Different Applied Boundary Condition Within SSHE Treating Non-Newtonian Shear Thinning Fluid

摘要

Scraped surface heat exchanger (SSHE) is widely spread in different chemical, food pharmaceutical and petrochemical industry. The attractive feature behind its design is their capability to handle highly viscous, sensitive, sticky product and slurry system. A numerical study of the performance of different cooling process (different applied boundary condition) within SSHE equipped with blades was conducted using ANSYSFLUENT 19.0. Three boundary conditions are examined in this study; a constant applied wall temperature, a constant applied heat flux and a variable wall temperature. The cooling process of 2% Carboxylmethyl cellulose (cmc) is investigated under steady state, non-isothermal, laminar flow condition. Numerical simulation shows that the thermal behavior within SSHE is highly dependent on the boundary condition applied at the stator wall. The hydrodynamics behaviour within SSHE is controlled by scraper rotation. The outlet temperature of fluid reaches the desired cooling temperature for a constant applied heat flux, although it was higher for the other applied boundary condition. It is more effective to cool the fluid gradually by applying a variable fluid temperature.