What is external flow?
In fluid mechanics, external flow is such a flow that boundary layers develop freely, without constraints imposed by adjacent surfaces. Accordingly, there will always exist a region of the flow outside the boundary layer in which velocity, temperature, and/or concentration gradients are negligible. It can be defined as the flow of a fluid around a body that is completely submerged in it.
An example includes fluid motion over a flat plate (inclined or parallel to the free stream velocity) and flow over curved surfaces such as a sphere, cylinder, airfoil, or turbine blade, air flowing around an airplane and water flowing around the submarines.
How to Calculate Nusselt number for gases?
Nusselt number for gases calculator uses Nusselt Number = 2+(0.25*Reynolds Number+(3*10^-4)*(Reynolds Number^1.6))^0.5 to calculate the Nusselt Number, Nusselt number for gases formula is defined as a dimensionless quantity used to characterize convective heat transfer between a sphere and a fluid, typically air or gas, in various engineering and scientific applications, such as heat exchangers, combustion systems, and atmospheric science. Nusselt Number is denoted by Nu symbol.
How to calculate Nusselt number for gases using this online calculator? To use this online calculator for Nusselt number for gases, enter Reynolds Number (Re) and hit the calculate button. Here is how the Nusselt number for gases calculation can be explained with given input values -> 151.654 = 2+(0.25*50000+(3*10^-4)*(50000^1.6))^0.5.