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Pressure to Flow Calculator

Flow Rate Formula:

\[ Q = \frac{\pi \times r^4 \times \Delta P}{8 \times \mu \times L} \]

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1. What is a Pressure to Flow Calculator?

Definition: This calculator estimates the volumetric flow rate through a pipe based on pressure difference, pipe dimensions, and fluid viscosity.

Purpose: It helps engineers and technicians determine fluid flow rates in piping systems using the Hagen-Poiseuille equation.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = \frac{\pi \times r^4 \times \Delta P}{8 \times \mu \times L} \]

Where:

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

3. Importance of Flow Rate Calculation

Details: Accurate flow rate estimation is crucial for designing piping systems, ensuring proper fluid delivery, and calculating pump requirements.

4. Using the Calculator

Tips: Enter pipe radius in meters, pressure difference in Pascals, fluid viscosity in Pa·s (default 0.001 for water), and pipe length in meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the Hagen-Poiseuille equation?
A: It describes laminar flow through a cylindrical pipe, valid for Newtonian fluids with constant viscosity.

Q2: What's a typical viscosity value for water?
A: Water at 20°C has a viscosity of about 0.001 Pa·s, which is the default value in this calculator.

Q3: Does this work for turbulent flow?
A: No, this equation is only valid for laminar flow (Re < 2100 typically). Different equations are needed for turbulent flow.

Q4: Why does radius have such a large effect?
A: Flow rate depends on r⁴, so doubling the radius increases flow by 16 times. This is because both area and velocity profile are affected.

Q5: What units should I use?
A: Use consistent SI units: meters for dimensions, Pascals for pressure, and Pa·s for viscosity to get m³/s flow rate.

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