Roughness in Saturne
Posted: Thu May 19, 2011 10:33 am
Dear all,
I am new to Saturne and currently use it for the roughness studies of the wind turbine's blade.
I have a question about the way Saturne simulate the roughness impact in wall-function. More precisely, by chance, I have found a formula in the thesis report[1] concerning code Saturne:
u/u*=1/k*ln((dy+ks)/ks)
,where k,dy, and ks stand for kappa, first grid form wall and roughness respectively.
On the other hand, Ansys Fluent, http://my.fit.edu/itresources/manuals/f ... ode253.htm , declares, in (7-13-x) ,the formula for roughness quite differently to the one above.
So i would be grateful if anyone can verify this formula and its validity in external flow.
Thanks in avance,
Quan.
[1] report here attached in French, page 55.
I am new to Saturne and currently use it for the roughness studies of the wind turbine's blade.
I have a question about the way Saturne simulate the roughness impact in wall-function. More precisely, by chance, I have found a formula in the thesis report[1] concerning code Saturne:
u/u*=1/k*ln((dy+ks)/ks)
,where k,dy, and ks stand for kappa, first grid form wall and roughness respectively.
On the other hand, Ansys Fluent, http://my.fit.edu/itresources/manuals/f ... ode253.htm , declares, in (7-13-x) ,the formula for roughness quite differently to the one above.
So i would be grateful if anyone can verify this formula and its validity in external flow.
Thanks in avance,
Quan.
[1] report here attached in French, page 55.