HI every body

I'm trying to simulate an open cycle of an CI engine with the AVL Fire software . I have done my mesh and now I'm trying to do the calculations and my solution diverges . i wanna know if any of you guys have done the same thing or similar to that Cuz I wanna know how to do the initialization to make the solution more stable (i mean the initial turbulent kinetic energy and dissipation rate ) and some other setting that might affect the convergence .

Thanks a lot

hi well I must know more on your problem, but there seems you have used the default values for the turbulent kinetic energy and dissipation rate. in case of ICE, these values should be accurately determined. As the in cylinder Fluid mechanical Phenomena is quite complex, the initial guess becomes more critical. In order to get a more stable solution, one of important things is to set proper initial conditions, far different from the software default values, i.e. in ICE cases, usually the turbulent kinetic energy is of order 10, and the default value is just 0.001!

[valikiut]

Hi everyone,
I am new user of AVL Fire and I want to simulate simple diesel engine combustion. In solver steering file (SSF), I use eddy breakup combustion model for combustion and diesel model for auto ignition model and their default constant for them, but I have some problems. The start of combustion is late and the results are unacceptable. How can I modify it? Should I change auto ignition model or its constants? What is the best model for combustion and auto ignition model for diesel? How can I change injection pressure? There is nothing in SSF file for injection pressure. Would I have your SSF file for diesel combustion?
Please help me.
Thanks.