Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
Numerical simulation of mixed convection from a cylinder immersed in viscoplastic fluids
Submission Author:
Daniel Dall Onder dos Santos , MG , Brazil
Presenter: Daniel Dall Onder dos Santos
doi://10.26678/ABCM.ENCIT2016.CIT2016-0664
Abstract
The study of convection heat transfer involving viscoplastic fluids have raised a lot of attention in the recent years thanks to the huge economic importance on areas like the food, health care and oil industries, as well as biomedical engineering. Emulsions, suspensions and foams are common examples of this class of materials. From the heat transfer point of view, the abrupt changes in the viscosity presented by this class of fluids affects the flow field and consequently, the amount of thermal energy that can be carried by the fluid. In the other hand, the flow conditions around an immersed body can modify the heat transfer regime from or to forced, mixed and free convection. The relative importance of the forced and free convection contributions in the mixed convection regime is expressed using the Richardson number. This work aims to perform numerical simulations of non-isothermal two-dimensional steady state laminar flows over a cylinder immersed on viscoplastic fluids. The mechanical model is defined by the mass, momentum and energy balance equations coupled to the SMD equation to model the viscoplastic behavior. This modeling is approximated by a stabilized multi-field Galerkin finite element methodology, having as primal variables the velocity, pressure, extra-stress and temperature fields. In the performed numerical simulations, the governing parameters, namely the Reynolds, Herschel-Bulkley and Richardson parameters are varied in order to evaluate their influence on the cylinder heat transfer and flow unyielded regions.
Keywords
Viscoplastic flow, Mixed Convection, Finite Element Method, SMD model
