code_saturne User's Forum

Thanks for fast reply. I just need to trim "very long" iterations at initial stage of calculation. Most of iterations, even from very start, are done quickly but some require thousands on linear solver iterations to converge to 1.0E-5 precision (usually for velocity). So I wanted to reduce...

Hello and thanks for suggestion. In your example fields are accessed by name. Can I cycle (loop) through all fields setting maximum ~1000 iterations for every field? Is something like this correct or I must use another approach? for ( iField=0 ; iField<cs_field_n_fields() ; iField++) { cs_field_t* f...

Hello, Ivan. Thanks for useful info! Years has passed from the moment I was here at first time and you still help people to cope with difficulties using Saturne. Great work. I took a look at the cs_user_parameters-linear_solvers.c and, if I get it right, I should change the n_max_iter_coarse_solver ...

Hello. I need to control the maximum number of iterations in linear solver (although I set the precision to 1E-5, sometimes it tries to do too many iterations for velocity). In earlier versions I was able to set the maximum iterations for each variable in GUI, but now, in Saturne 5.0.4, these option...

Hello, rodion . IMHO, you just need to obtain rights for you case directory. When you are in your case directory (check with pwd ), switch to root ( su root ) and then use chmod a+rwx ./* to eliminate access problems for any user. Please be careful while you're under root account. Changing access ri...

Hello. I prepared the case for Code Saturne developers that demonstrate the strange inconsistency in particle flow through the boundary reported by the solver and calculated by integrating the particle mass flux in ParaView (please note that for Fluent both methods give the same value). How to see t...

Hello. Thanks for your response. Formally, the geometry is confidential, but I will make a simple "cube case" to demonstrate the bug (if it's reproducable) when I'll have some time. It will be lighter than the real case. The "abstract cyclone" case for particle flow inconsistency...

Hello. For natural convection cases SST turbulence model is usually used, k-epsilon is definitely not a good choice for this. Your mesh should have a boundary prism layer at the heated surface with Y+ around 1.0 (see, for example, Y+ calculator at cfd-online.com, let the freestream velocity be 1.0 m...

Hello. I think there is a bug in CS 5.0 trunk version. I calculated successfully my cyclone cases and tried to validate another case. The domain has 4 inlets, at each of that the particles-laden gas flow is introduced. The gas phase calculation is OK (isothermal with k-epsilon turbulence model), the...

Yvan Fournier Hello. The trajectory-based method is quite simple. You consider the fluid flow field from the current iteration and define some start points for particles on inlet boundaries. Then you trace particles one-by-one and step-by step. As an abstract simple example, we may use the explicit...