Home Back

How to Calculate Pressure Loss in Pipe

Darcy-Weisbach Equation:

\[ \Delta P = f \times \frac{L}{D} \times \frac{\rho \times V^2}{2} \]

m
m
kg/m³
m/s
Pa

Unit Converter ▲

Unit Converter ▼

From: To:

1. What is Pressure Loss in Pipes?

Definition: Pressure loss (ΔP) is the reduction in fluid pressure due to friction between the fluid and the pipe walls as the fluid flows through the pipe.

Purpose: Calculating pressure loss helps engineers design piping systems with adequate pump capacity and ensure proper fluid flow rates.

2. How Does the Darcy-Weisbach Equation Work?

The equation calculates pressure loss as:

\[ \Delta P = f \times \frac{L}{D} \times \frac{\rho \times V^2}{2} \]

Where:

Explanation: The equation accounts for friction (f), pipe geometry (L/D), and fluid dynamics (ρV²/2) to determine energy loss.

3. Importance of Pressure Loss Calculation

Details: Accurate pressure loss calculations are critical for:

4. Using the Calculator

Tips:

5. Frequently Asked Questions (FAQ)

Q1: How do I determine the friction factor?
A: For laminar flow (Re < 2000), f = 64/Re. For turbulent flow, use the Moody chart or Colebrook equation.

Q2: Does pipe material affect pressure loss?
A: Yes, through the friction factor - rougher pipes have higher friction factors.

Q3: How does temperature affect the calculation?
A: Temperature affects fluid density and viscosity, which influence the friction factor.

Q4: Can this be used for gases?
A: Yes, but for compressible gases, additional factors must be considered for accurate results.

Q5: What about fittings and valves?
A: These create additional pressure losses typically accounted for using equivalent length or K-factor methods.

Pipe Pressure Loss Calculator© - All Rights Reserved 2025