Need your help
Dear anyone who can help me. i'm a student in last year, i have a hard subject to do , and if you permit i need your help, that is the problem : I have to study the " Fire induced air flow in a tunnel using the low reynolds k, epsilon model". So i have take the Navier stokes equations ( continuity equation +3 motion equations ( 3 D ) and applied to them the reynolds decomposition ( function = mean of the fuction + fluctuation of the function ) so i have done that for velocities u, v, w and the pressure ; after simplifing i obtain four equations of course , so i must apply the low reynolds number k, epsilon model , and i must close the system equations by another additional equations , so what are these equations , please can you write the system for me , i have already write the first four equations ( continuitu + 3 motion ). Please ,i need your help to begin my work ,i had to dicretize equations and apply a numerical methods ( finite method elements and finite difference method to solve the system. Thank you very much. nb : low reynolds number constants can be found here :http://cfd.me.umist.ac.uk/tmcfd/models/lrnke.html and here : http://cfd.me.umist.ac.uk/tmcfd/models/hrnke.html ps: what i need exactly is the "final system to solve , " JUST THE SYSTEM OF EQUATIONS ", ( i will solve it numerically ) , you can simplify boundary conditions if it's needed or take the simpliest case. Please sir i really need your help , i'm really desperate. Best regards.

Re: Need your help
I am not quite sure about your problem: you have Reynoldsaveraged NS equation which can be closed by applying ke model. So you have: 6 equations (mass, 3 momentums, k and e). The purpose of solving ke equations is to provide turbulent viscosity which is the only additional requirement in the momentum equation. The turbulent viscosity is linked to ke through Mu_t = Fmu *Cmu *density * k^2/e where Fmu is the low Reynolds Number influence.

this is for Mr John. L
Thank you very much for your answer , but i have forget to tell you about a missing equation which contain probably the temperature of the air as a variable, so an additionnal equation > addtionnal variables, what is your opinion sir , can you help me . Best regards.

Re: this is for Mr John. L
Well, you can solve an enthalpy equation (in the form of static enthalpy or total enthalpy) for temperature: the turbulent heat flux overbar(density*v'*h') is linked to Mu_t/Prandtle_Number*grad(h) where h is mean enthalpy  should be able to find it in any turbulence modelling book.

Re: this is for Mr John. L
thank you very much for your answer, i'll follow your advice. Best regards.

Please Mr john.L can you give me you mail
please Mr John. L can you give me your email , i need it in order to send you my work , i need your opinion, we have talked about my work , do you remember ( heated air flow in a ventilated tunnel ) Thank you very much

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