[saifullahkhalid]

Hello Everyone!

I am trying to simulate flow over plunging airfoil in ANSYS Fluent. Using dynamic meshing, mesh becomes much distorted (sometimes to unacceptable limits) for high amplitude motion. To avoid this situation, accelerated reference frame method seems to be a good solution. For that matter, oscillating y-velocity component along with constant x-velocity is required to be given at inlet, upper and lower boundaries (in case of H- or C-grid). I have been following the work of Thomas Kinsey (University Laval, Quebec, 2011) and Ashraf (UNSW, Australia, 2010) where they have tried to implement this method in Fluent. I have faced a serious issue with this method while I am trying to use it for 1000 Reynolds number. The problem is the implementation of surface pressure gradient condition on airfoil described by Blacksburn and Henderson, 1999 ( http://authors.library.caltech.edu/2100/1/BLAjfm99.pdf ) . This boundary condition must be applied along the normal direction of airfoil. It relates this normal pressure gradient at the surface with the acceleration of airfoil. For accelerated reference frame, acceleration term has to be added as a source in y-momentum equation which I have already done. UDFs, used by these two PhDs are given at the end of their dissertation. Any help would be highly appreciated.

Thanks in anticipation!