Example:
| Coefficient Table | |
|---|---|
| Diameter | Coefficient |
| 2 inch | 8 |
| 2 ½ inch | 2 |
| 3 inch | 0.677 |
Also question is, how do I calculate flow rate?
Q=Vt Q = V t , where V is the volume and t is the elapsed time. The SI unit for flow rate is m3/s, but a number of other units for Q are in common use. For example, the heart of a resting adult pumps blood at a rate of 5.00 liters per minute (L/min).
Moreover, how do you calculate coefficient of friction loss?
friction loss = friction loss coefficient * ( flow rate / 100) 2 * hose length /100. FL = C* (Q/100)2 *L/100. We have: FL = friction loss.
How do you calculate friction loss in a fire hose?
When you need to calculate friction loss, find your desired gpm and multiply by 12. If you need 125 gpm on 100 feet of hose, that corresponds to number 2 on your finger. Multiply 2 by 12 to get 24; your friction loss is 24 psi.
How do you calculate gpm for a fire hose?
What is the formula for gpm? For example, a one-inch smooth bore tip will have a discharge of 210 gpm: 29.72 × 12 × 7.07 = 210 gpm.
How do you calculate nozzle reaction?
The nozzle reaction is found to be: R = ρ Q 2 / A2 , where A2 is the discharge diameter, Q is the volumetric flow rate, R is the magnitude of the nozzle reaction, and r is the water density. This equation shows that the reaction is proportional to the flow rate squared, divided by the nozzle diameter.
How do you calculate PSI from GPM?
Divide the flow rate measured in GPM by the area and take the square of the result. Multiply the value from step 2 with the density of water and divide by 2. Add the atmospheric pressure to the result from step 3, and you will get the pressure in PSI.
How much psi do you lose per foot of hose?
Hose Pressure Loss (per 100 ft of Hose)
| Hose Friction Pressure Loss (Pressure Drop in PSI per 100FT of Hose with Typical Water Flow Rates) | ||
|---|---|---|
| WATER FLOW GPM | Hose Inside Diameters, Inches | |
| 1 | 54 | 20 |
| 2 | 180 | 60 |
| 3 | 380 | 120 |
What is PSI in fire fighting?
PSI stands for pressure per square inch, and GPM stands for gallons per minute. Both of these are vital in helping you choose what kind of firefighting pump you need, and it is very important to know about the PSI and GPM before buying any pump, regardless of the use.
What is the condensed Q formula?
Take the 1st digit of the flow (gpm) and multiply it by the 1st digit of the next number immediately below it. The result is friction loss per 100′ of 3” hose. … Let’s try a flow of 350 gpm, 3 x 4 equals 12, which is the friction loss in 100 feet of 3” hose. This method is known as Q2 or condensed Q.
What is the friction loss formula?
Consider the equation: FL = c × (gpm/100)2 × L/100. The “c” term is the so-called friction loss factor and measures the pressure loss per 100 feet. This is multiplied by the square of the volume flow (gpm) and hose length (L) to get total friction loss.
What is the friction loss in 5 inch fire hose?
For example, five-inch hose can flow the equivalent of three three-inch hoselines at about the same friction loss. Five-inch LDH can deliver 1,000 gpm at about six psi per 100 feet or 1,500 gpm at 15 psi (friction loss).