Channel flow with two opposite symmetric bumps at medium Reynolds number

Channel flow with two narrowing sections at medium Reynolds number, starting from rest. Both bumps are symmetric and opposite, and their height is 0.35, while the free section inbetween has width 0.3. The flow shows a nonperiodical behaviour, changing between "symmetric" breakdown near the bumps and a preferred flow direction (mainly) downwards. This tendency may be coincidental since for other calculations with equivalent configurations, the flow exhibited similar behaviour, but going either up or down.

• Distribution of temperature/concentration via Boussinesq model
  
  

  Visualization via distribution of the temperature in the flow field, starting from the heated walls (first, shaded, 2.7 MB, second as a zoom with isolines, 16.8 MB), or via starting particles at the inlet (third and fourth with different color maps, shaded, 1.8 MB and 2.1 MB).
  

  
  
  
  
  
  

  
  
  
  
  
  
  

• Pressure
  
  

  Visualization via pressure plots, shaded (first, 1.8 MB) and via isolines (second, 6.5 MB).
  

  
  
  
  
  
  
  

• Streamfunction
  
  

  Visualization via streamline plots, shaded (first, 2.4 MB) and via isolines (second, 12.7 MB).
  

  
  
  
  
  
  
  

• Velocity
  
  

  Visualization via vector plots (first, 18.8 MB), and as a zoom (second, 19.0 MB).