Nusselt Number Calculator
A Nusselt Number Calculator is a tool used to determine the Nusselt number (Nu), which represents the ratio of convective to conductive heat transfer in a fluid system.
Why Use a Nusselt Number Calculator?
- Helps in heat transfer analysis for fluids in pipes, over surfaces, or in cooling/heating systems.
- Used in engineering to design efficient heat exchangers, cooling systems, and insulation materials.
- Essential in fields like thermodynamics, fluid mechanics, and HVAC.
How Does It Work?
The Nusselt number (Nu) is calculated as:

where:
- h = convective heat transfer coefficient (W/m²·K)
- L = characteristic length (m)
- k = thermal conductivity of the fluid (W/m·K)
It can be computed using empirical correlations depending on flow type (laminar or turbulent) and geometry.
When to Use It?
- In heat exchanger design for industry, automotive, and aerospace.
- In cooling systems, like CPU cooling or nuclear reactor design.
- For predicting heat transfer efficiency in natural or forced convection.