Abstract:
This work aims to explore the T-channel momentum and heat transfer characteristics
with the combined effect of Bingham plastic fluids (0.01 Bn 20) behavior and geometrical variation in terms of branching angle (30 deg a 90 deg). The problem has been
solved over a wide range of Reynolds number (50 Re 300) and Prandtl number
(10 Pr 50). For the momentum flow, qualitative and quantitative features are analyzed in terms of streamlines, structure of yielded/unyielded regions, shear rate contours,
plug width and length variation, and local pressure coefficient. These features have been
represented in terms of isotherm patterns, temperature profile, Nusselt number, and its
asymptotic value for heat transfer characteristics. The recirculating flows have been presented here in the vicinity of T-junction, which promote mixing and heat transfer.
Broadly, the size of this zone bears a positive dependence on Re and a. However, fluid
yield stress tends to suppress it. The critical Reynolds and Bingham numbers were found
to be strong functions of the pertinent parameters like a. The inclination angle exerts
only a weak effect on the yielded/unyielded regions and on the recirculation length of
main branch. Results show a strong relationship of the plug width and length with key
parameters and branches. The Nusselt number exhibits a positive relationship with a, Bn,
and Re but for lower Pr in the T-junction vicinity for both branches. Such length indicates
the required optimum channel length for thermal mixing.
