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Introducing Volupe’s Nusselt number calculator

Estimating convective heat transfer coefficients is a commonly recurring task when running thermal analyses. For many applications, standardized empirical correlations can be used to obtain estimates of these coefficients based on the Nusselt number, but crunching the numbers can sometimes be a tedious task. Hence, as part of our continuous stride to simplify the everyday work for simulation engineers, we are now introducing our very own Nusselt number calculator.

About the calculator

The Nusselt number calculator is introduced as part of Volupe’s CFD Handbook. The foundation for the calculator is the summary of empirical correlations also published in the handbook last year (found here).

To use the calculator, you start off by selecting a correlation that best represents your real application. Once you’ve selected a correlation, you are asked to give input on material data, boundary conditions and so forth. For some correlations there may be additional choices to consider as well, depending on e.g. the flow conditions. This will all be evident as you go.

Some correlations give estimates on local Nusselt number, while others give estimates on the average Nusselt number. Some are also able to give both. The output from the calculator will adapt to the choices that you make. In addition to the Nusselt number you will also get indications on other dimensionless properties, such as Reynolds, Prandtl, Grashof and Rayleigh number.

I hope this addition to our CFD Handbook is interesting news and that you will find the Nusselt number calculator useful. As always you are welcome to send any questions or comments to


Johan Bernander

Johan Bernander, M.Sc.

+46 702 95 18 31

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