Pressure and Volumetric Flow Rate Calculator

Flow Velocity and Volumetric Flow Rate 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

Fluid Density (ρ):

lb/ft³

Cross-sectional Area (A):

ft²

Flow Velocity (V): ft/s

Volumetric Flow Rate (Q): GPM

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1. What is a Pressure and Volumetric Flow Rate Calculator?

Definition: This calculator determines the flow velocity and volumetric flow rate based on pressure difference, fluid density, and cross-sectional area.

Purpose: It helps engineers and technicians analyze fluid flow systems and design piping networks.

2. How Does the Calculator Work?

The calculator uses these formulas:

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

Where:

\( V \) — Flow velocity (ft/s)
\( P_1 \) — Initial pressure (psi)
\( P_2 \) — Final pressure (psi)
\( \rho \) — Fluid density (lb/ft³)
\( Q \) — Volumetric flow rate (GPM)
\( A \) — Cross-sectional area (ft²)

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

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculations are essential for proper system design, pump selection, and ensuring adequate fluid delivery.

4. Using the Calculator

Tips: Enter pressure values (psi), fluid density (default 62.4 lb/ft³ for water), and cross-sectional area (ft²). All values must be > 0 except P₂ which can be 0.

5. Frequently Asked Questions (FAQ)

Q1: What does the 144 factor represent?
A: It converts psi (lb/in²) to lb/ft² (1 ft² = 144 in²).

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

Q3: What density should I use for other fluids?
A: Use 49.1 lb/ft³ for gasoline, 78.6 lb/ft³ for seawater, or look up specific values for your fluid.

Q4: How do I calculate pipe cross-sectional 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 ideal flow. For real systems, consider additional factors like pipe roughness and length.