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Hi,

I did an analysis with a sensitivity study: I ran the same analysis four times with different velocity diffusivities (1 and 0.5) and different laws of friction (Strickler's and Chezy).

I analyzed a fjard with the tide coming in and going out over a twelve-hour time period.

I have a question: what is the real difference between Strickler's and Chezy? When would you use one or the other?

I have attached the run files and a PDF with the results (flow velocity versus time). As you can see, they're pretty similar, except for the 1 m-s VD Chezy, which has a huge spike at around the fifth hour. It looks like sloshing when I view the animation.
Also, generally the analyses with the Chezy law of friction have slightly faster flow velocities.

Thanks,
ME

OK, my input files didn't upload. Trying again.

Any help?

Hello,

Jean-Michel Hervouet answered you on that question months ago.
"The Chézy's law is like the Strickler law, but without the dependency on depth in the formula, so friction is only proportional to 1/C**2. Anyway the Strickler law is better, because the Strickler coefficient is supposed to depend only on the bed roughness, unlike the Chézy coefficient which in principle is valid only for a given depth, reason why it is seldom used, except perhaps in maritime applications where the depth does not vary much."

Regard, Julien.