mesh quality
 

I would appreciate if some one can kindly give me some tip or guide me how to resolve my icem cfd mesh quality problems. I am a novice user of ICEM cfd and this is my first project with this meshing software. I have extracted a fluid domain from inside a refrigerator using design modeler. I have split block to every curve of the geometry and then delete and associate edges to the available curves. I did not use any o-grid. After updating the pre mesh params , I am getting very bad quality triangular mesh at some surfaces, while I am expecting to get all hex mesh. I tried to merge some blocks which helps to remove only one of these issue but the other does not get effect from merge block. I have also tried pre mesh smooth but that also does not help to cure the problems.

provide me geometry. i can look into it