# Reynolds number calculation verification

Hi guys,

I just wanted to verify my calculation of a reynolds number of a wind turbine. I understand that the reynolds number will vary in a spanwise direction along the blade due to changes in the characteristic length(chord width) and velocity(due to the tip speed ratio). As a way to approximate the reynolds number I've taken an average chord length.

v = 5 (free stream velocity)
lamda = 6 (tip speed ratio)
v* = kinematic visocity of air at 10degrees = 1.4207E-5
l = 0.5 (average chord length)

Now this is the part im unsure of. Do I find an average velocity as follows for the calculation:

Vavg = (v*lamda)/2 (Average velocity)

and then calculate as follows:

(Vavg*l)/v*

Last edited:

## Answers and Replies

SteamKing
Staff Emeritus
Science Advisor
Homework Helper
Units anyone?

What is a tip speed ratio? How is it defined?