[rupole1185]

I have this simple case (see attachments).
It represents a car park.

There is an area of this car park where I simulate a simple fire event (I would like to use a source term for the temperature). In this set-up I imposed a 300K fixedValue temperature over the fire boundary.

Well, the simulation seems to be quite unstable and the temperature actually goes down rather than going up ... any idea?

I put some small preview of the settings:

0/T file

boundaryField                                                                   
{                                                                               
    floors                                                                      
    {                                                                           
        type            zeroGradient;                                           
    }                                                                           
    fire                                                                        
    {                                                                           
        type            fixedValue;                                             
        value           uniform 300;                                            
    }                                                                           
    ramps                                                                       
    {                                                                           
        type            fixedValue;                                             
        value           uniform 288;                                            
    }                                                                           
    jetPush                                                                     
    {                                                                           
        type            zeroGradient;                                           
    }                                                                           
    jetSunction                                                                 
    {                                                                           
        type            zeroGradient;                                           
    }                                                                           
    walls                                                                       
    {                                                                           
        type            zeroGradient;                                           
    }                                                                           
}

system/fvSchemes

ddtSchemes                                                                      
{                                                                               
   default   steadyState;                                                       
}                                                                               
                                                                                
divSchemes                                                                      
{                                                                               
   default   none;                                                              
   div(phi,U)   bounded Gauss upwind grad(U);                                   
   div(phi,nuTilda)   bounded Gauss upwind grad(nuTilda);                       
   div((nuEff*dev2(T(grad(U)))))   Gauss linear;                                
   div(phi,T)    bounded Gauss upwind;                                          
}                                                                               
                                                                                
gradSchemes                                                                     
{                                                                               
   default   Gauss linear;                                                      
}                                                                               
                                                                                
interpolationSchemes                                                            
{                                                                               
   default   linear;                                                            
}                                                                               
                                                                                
laplacianSchemes                                                                
{                                                                               
   default   Gauss linear corrected;                                            
}                                                                               
                                                                                
snGradSchemes                                                                   
{                                                                               
   default   corrected;                                                         
}                                                                               
                                                                                
wallDist                                                                        
{                                                                               
   method   meshWave;                                                           
}

Thanks to all of you!