Post processing toolbox for 2d and 3d DNS and experimental results of turbulent reacting flows

Documentation and tutorial - Example and guide to use the tools

Example for the investigation of a 3 dimensional non-premixed, turbulent H2/air flame.

• First define and locate the flamefront:

  • e.g. along the stoichiometric isolevel of the mixture fraction f at f=0.5
    between the upper boundary Z=0.8 and the lower boundary Z=0.1:
    [og,ug]=flamefront3 (X,Y,Z,f,0.5,'abs',0.8,0.1)

  • and calculate the flame surface area
    [Area]=surfarea (X,Y,Z,f,0.5)

• Second compute or extract important variables along the flamefront

  • e.g. extract the flame index along flamefront defined by f=0.5;
    [inn,variso]=flameindex3 (X,Y,Z,Y_H2,Y_O2,f,'abs','yes')
  • compute strainrate along flamefront:
    [str3ff]=strnlev3 (X,Y,Z,strt,f,0.5,'abs')

• Then draw linear cuts through flame front between boundaries defined above

  • extract variables for example heatr along these cuts
    [XMIN,XMAX,YMIN,YMAX,ZMIN,ZMAX,XX1,YY1,ZZ1,VV1,VV2,VVG]=lincut3 (X,Y,Z,0.0062,0.004887,0.0.0048,-0.4936,-0.8846,0.2071,f,heatr,0.0001,0.5,'abs',0.8,0.1);
  • compute integral value of heat release along the cut
    intvar=intcutlin3 (X,Y,Z,0.0062,0.004887,0.0048,-0.4936,-0.8846,0.2071,f,heatr,0.0001,0.5,'abs',0.8,0.1)
  • compute flamethickness along linear cuts, use batch modus
    [flthick3,mathick,mithick,meanthick]=flamethicklin3b2 (X,Y,Z,f,0.5,'abs',0.8,0.1)

• Then draw nonlinear cuts through the flame front
  [XMIN,XMAX,YMIN,YMAX,ZMIN,ZMAX,XX1,YY1,ZZ1,VV1,VV2,VVG]=nonlincut3 (X,Y,0.0062,0.004882,0.0048,f,Y_H2O2,0.0001,0.5,'abs',0.8,0.1)

  • extract variables for example the mass fraction of the radical H2O2 along the cuts
• Then do some statistical investigation
  • plot correlation between variables extracted along a linear cut, e.g. heat release and mass fraction of the radical OH:
    [cc]=correlationgen3(heatr,Y_OH)
  • compute mean, minimum, maximum and rms values of a variable e.g. heatrelease conditioned on f
    [cc,m,rms,mi,ma]=condmean3filt (X,Y,Z,f,heatr,0.01)
  • Investigate the velocity field. Plot amount and direction of the velocity vectors as cones.
    []=coneplot3 (x_velocity,y_velocity,z_velocity,X,Y,Z)