Dear all,
I'm modelling a fire inside a tunnel, based on a 1D simulation. There's something that I don't quite understand: In the 1D simulation, a dimensionless friction coefficient is specified (lambda, value = 0.035). How can I get the same friction coefficient in FDS?
As I understand it from the user guide and technical reference guide, FDS is using a log law for the wall model, based on a sand grain roughness (s). What is the default roughness value in FDS, ans how is it related to the friction coefficient iy 1D simulation? Is it by the moody diagram?
Regards