1. What is the Mass Flow Equation?

The mass flow equation calculates the mass flow rate through a valve or restriction using the flow coefficient (C_v), pressure difference, fluid density, and specific gravity. It's commonly used in fluid dynamics and engineering applications.

2. How Does the Calculator Work?

The calculator uses the mass flow equation:

Where:

• \( m \) — Mass flow rate (kg/s)
• \( C_v \) — Flow coefficient (dimensionless)
• \( \Delta P \) — Pressure difference across the valve (Pa)
• \( \rho \) — Fluid density (kg/m³)
• \( SG \) — Specific gravity relative to water (dimensionless)

Explanation: The equation relates the flow rate to the square root of the pressure difference and density, normalized by the specific gravity.

3. Importance of Mass Flow Calculation

Details: Accurate mass flow calculation is essential for valve sizing, process control, and system design in chemical, petroleum, and mechanical engineering applications.

4. Using the Calculator

Tips: Enter all positive values. C_v is typically provided by valve manufacturers. For water at standard conditions, SG = 1.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for C_v values?
A: C_v values range from less than 1 for small valves to over 1000 for large industrial valves.

Q2: How does temperature affect the calculation?
A: Temperature affects density (ρ) and sometimes specific gravity. Use density values at the operating temperature.

Q3: Can this be used for gases?
A: This form is primarily for liquids. Gas flow calculations require additional factors for compressibility.

Q4: What are common units for C_v?
A: While dimensionless, C_v is often defined as flow in GPM of water at 1 psi pressure drop.

Q5: How accurate is this calculation?
A: Accuracy depends on precise input values and ideal flow conditions. Real-world factors like turbulence may affect actual flow.