Flashcards

Chapter 16: Hydrostatics & Hydraulics

Dakota Templeton Safety ASP Inglês 24 flashcards

Flashcards do conjunto (24)

1HydrostaticsFluid statics, is the science of fluids at rest, and is a subfield within fluid mechanics
2Fluid Dynamics(Hydraulics) Science of fluids in motion
3HydraulicsMechanical properties of liquids.
Used for: generation, control, and transmission of power by the use of pressurized liquids
4Water Properties8.34 pounds/gallon
7.48 gallons/ft^3
1 ft^3 of water weighs 62.4lbs
Weight of water (metric) = 9.8 kilonewtons/ft^3
1 foot of water height = 0.434 lbs/in^2
5Pressure Conversion1 N/m^2 (Newton) = 0.000145 psi
1 psi = 6896 N
6Hydrostatic Pressure EquationP = pressure (psi)
F = force or weight (water: 62.4 lbs/ft^3)
a = area (in^2)
7Torricelli's LawTorricelli's Theorem
Relates speed of fluid flowing out of an opening to the height of fluid above the opening
8Torricelli's Law Equationv = velocity (ft/sec)
g = acceleration due to gravity (9.8 m/s or 32 ft/s)
h = head (ft)
9Torricelli's Law pressure EquationP = pressure (psi)
h = head (ft)
relates speed of fluid flowing out an opening to the height of fluid above the opening
10Head PressureRelates the energy in an incompressible fluid to the height of an equivalent static column of that fluid
11Head Pressure Equationhp = head pressure (ft)
p = gauge pressure
w = weight of water
12Velocity HeadVelocity of a fluid expressed in terms of the head or static pressure required to produce that velocity.
13Velocity Head Equationhv = velocity expressed in head (ft)
v = velocity (ft/s, m/s, etc.)
g = acceleration of gravity
14Laminar Flow"Streamline flow"
Occurs when a fluid flows in parallel layers, with no disruption between the layers
15Turbulence"Turbulent Flow"
Fluid regime characterized by chaotic, stochastic property changes.
Described in terms of their Reynold's (Re) number.
16Reynold's NumberThis is a dimensionless number that gives a measure of the ratio of inertial forces to viscous forces and consequently quantifies the relative importance of these two types of forces for given flow conditions.
Laminar flow: Re <2,000
Transitional flow: 2,000 < Re < 4,000
Turbulent flow: >4,000
17Velocity Pressurepv = pressure at constant laminar flow (psi)
Q = flow rate (gpm)
d = pipe diameter (inches, ft, m)
18Different Flow Rates EquationQ2 = final flow rate after increasing the flow rate of system 1 (gpm)
Q1 = flow rate under original conditions (gpm)
S = highest pressure in the system (psi)
R1 = pressure that the system dropped to as a result of running at specific conditions (1) (psi)
R2 = pressure that the system dropped to as a result of running at specific conditions (2) (psi)
19Pressure used in a system Equationp = pressure (psi)
Q = flow rate (gpm)
K = discharge coefficient (0-1)
20Flow Rate/Pressure EqQ = flow rate
P = pressure (psi)
21Pressure Loss Due to Friction EquationPd = pressure lost to friction (psi/ft)
Q = flow rate (gpm)
C = coefficient of Roughness of the pipe
d = inside pipe diameter (in)
22Bernoulli's PrincipleFor an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy
23Bernoulli's Principle Equationva = velocity at point A (ft/s, m/s)
vb = velocity at point B (ft/s, m/s)
g = gravity (9.8 m/s or 32.2 ft/s)
pa = pressure at point A (psi)
pb = pressure at point B (psi)
Za = elevation at point A (ft)
Zb = elevation at point B (ft)
w = weight (not mass), (rho x g)
hab = piezometric head (sum of the elevation z and the pressure head between points A and B)
24PressureForce per area of unit