1. What is the Mass Flow Rate Velocity Equation?

Definition: This equation calculates the mass flow rate of a fluid based on its density, velocity, and cross-sectional area.

Purpose: It's commonly used in fluid dynamics, HVAC systems, and process engineering to determine how much mass of a substance flows through a given area per unit time.

2. How Does the Equation Work?

The equation is:

Where:

• \( W \) — Mass flow rate (lb/hr)
• \( \rho \) — Density of the fluid (lb/ft³)
• \( V \) — Velocity of the fluid (ft/s)
• \( A \) — Cross-sectional area (ft²)
• 3600 — Conversion factor (seconds to hours)

Explanation: The equation multiplies density by velocity and area to get mass per second, then converts to mass per hour.

3. Importance of Mass Flow Rate Calculation

Details: Accurate mass flow rate calculations are essential for system design, process control, and equipment sizing in various engineering applications.

4. Using the Calculator

Tips: Enter the fluid density in lb/ft³, velocity in ft/s, and cross-sectional area in ft². All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 3600?
A: This converts the result from lb/sec to lb/hr (1 hour = 3600 seconds).

Q2: What's a typical density for water?
A: Water at room temperature is about 62.4 lb/ft³.

Q3: How do I find the cross-sectional area?
A: For circular pipes, use \( A = \pi r^2 \) where r is the radius.

Q4: Can I use this for gases?
A: Yes, but be sure to use the correct density for your gas at the operating conditions.

Q5: What if my units are different?
A: Convert all inputs to consistent units (lb/ft³, ft/s, ft²) before calculation.