1. What is a Flow Rate in Pipe Calculator?

Definition: This calculator estimates the volumetric flow rate of a fluid through a pipe using the Hagen-Poiseuille equation.

Purpose: It helps engineers and technicians determine fluid flow rates in piping systems for various applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Volumetric flow rate (m³/s)
• \( r \) — Pipe radius (m)
• \( \Delta P \) — Pressure difference (Pa)
• \( \mu \) — Dynamic viscosity (Pa·s)
• \( L \) — Pipe length (m)

Explanation: The flow rate is proportional to the fourth power of the pipe radius and the pressure difference, and inversely proportional to viscosity and pipe length.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculations are essential for designing efficient piping systems, ensuring proper fluid delivery, and avoiding excessive pressure drops.

4. Using the Calculator

Tips: Enter the pipe radius, pressure difference, fluid viscosity (default 0.001002 Pa·s for water at 20°C), and pipe length. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What assumptions does this formula make?
A: It assumes laminar flow, Newtonian fluid, constant viscosity, and no-slip conditions at the pipe walls.

Q2: Can I use this for turbulent flow?
A: No, this equation is only valid for laminar flow (Re < 2100). Different equations are needed for turbulent flow.

Q3: What's a typical viscosity value for water?
A: Water at 20°C has a viscosity of about 0.001002 Pa·s, which is the default value in the calculator.

Q4: Why is radius to the fourth power?
A: The flow rate is extremely sensitive to pipe diameter because of the velocity profile in laminar flow.

Q5: How does pipe length affect flow rate?
A: Longer pipes result in lower flow rates for the same pressure difference due to increased friction losses.