[shivakumar]

hi,

From the solution data it is easy to obtain turbulent viscosity at each cell center or node.. In similar fashion, is there any other way to find the laminar viscosity?

Thanks
shivakumar

[CeesH]

The laminar viscosity is an input parameter which you provide under materials.
you can plot it in FLUENT if you want, bu for newtonian fluids it's a constant which you added yourself.

[shivakumar]

can u tell me how to plot it?

[`e`]

The laminar viscosity doesn't appear to be available to plot within Fluent directly. You could save the laminar viscosity of each cell with User-Defined Memory and then plot this UDM (holding the laminar viscosity values). I'm puzzled as to why you'd want to plot a uniform field of values... filling the domain in CFD-Post with a colour would be a quicker method.

[CeesH]

I can see how it might be useful to do make effective viscosity plots for non-newtonian fluids; for newtonian it doesn't make sense indeed.

[shivakumar]

Thanks for the reply

From udf it possible find the laminar viscosity at each....('e')


Yes indeed. for Newtonian flows it does not make sense..For example, when it comes to the viscous sensor algorithm given by Tognaccini, Laminar viscosity does make sense in the region of boundary layer.

D=1+(mu_t/mu_l)

[CeesH]

You could write a simple user defined function that stores the viscosity in a user defined memory. I think this should work:

#include udf.h

DEFINE_ADJUST(my_adjust,d)
 {
    Thread *t;

    cell_t c;

    thread_loop_c(t,d)
    {
     begin_c_loop(c,t)
C_UDMI(c,t,0) = C_MU_L(c,t)
     end_c_loop(c,t)
    }

 }

This stores the laminar viscosity in a user defined memory (don't forget to declare upfront), and user defined memory values can be plotted.

[shivakumar]

Thanks for the reply.. I got it.