1. What is Poiseuille's Law?

Poiseuille's Law describes the flow of a viscous fluid through a cylindrical pipe. It calculates the volumetric flow rate based on pressure difference, pipe dimensions, and fluid viscosity.

2. How Does the Calculator Work?

The calculator uses Poiseuille's Law:

Where:

• \( Q \) — Flow rate (ml/min)
• \( \Delta P \) — Pressure difference (Pa)
• \( r \) — Radius of the pipe (m)
• \( \mu \) — Dynamic viscosity (Pa·s)
• \( L \) — Length of the pipe (m)
• 60000 — Conversion factor to ml/min

Explanation: The equation calculates flow rate based on the pressure gradient and fluid resistance in a cylindrical pipe.

3. Importance of Flow Rate Calculation

Details: Flow rate calculation is essential in various engineering applications, including plumbing, medical devices, chemical processing, and hydraulic systems.

4. Using the Calculator

Tips: Enter pressure difference in Pa, radius in meters, viscosity in Pa·s, and length in meters. All values must be positive and non-zero.

5. Frequently Asked Questions (FAQ)

Q1: What units should I use for the inputs?
A: Pressure in Pascals (Pa), radius in meters (m), viscosity in Pascal-seconds (Pa·s), and length in meters (m).

Q2: Why multiply by 60000?
A: The factor 60000 converts the flow rate from m³/s to ml/min (1 m³/s = 60,000,000 ml/min, but the equation already accounts for this conversion).

Q3: What is the typical range for viscosity?
A: Water at 20°C has viscosity of ~0.001 Pa·s. Viscosity varies significantly with temperature and fluid type.

Q4: Does this apply to non-Newtonian fluids?
A: No, Poiseuille's Law applies only to Newtonian fluids with constant viscosity.

Q5: What are the limitations of this equation?
A: Assumes laminar flow, constant viscosity, no slip at walls, and long straight pipes with constant circular cross-section.