1. What is the Orifice Flow Equation?

The orifice flow equation calculates the volumetric flow rate of gas through an orifice plate. It's widely used in fluid mechanics and engineering to measure flow rates in pipes and ducts.

2. How Does the Calculator Work?

The calculator uses the orifice flow equation:

Where:

• \( Q \) — Volumetric flow rate (m³/s)
• \( C \) — Discharge coefficient (dimensionless)
• \( A \) — Cross-sectional area of the orifice (m²)
• \( \Delta P \) — Pressure difference across the orifice (Pa)
• \( \rho \) — Density of the gas (kg/m³)

Explanation: The equation relates the flow rate to the square root of the pressure difference, with the discharge coefficient accounting for energy losses.

3. Importance of Orifice Flow Calculation

Details: Accurate flow measurement is essential in many industrial applications including gas pipelines, HVAC systems, and process control in chemical plants.

4. Using the Calculator

Tips:

• Typical discharge coefficient values range from 0.6 to 0.9 (0.61 is common for sharp-edged orifices)
• Standard air density is 1.225 kg/m³ at 15°C and sea level
• Ensure all units are consistent (meters, pascals, kg/m³)

5. Frequently Asked Questions (FAQ)

Q1: What affects the discharge coefficient?
A: The coefficient depends on orifice geometry, edge sharpness, Reynolds number, and the ratio of orifice to pipe diameter.

Q2: Can this be used for liquids?
A: Yes, the same equation applies to incompressible fluids (liquids), though gas calculations may need additional factors for compressibility.

Q3: What's a typical orifice pressure drop?
A: Typically 0.1-0.5 times the upstream pressure, but depends on application requirements.

Q4: How accurate is this calculation?
A: With proper coefficient selection, accuracy can be ±1-2% for calibrated orifices under ideal conditions.

Q5: When is this equation not valid?
A: At very low Reynolds numbers (laminar flow) or when the pressure drop exceeds critical flow conditions.