In scaling fluid machinaries, like pump or wind turbine, the classic rule is following the similarity of velocity triangle. You can find this in almost every book about fluid machinary. There are 4 non-dimensional numbers in the non-dimensional N-S equations, and Re is one of them. Which number is applicable in a certain case depends on what we care about. Re is the ratio of inertial and viscous forces. When we want to know about the friction loss, flow pattern which are induced by viscosity, Re should be considered. In fluid machinaries, the ability of transfering shaft power to fluid energy or vise versa is important.  In this situation, Euler number should be considered, which is defined as stream pressure versus inertia forces. Usually, the flux of fluid is regarded constant in fluid machinaries, so Eu can be used as an indicator of pressure energy change across the blade.

I suggest you go through the derivation of dimensionless N-s equation, after which you would find that Eu and similarity of velocity triangle are different forms of the same criteria.

Wish you the best!

Dear Karthik,

I think you could divide you work into two steps:

1. Validation of numerical model.

2. Design of full scale turbine.

So, you can firstly validate your numerical model (includes solver setting, meshing procedure, turbulence model, and etc.) in contrast with the wind tunnel measurements for very tiny turbine that could be fit in your wind tunnel. it will be wise to make the tiny turbine geometrically and kinematically similar to your intended full scale model.

After achieving some agreement with the experimental results, you can design your full scale model with the same numerical model  (includes solver setting, meshing procedure, turbulence model, and etc.).

But, the only problem will be that the small turbine may encounter a laminar flow regime and may be laminar to turbulent transition. This low Re regime may be not expected in the full scale design. Some people could use some techniques to have fast transition in the wind tunnel experiments.

Kind regards,

Mohamed

Dear Karthik,

you should be aware that there are addionally the (blade tip) Mach number (compressibility) and Strouhal number (similar to the velocity triangle) to be matched. You see this cannot be achieved at the same time in a down scaled model without changing the fluid. You may have a look for a water tunnel if you want to achieve high Reynolds number at approximately incompressible flow conditions (air flow would never be totally incompressible as water flow)

By the way, it is not impossible to achieve 260m/s in a wind tunnel - it depends on the tunnel available.