1. What is Water Flow Rate?

Definition: Water flow rate is the volume of water that passes through a given surface per unit time.

Purpose: It's essential for designing water supply systems, irrigation, hydraulic engineering, and plumbing.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (cubic meters per second, m³/s)
• \( A \) — Cross-sectional area (square meters, m²)
• \( v \) — Velocity (meters per second, m/s)

Explanation: The flow rate is calculated by multiplying the cross-sectional area of the pipe/channel by the water velocity.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculations ensure proper system design, adequate water supply, and efficient energy use in pumping systems.

4. Using the Calculator

Tips:

• For circular pipes: Area = π × (radius)²
• Typical velocities: 0.5-3 m/s in pipes (lower for gravity flow, higher for pressurized)
• All values must be > 0

5. Frequently Asked Questions (FAQ)

Q1: How do I calculate area for a circular pipe?
A: Use the formula A = π × r² where r is the radius in meters (diameter/2).

Q2: What's a typical water velocity in household pipes?
A: Typically 1-2.5 m/s for pressurized systems to balance flow and pressure loss.

Q3: Can I use different units?
A: Yes, but convert all units consistently (e.g., cm² to m² by dividing by 10,000).

Q4: How does pipe diameter affect flow rate?
A: Flow rate increases with the square of the diameter (double diameter = 4× flow at same velocity).

Q5: What if I know the flow rate and need to find velocity?
A: Rearrange the formula: v = Q / A.

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