##  [Nusselt Number](/nusselt-number) 

  ##  [Nusselt Number](https://engineering.quantumdictionary.io/nusselt-number-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The Nusselt number Nu, a dimensionless group defined as Nu = h·L/k (or analogous), where h is the convective heat‑transfer coefficient, L a characteristic length, and k the thermal conductivity of the fluid; Nu expresses the ratio of convective to conductive heat transfer across a fluid boundary layer.