An Insight into the Coanda Flow Through Mathematical Modeling
Flow over Coanda surface is numerically investigated. The adhesion angle of the flow has been determined as a function of flow parameters. The viscous effect and the inertia effect have been analyzed at the boundary layer level. This type of flow is unique in the sense that it incorporates the free-shear flow as well as wall-bounded shear flow. The mechanism of the adhesion of the flow has been investigated in detail. This analysis opens the door for development of the new turbulence model: Some components of the Reynold’s stress exhibit the anisotropic nature of the turbulence at the vicinity of the Coanda surface. Nature of the turbulent length scales was discussed which may help to develop the subgrid scale model for the Large eddy simulation for such type of flow. We have proposed the new technique to alleviate the singularity problem at the verge of boundary layer separation. The highlights of the mathematical model are also that it incorporates the dual jet side by side on the curved surface, and turbulent nature of the jet was taken into account by set of boundary conditions.
KeywordsCoanda flow Wall shear stress Boundary layer Cauchy problem Laminar boundary layer Navier-Stokes equation Turbulent length scale
The present work has been performed as part of the ACHEON Project | ACHEON Project—Aerial Coanda High Efficiency Orienting-jet Nozzle project, with ref. 309041 supported by the European Union through the Seventh Framework Program. The first author is highly indebted to Department of Science and methods in engineering. University of Modena and Reggio Emilia, Italy for the support of this work. The first author also would like to thanks to Dr. Andrea Andrisani for constructive advice on numerical computation.
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