1. What is Flow Velocity in Pipes?

Flow velocity in pipes is the speed at which fluid moves through a pipe's cross-section. It's a fundamental parameter in fluid dynamics and pipe system design, affecting pressure drop, energy requirements, and flow characteristics.

2. How Does the Calculator Work?

The calculator uses the basic velocity equation:

Where:

• \( Flow \) — Volumetric flow rate (m³/s)
• \( Area \) — Cross-sectional area of the pipe (m²)

Explanation: The equation shows that velocity increases with higher flow rates and decreases with larger pipe diameters (which increase cross-sectional area).

3. Importance of Velocity Calculation

Details: Proper velocity calculation is essential for designing efficient piping systems. Too high velocity can cause erosion and excessive pressure drops, while too low velocity may lead to sedimentation.

4. Using the Calculator

Tips: Enter flow rate in m³/s and cross-sectional area in m². For circular pipes, area can be calculated as π × (diameter/2)². All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical velocity range for water in pipes?
A: For water, typical design velocities are 0.5-2.5 m/s in supply lines and 1.5-3.5 m/s in discharge lines.

Q2: How does pipe diameter affect velocity?
A: For a given flow rate, velocity is inversely proportional to the square of the pipe diameter (halving diameter quadruples velocity).

Q3: What are the units for velocity?
A: Velocity is typically measured in meters per second (m/s) in SI units or feet per second (ft/s) in imperial units.

Q4: Can this calculator be used for gases?
A: Yes, the same equation applies to both liquids and gases, though gas velocities are typically much higher.

Q5: What is the Reynolds number and why is it important?
A: Reynolds number determines flow regime (laminar or turbulent). It depends on velocity, pipe diameter, and fluid properties.