anybody know how to fix reverse flow

- October 28, 2020 at 11:10 am
  
  rafijr11
  Subscriber
  
  i tried to simulation to find coefficeint drag and lift to car body, what should i do to fix this reverse flow. Here is my boundary condition and mesh
- October 28, 2020 at 11:39 am
  
  Karthik Remella
  Administrator
  
  Hello,nSince you are modeling an external flow problem, I'd strongly recommend that you extend your overall computational domain further downstream of the car. Your outlet boundary might be in the wake region behind the car.nAlso, please improve the mesh quality. Max skewness should be lower than 0.9 for a good mesh.nAlso, if you haven't seen this example from our Ansys Innovation Courses, I'd recommend that watch the video and test this 2D set-up. nI hope this helps.nThanks.nKarthikn
- October 28, 2020 at 4:41 pm
  
  rafijr11
  Subscriber
  
  i already sizing the mesh but it doesn't work to decrase the skewnes n
- October 28, 2020 at 4:59 pm
  
  Rob
  Forum Moderator
  
  What meshing method are you using? If it's the Hexa Dominant one then change it: it's designed for Mech models where they need a good surface mesh and unfortunately the volume mesh isn't any good for CFD. You also want to read up on wind tunnel domain sizing to get an idea of how big the outer domain needs to be relative to the object of interest. n