Hydraulics Flashcards
How much head pressure is there in a 1ft column of water
.434 psi
Determine the volume of a square (in Gallons)
Length x Depth x Width x 7.5
Theoretic flow for 1/2” tip at 50 psi
53 GPM
Theoretic Flow for 7/8” tip at 50 psi
161 GPM
Theoretic Flow for 1” tip at 50 psi
210 GPM
Fire Ground Flows for hand line tips and nozzles @ 50psi
1/2” = 50 GPM
7/8” = 150 GPM
15/16” = 185 GPM
1” = 210 GPM
1 1/8” = 250
1 1/4” = 325
Theoretic Flow of 15/16” tip at 50 PSI
185 GPM
Theoretic flow for 1 1/8” tip at 50 psi
266 GPM
Theoretic flow for 1 1/4” tip at 50 psi
328 GPM
Theoretic flow of 1 1/4” tip at 80 psi
415 GPM
Theoretic flow of 1 3/8” tip at 80 psi
502 GPM
Theoretic flow of 1 1/2” tip at 80 psi
598 GPM
Theoretic flow of 1 3/4” tip at 80 psi
814 GPM
Theoretic flow of 2” tip at 80 psi
1062 GPM
Fixed monitor Smooth Bore Flow and Starting Pressures (Deck Gun) ALL TIPS
1 3/8” tip : 500 GPM - starting pressure 110 psi
1 1/2” tip: 600 GPM - starting pressure 110 psi
1 3/4” tip: 800 GPM - starting pressure 110 psi
2” tip: 1000 GPM - starting pressure 120 psi
TFT automatic nozzle flows and pressure
@ 90 psi: 500 GPM
@ 110 psi: 750 GPM
@ 120 psi: 1000 GPM
@ 140 psi: 1250 GPM
Akron Adjustable Monitor Flow Nozzle pressures and flows (MASTERSTREAM)
100 psi: 500 GPM
110 psi: 750 GPM
130 psi: 1000 GPM
140 psi: 1250 GPM
Definition of friction loss
Anything that affects the movement of water
1st principle of friction loss
Variables being the same, doubling the length of hose will double friction loss
2nd principle of friction loss
Friction Loss varies approximately with the square of the increase in flow
3rd Principle of Friction Loss
If Flow remains constant Friction Loss will decrease if the diameter is increased
4th Principle of Friction Loss
The velocity of water, NOT PRESSURE, through a hose causes friction loss, the faster you move water (GPM) the more friction loss occurs (psi)
Friction Loss formula COEFFICIENTS
1” = 150
1 3/4” = 10 (NFPA 15)
2” = 8
2.5” = 2
3” = .8
4” = .2
5” = .08
Appliance Loss
When Flows are over 350 GPM
Any appliance : 10 psi
Ladder Pipes : 25 psi
Stand Pipes: 25 psi
Mercury Monitor : 10 psi
√50
7.07
√80
8.94
Stream Velocity Formula
12.14 x √NP = ft/s
1.75 squared ( Q of 175 GPM)
3.06
1.85 squared (Q of 185 GPM)
3.42
2.96 squared (Q of 296 gpm)
8.76
Friction Loss Formula
C = coefficient based on hose diameter
Q = Flow Rate (squared) in hundreds
L= Hose Length in hundreds
JS-10 Flow Patterns
Spray or Straight Stream
Portable Foam Eductor
Flow:
Intake Pressure:
Distance from Panel:
Nozzle Height
Flows 95 to 125 gpm
Must be pumped @ 200 psi at eductor
At least 50’ from pump panel to avoid turbulence and within 200’ of nozzle
Nozzle cannot be placed higher than 5 ft over eductor
Supply Hose starting pressures
4” = 50 psi
3” = 100 psi
If combined they should be charged to min 100 psi
Max achievable discharge pressure
150 psi + static Pressure = Max rated pump flow capacity (1500 gpm)
Friction Loss coefficients in multiple supply lines
Two 3” lines = .2
One 3” and one 4” = .09
Two 4” = .05
Like Volumes formula
[(Static Pressure - Residual Pressure) 100] / Static Pressure
Like Volumes alternate method
Calculate 25%, 15% , 10% of static pressure and match the drop between static and residual.
Like Volumes Chart
0 - 10% drop = 3 like volumes
10.1% - 15% drop = 2 like volumes
15.1% - 25% drop = 1 like volume
> 25% drop = Less than 1 original amount
Fog Nozzle flows
1” adjustable = 12 - 60 gpm
1 1/2 Akron assault = 175 gpm
2 1/2 Akron fog = 125 to 250 gpm
Akron Quick-Attack = 500 gpm
Length, Diameter, Flow and Pressure for booster reels
150’ length - 1” thick - 100 psi nozzle - 12 to 60 GPM
Coefficient for friction loss: 150
Decon Shower flow and pressure
270 GPM at 75 psi
Piercing Nozzle
125gpm @ 100 psi