Water PSI to GPM Calculator

Water Flow Formulas:

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

Initial Pressure (P₁):

psi

Final Pressure (P₂):

psi

Water Density (ρ):

lb/ft³

Pipe Area (A):

ft²

Velocity (V): ft/s

Flow Rate (Q): GPM

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1. What is a Water PSI to GPM Calculator?

Definition: This calculator converts pressure difference (PSI) to flow rate (GPM) using fluid dynamics principles.

Purpose: It helps engineers, plumbers, and irrigation specialists determine water flow rates based on pressure changes and pipe characteristics.

2. How Does the Calculator Work?

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:

\( V \) — Water velocity (feet per second)
\( P_1 \) — Initial pressure (psi)
\( P_2 \) — Final pressure (psi)
\( \rho \) — Water density (pounds per cubic foot)
\( Q \) — Flow rate (gallons per minute)
\( A \) — Pipe cross-sectional area (square feet)

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

3. Importance of PSI to GPM Conversion

Details: Accurate flow rate calculations are essential for designing plumbing systems, irrigation systems, and industrial fluid processes.

4. Using the Calculator

Tips: Enter the pressure difference (P₁ - P₂), water density (default 62.4 lb/ft³ for water), and pipe cross-sectional area. All values must be > 0 except P₂ which can be 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the 144 factor in the formula?
A: It converts psi (lb/in²) to lb/ft² (1 ft² = 144 in²).

Q2: Why 448.83 in the flow rate formula?
A: This converts ft³/s to GPM (1 ft³/s = 448.83 GPM).

Q3: What's typical water density?
A: Pure water at 60°F is 62.4 lb/ft³. Adjust for temperature or additives.

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

Q5: Does this account for friction losses?
A: No, this is theoretical maximum. Real systems will have lower flow due to friction.