Dear Waleed,

I think that normally Reynol number is calculated due to the same method for any solutions. Herein, you can do as follows

Reynolds Number for a Pipe or Duct: Re = ρ u dh / μ  = u dh / ν     .

where, dh = hydraulic diameter (m, ft), Re = Reynolds Number (non-dimensional)

ρ = density (kg/m3, lbm/ft3  ), u = velocity based on the actual cross section area of the duct or pipe (m/s, ft/s), μ = dynamic viscosity (Ns/m2, lbm/s ft)

ν = μ / ρ =  kinematic viscosity (m2/s, ft2/s)

For more details:

http://www.engineeringtoolbox.com/reynolds-number-d_237.html

Good luck,

Dang

Thanks, but I have two liquids with different properties and different from.

Oil in liquid form and methanol in supercritical form

If you want to design 2 pipes separately, 1 for oil and 1 for methanol, I think it is not difficult. This method is ok if you can determine full of parameters in Reynold equation for both oil and methanol.

However, if you want to design 1 pipe for mixture of oil and methanol, you need to know the average values of them

 Dear Dang, the two liquids are in one pipe but  not mixed or immiscible, you can say that it is a slug flow, so I don't think that the average will be the suitable method

The Reynold's number (Re) is defined by the fluid flow velocity (v), density (rho) and the pipe diameter (D) and divided by the dynamics viscosity (mu).

Since you have a heterogeneous flow, then you need to calculate an average density and an average viscosity based on the proportion of each fluid in the mixture.

Hope this helps answer your question.

Professor Yehia Khalil

Yale University

USA

Thanks Prof. Yehia

Thanks dear Premchand

Since you have a heterogeneous flow, then you need to calculate an average density and an average viscosity based on the proportion of each fluid in the mixture.

Hi friends,I had the same problem of Waleed Shaaban but in my case I use propane-Air mixture...Can any one help to calculate reynolds number of this mixture plz?

thank you