelvin to Celsius
Purpose and Variables of…
tau=shear stress
Purpose and Variables of…
Normal Stress Component
taun=normal stress
P=pressure
Purpose and Variables of…
Tangential Stress Component
taut=tangential stress
mu=absolute dynamic viscosity
Purpose and Variables of…
Kinematic Viscosity Formula
upsilon=kinematic viscosity
mu=absolute dynamic viscosity
rho=density
Purpose and Variables of…
Linear Velocity Profile
v=velocity
delta=cylinder clearance
Purpose of…
Shear Rate
Purpose and Variables of…
Pressure Equation Between Two Elevations
Pn=pressure at elevation
gamma=specific weight
zn=elevation
rho=density
g=gravity (32.2)
Purpose and Variables of…
Nonlinear Model for Fluids
taut=tangential stress
K=flow consistency index
n=power law index
Purpose and Variables of…
Surface Tension
sigma=surface tension
F=surface force at interface
L=length of interface
Purpose and Variables of…
Capillarity
h=height of liquid in vertical tube
sigma=surface tension
beta=angle made by liquid with tube wall
gamma=specific weight of liquid
d=diameter of tube
Purpose of…
Manometer Pressure
Purpose of…
Barometer Pressure
Purpose and Variables of…
Atmospheric Pressure Head
h=head
p=pressure
rho=density
g=gravity (32.2)
gamma=specific density
Purpose and Variables of…
Force at a Distance
FR=force at a distance
Patm=atmospheric pressure
rho=density
g=gravity
yc=distance
theta=aligned surface angle
Purpose and Variables of…
Depth of Resultant Force Location
ycp=depth of resultant force
yc=distance
Ixc=area moment of inertia of the submerged surface
Purpose of…
Resultant Force on a Vertical Plane Surface
Purpose and Variables of…
Depth of the Center of Pressure
ycp=depth of resultant force
yc=distance
Ixc=area moment of inertia of the submerged surface
Purpose and Variables of…
Pressure on a General Vertical Plane Surface
phat=pressure
rho=density
g=gravity (32.2)
hc=height from centroid
Purpose and Variables of…
Location of the Center of Pressure of Plane Surface
hcp=location of center of pressure
hc=height from center
Ic=moment of inertia at centroid
A=surface area
Purpose and Variables of…
Buoyant Force
rho=density
g=gravity (32.2)
Vdisplaced=displaced fluid volume within submerged body
Purpose and Variables of…
Mass Flow Rate (One Dimensional Flow)
m=mass flow rate
rho=density
Q=volumetric flow rate
Purpose and Variables of…
Volumetric Flow Rate (One Dimensional Flow)
Q=volumetric flow rate
v=average flow velocity
A=area
Purpose and Variables of…
Continuity Equation (One Dimensional Flow)
v=average flow velocity
A=area
Purpose and Variables of…
Bernoulli’s Equation
P=pressure
gamma=specific density
v=flow velocity
g=gravity (32.2)
z=elevation
Purpose of…
Elevation of Hydraulic Gradient
Purpose of…
Elevation of Energy Grade Line
Purpose and Variables of…
Energy Equation
Purpose and Variables of…
Darcy-Weisbach Equation
f=Darcy friction factor
D=diameter of pipe
L=length over which the pressure drop occurs
epsilon=roughness factor for pipe
(epsilon/D)=relative roughness
Purpose and Variables of…
Reynolds Number
rho=mass density
D=diameter of pipe
mu=dynamic viscosity
upsilon=kinematic viscosity
Purpose and Variables of…
Laminar Flow Equation
r=distance from centerline
R=distance between plates or radius of tube
v(r)=local velocity at r
vmax=velocity at centerline of a duct
vhat=average velocity
Purpose of…
Maximum Velocity in Circular Tubes in Laminar Flow
Purpose of…
Maximum Velocity in Parallel Plates in Laminar Flow
Purpose of…
Maximum Velocity in Fully Turbulent Flow
Purpose and Variables of…
Hagen-Poiseuille Equation
r=radius of pipe
Pf=pressure drop due to friction
D=diameter of pipe
L=length of pipe
8muL/pir^4=flow resistance
Purpose and Variables of…
Head Loss due to Pipe Fitting
P=pressure
gamma=specific density
v=flow velocity
g=gravity (32.2)
z=elevation
hf=head loss due to friction
hffitting=head loss due to fitting
Purpose and Variables of…
Fluid Shear Stress Distribution
tau=shear stress at r
tauW=shear stress at R (wall)
Purpose and Variables of…
Fluid Power Equation
Wfluid=power of fluid
H=head increase
Q=volumetric flow rate
hp=head added by pump
rho=density
Purpose and Variables of…
Pump (Brake) Power Equation
W=power
H=head increase
Q=volumetric flow rate
rho=density
etapump=efficiency of pump
Purpose and Variables of…
Purchased Power Equation
Wpurchased=purchased power
W=power
etamotor=efficiency of motor
Purpose and Variables of…
Pump Power Equation
W=power
Q=volumetric flow rate
gamma=specific density
h=head the fluid has to be lifted
etat=total efficiency
Purpose and Variables of…
Net Positive Suction Head Available
NPSHA=net positive suction head available
Hpa=atmospheric pressure head on the surface of the liquid in the pump
Hs=static suction head of liquid, height of the surface of the liquid above the pump
SigmahL=total friction losses in suction line
Hvp=vapor pressure head of liquid at operating temperature
pinlet=inlet pressure to pump
vinlet=velocity at inlet to pump
Pvapor=fluid vapor pressure of fluid being pumped
Purpose and Variables of…
Net Positive Suction Head Available
NPSHA=net positive suction head available
Hpa=atmospheric pressure head on the surface of the liquid in the pump
Hs=static suction head of liquid, height of the surface of the liquid above the pump
SigmahL=total friction losses in suction line
Hvp=vapor pressure head of liquid at operating temperature
pinlet=inlet pressure to pump
vinlet=velocity at inlet to pump
Pvapor=fluid vapor pressure of fluid being pumped
Purpose and Variables of…
Impulse-Momentum Principle
SigmaQ1rho1v1=the rate of momentum of the fluid flow entering the control volume in the same direction of the force
SigmaQ2rho2v2=the rate of momentum of the fluid flow leaving the control volume in the same direction of the force
Purpose and Variables of…
Power Law Reynolds Number
K=flow consistency index
n=power law index
Purpose and Variables of…
Stagnation Pressure for an Incompressible Fluid
v=velocity of the fluid
P0=stagnation pressure
Ps=static pressure of the fluid at the elevation where the measurement is taken
Purpose and Variables of…
Orifice Flow Discharge
C=coeffiecient of discharge
v2=veolicty of fluid exiting the orifice
Purpose and Variables of…
Orifice Flow Discharge
C=coeffiecient of discharge
v2=veolicty of fluid exiting the orifice
Purpose and Variables of…
Orifice Flow Discharge
C=coeffiecient of discharge
v2=veolicty of fluid exiting the orifice
Purpose of…
Venturi Meters
