A numerical study of the wall effects for Newtonian fluid flow over a cone

The effect of blockage ratio i.e. ratio of diameter of cone, d and flow channel, D on the drag coefficients due to Newtonian fluid flow over cone is studied numerically by solving the CFD equations in Ansys FLUENT. The drag coefficients (CD) as a function of Reynolds number (Re) and d/D are reported in the range of Re: 0.01-30,000 and d/D: 0.0015-0.9. The obtained CD values are higher for confined flow (high d/D) than unconfined flow. Validity of CDRe2=constant is ascertained for the confined Newtonian fluid flow over the cone. The variations of angle of separation and its effect on the drag coefficients are examined and justified. The comparative studies among the drag coefficients of sphere, cylinder and cone are carried out in terms of wall effect, re-circulation length and slope of axial velocity profile. The observations revealed the order of CD as cylinder > cone > sphere. The hydrodynamic interactions between wall and fluid medium are presented with the help of velocity contour plots. More asymmetric flow is observed around the particle at higher Reynolds number and for higher wall effect. The simulated results presented herein for unconfined flow are in good agreement with the literature data.