Flow Rate Calculator From Pressure

Flow Rate Equation:

\[ Q = C \times A \times \sqrt{\frac{2 \times \Delta P}{\rho}} \]

Discharge Coefficient (C):

unitless

Cross-sectional Area (A):

m²

Pressure Difference (ΔP):

Density (ρ):

kg/m³

Flow Rate (Q):

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1. What is the Flow Rate From Pressure Equation?

The flow rate from pressure equation calculates the volumetric flow rate through an orifice or restriction based on pressure difference, cross-sectional area, fluid density, and discharge coefficient. It's derived from Bernoulli's principle and conservation of energy.

2. How Does the Calculator Work?

The calculator uses the orifice flow equation:

\[ Q = C \times A \times \sqrt{\frac{2 \times \Delta P}{\rho}} \]

Where:

\( Q \) — Volumetric flow rate (m³/s)
\( C \) — Discharge coefficient (unitless)
\( A \) — Cross-sectional area (m²)
\( \Delta P \) — Pressure difference (Pa)
\( \rho \) — Fluid density (kg/m³)

Explanation: The equation calculates flow rate through an orifice based on the pressure drop across the restriction, accounting for energy losses through the discharge coefficient.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculation is essential for designing fluid systems, sizing pipes and valves, process control, and optimizing energy efficiency in various engineering applications.

4. Using the Calculator

Tips: Enter discharge coefficient (typically 0.6-0.8 for sharp-edged orifices), cross-sectional area in m², pressure difference in Pa, and fluid density in kg/m³. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for discharge coefficient C?
A: For sharp-edged orifices, C is typically 0.6-0.8. The exact value depends on the orifice geometry and Reynolds number.

Q2: Can this equation be used for compressible fluids?
A: This simplified form is for incompressible fluids. For compressible fluids (gases), additional factors like expansion factor must be considered.

Q3: What are common applications of this equation?
A: Flow measurement using orifice plates, nozzle design, valve sizing, and various hydraulic and pneumatic system calculations.

Q4: How accurate is this equation?
A: Accuracy depends on proper selection of discharge coefficient and assumptions of steady, incompressible flow without significant viscosity effects.

Q5: What units should be used for accurate results?
A: Use SI units as specified (m², Pa, kg/m³) for consistent results. Convert from other units before calculation.