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Air Flow Through Orifice Calculator

Air Flow Formula:

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

Pa
kg/m³

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1. What is an Air Flow Through Orifice Calculator?

Definition: This calculator determines the volumetric flow rate of air through an orifice based on the pressure difference across the orifice.

Purpose: It's essential for HVAC system design, pneumatic systems, and any application involving air flow through restricted openings.

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:

Explanation: The flow rate depends on the orifice size, pressure difference, and the discharge coefficient which accounts for flow characteristics.

3. Importance of Orifice Flow Calculation

Details: Accurate flow calculations ensure proper system performance in ventilation, compressed air systems, and fluid control applications.

4. Using the Calculator

Tips: Enter the discharge coefficient (default 0.62 for sharp-edged orifice), orifice area, pressure difference, and air density (default 1.225 kg/m³ at sea level). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical discharge coefficient value?
A: For sharp-edged orifices, C ≈ 0.62. For rounded orifices, it can be higher (0.7-0.9).

Q2: How do I calculate orifice area?
A: For circular orifices, A = π × (diameter/2)². Convert diameter to meters for this calculator.

Q3: What affects air density?
A: Density changes with altitude (pressure) and temperature. Standard air density is 1.225 kg/m³ at 15°C and sea level.

Q4: Can this be used for other gases?
A: Yes, but you must use the correct density for the specific gas.

Q5: What if my pressure difference is very small?
A: For ΔP < 10% of absolute pressure, consider using incompressible flow equations instead.

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