Water Flow Rate Calculator PSI

Water Flow Formulas:

\[ V = \sqrt{\frac{2 \times (P_1 - P_2) \times 144}{\rho}} \] \[ Q = V \times A \times 448.83 \]

Inlet Pressure (P₁):

psi

Outlet Pressure (P₂):

psi

Water Density (ρ):

lb/ft³

Pipe Area (A):

ft²

Velocity (V): ft/s

Flow Rate (Q): GPM

Definition: This calculator estimates water flow velocity and volumetric flow rate based on pressure difference and pipe cross-sectional area.

Purpose: It helps engineers, plumbers, and irrigation specialists determine water flow characteristics in piping systems.

The calculator uses two formulas:

\[ V = \sqrt{\frac{2 \times (P_1 - P_2) \times 144}{\rho}} \] \[ Q = V \times A \times 448.83 \]

Where:

Explanation: The first equation calculates velocity from pressure difference, then converts to flow rate using pipe area.

Details: Accurate flow rate estimation ensures proper system design, adequate water supply, and efficient operation of hydraulic systems.

Tips: Enter pressure values (psi), water density (default 62.4 lb/ft³), and pipe area (ft²). All values must be positive.

Q1: Why is 144 multiplied in the velocity formula?
A: This converts psi (lb/in²) to lb/ft² (1 ft² = 144 in²) for consistent units.

Q2: What's the 448.83 factor in flow rate?
A: This converts ft³/s to GPM (gallons per minute) - 1 ft³/s = 448.83 GPM.

Q3: When would water density change?
A: Density varies with temperature (62.3 lb/ft³ at 70°F, 62.0 at 100°F) or for other liquids.

Q4: How do I find pipe area?
A: For circular pipes: \( A = \pi \times (D/2)^2 \) where D is diameter in feet.

Q5: Does this account for friction losses?
A: No, this is theoretical maximum flow. Actual flow may be less due to pipe friction.