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Flow Through Orifice Calculation

Flow Rate Formula:

\[ Q = C_d \times A \times \sqrt{\frac{2 \times \Delta P}{\rho}} \times 448.83 \]

dimensionless
ft²
psi
lb/ft³
GPM

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1. What is Flow Through Orifice Calculation?

Definition: This calculator determines the volumetric flow rate of a fluid through an orifice based on the orifice characteristics and fluid properties.

Purpose: It helps engineers and technicians design and analyze fluid systems with orifices, which are common in piping, hydraulic, and pneumatic systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = C_d \times A \times \sqrt{\frac{2 \times \Delta P}{\rho}} \times 448.83 \]

Where:

Explanation: The formula calculates the theoretical flow rate through an orifice, accounting for the discharge coefficient which represents the efficiency of the orifice.

3. Importance of Orifice Flow Calculation

Details: Accurate flow rate calculations are essential for system design, performance analysis, and troubleshooting in various engineering applications.

4. Using the Calculator

Tips: Enter the discharge coefficient (default 0.62 for sharp-edged orifices), orifice area, pressure difference, and fluid density (default 62.4 lb/ft³ for water). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the discharge coefficient (Cd)?
A: It's a dimensionless factor that accounts for flow losses through the orifice. Typical values range from 0.6 to 0.9 depending on orifice geometry.

Q2: How do I calculate orifice area?
A: For circular orifices: \( A = \pi \times (d/2)^2 \) where d is diameter in feet.

Q3: What's the 448.83 factor in the formula?
A: This converts the result from ft³/s to gallons per minute (GPM).

Q4: When would I change the fluid density?
A: When working with fluids other than water (e.g., oil = ~55 lb/ft³, gasoline = ~42 lb/ft³).

Q5: Does this work for compressible fluids?
A: This formula is for incompressible fluids. For gases, additional factors like compressibility must be considered.

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