Hose Flow Rate Calculator

Hose Flow Rate Calculator:

Enter the values of diameter, D_(in),  pressure, P_(psi) and length, L_(ft) to determine the value of Flow rate, Q_(gpm).

Enter Diameter:		in
Enter Pressure:		psi
Enter Length:		ft
Result – Flow Rate:		gpm

Hose Flow Rate Formula:

Hose flow rate refers to the amount of fluid that passes through a hose over a specific period. It is an important factor in fluid dynamics and is widely used in industries such as agriculture, firefighting, and plumbing. The flow rate is affected by the pressure drop, the hose diameter, and the length of the hose. In many cases, a larger diameter hose allows for a higher flow rate, while a longer hose or one with rough surfaces will reduce the flow. The relationship between these factors can be mathematically modeled to estimate the flow rate, which is typically expressed in gallons per minute (GPM) or litres per second (L/s).

The flow rate depends on the pressure, diameter of the hose, and its length. As the diameter increases, the flow rate increases, but as the length of the hose increases, the flow rate decreases due to frictional losses. In addition, the pressure of the fluid being pushed through the hose plays a significant role in determining how much fluid can flow. The more pressure applied, the higher the flow rate.

The formula for calculating the flow rate incorporates the diameter (D), pressure (P), and length (L) of the hose. The pressure drop across the length of the hose is a critical factor, as it dictates the velocity and volume of the fluid that passes through the hose. The power-law formula provided can estimate the flow rate of fluids through hoses in many practical situations.

Flow rate, Q_(gpm) in gallons per minute is equal to the constant 1946.6 multiplied by the diameter, D_(in) in inches raised to the power of 1.857, then multiplied by the pressure, P_(psi) in pounds per square inches divided by the length, L_(ft) in feet and this result is raised to the power of 0.54.

Flow rate, Q_(gpm) = 1946.6 * D^1.857_(in) *  (P_(psi) / L_(ft))^0.54

Q_(gpm) = flow rate in gallons per minute, gpm.

D_(in) = diameter in inches, in.

P_(psi) = pressure in pounds per square inch, psi.

L_(ft) = length in feet, ft.

Hose Flow Rate Calculation:

1. Given: D_(in) = 4in, P_(psi) = 100psi, L_(ft) = 20ft.

Flow rate, Q_(gpm) = 1946.6 * D^1.857_(in) *  (P_(psi) / L_(ft))^0.54

Q_(gpm) = 1946.6 * 4^1.857_(in) *  (100 / 20)^0.54

Q_(gpm) = (1946.6 * 12.832 * 5)^0.54

Q_(gpm) = (1946.6 * 64.16)^0.54

Q_(gpm) = (124892.976)^0.54

Q_(gpm) = 60918 gpm.

2. Given: D_(in) = 3in, P_(psi) = 120psi, Q_(gpm) = 500gpm.

Flow rate, Q_(gpm) = 1946.6 * D^1.857_(in) * P_(psi) / L_(ft))^0.54

L_(ft) = 1946.6 * D^1.857_(in) * P_(psi) / Q^1/0.54_(gpm)

L_(ft) = 1946.6 * 3^1.857 * 120 / 500^1/0.54

L_(ft) = 1946.6 * 7.564 * 120​ / 163.22

L_(ft) = 1765977.33​ / 163.22

L_(ft) = 10819.98 ft.