The major objective of this work is to develop accurate computational models to predict evolution of shear thinning liquid jets. A secondary objective is to investigate the formation of satellite drops, and to determine the conditions under which their diameter can be controlled. The theoretical approach of Galerkin-finite element analysis is used solve the complete two-dimensional set of axisymmetric governing equations and the kinematic and dynamic boundary conditions at the free surface. The effect of shear thinning behavior on break-up is studied in detail, in the case of an infinitely long non-Newtonian jet. It is found that the shear thinning behavior may be useful in controlling satellite drop sizes. (We observe that increasing the shear thinning behavior at moderate Reynolds number (Re = 5) leads to an initial increase in the satellite drop size, followed by a subsequent decrease.) Experimental validation for the theory is then presented for the case of a shear thinning non-Newtonian jet. The experimental fluid is pumped through a capillary and drop shapes are obtained using a high speed camera. The experimentally obtained shapes are compared to those predicted by theory with results found to be in good agreement.

Volume Subject Area:
Fluids Engineering
Topics:
Jets, Reynolds number, Shear (Mechanics), Satellites, Shapes, Boundary-value problems, Fluids, Kinematics
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