Fourier number calculator

Calculate the Fourier number (Fo) in heat transfer analysis, which represents the ratio of heat conduction rate to heat storage rate

Input Parameters

Calculation Results

Calculation Formula

Fourier Number (Fo) = τα/L²

Where:
Fo = Fourier Number (dimensionless)
τ = Time (s)
α = Thermal Diffusivity (m²/s)
L = Characteristic Length (m)

Result

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Fourier number calculator Calculator Usage Guide

Learn how to use the Fourier number calculator and its working principles in heat transfer analysis

What is the Fourier Number?

The Fourier number (Fo) is a dimensionless number in heat transfer that characterizes how quickly heat diffuses through a material over time. It represents the ratio of the rate of heat conduction to the rate of thermal energy storage.

How to use this calculator

  1. Enter the time (τ) in seconds for which you want to calculate the Fourier number
  2. Enter the thermal diffusivity (α) of the material in m²/s (this can be found in material property tables)
  3. Enter the characteristic length (L) in meters (this depends on the geometry of your system)
  4. Click the "Calculate" button to compute the Fourier number

Practical Applications

The Fourier number is particularly useful in:

  • Transient heat transfer analysis
  • Designing and analyzing cooling systems
  • Material processing where temperature changes over time
  • Predicting how quickly a material will reach thermal equilibrium

Interpretation of Results

A low Fourier number (typically less than 0.2) indicates that the material is changing temperature slowly compared to its thermal properties, while a high Fourier number indicates rapid temperature changes.