Rayleigh–Bénard convection of a viscoplastic liquid in a trapezoidal enclosure
Article dans une revue avec comité de lecture
JournalInternational Journal of Mechanical Sciences
.The objective of this paper is to clarify the role of sloping walls on convective heat transport in Rayleigh–Bénard convection within a trapezoidal enclosure filled with viscoplastic fluid. The rheology of the viscoplastic fluid has been modeled with Bingham fluid model. The system of coupled nonlinear differential equations was solved numerically by Galerkin's weighted residuals scheme of finite element method. The numerical experiments are carried out for a range of parameter values, namely, Rayleigh number (5.103 ≤ Ra ≤ 105), yield number (0 ≤ Y ≤ Yc), and sidewall inclination angle (ϕ = 0, π/6, π/4, π/3) at a fixed Prandtl number (Pr = 500). Effects of the inclination angle on the flow and temperature fields are presented. The results reveal that inclination angle causes a multicellular flow and appears as the main parameter to govern heat transfer in the cavity. The heat transfer rate is found to increase with the increasing angle of the sloping wall for both Newtonian and yield stress fluids. On the other hand, the plug regions also found to increase with increasing φ, which is unusual but perhaps not unexpected behavior. In the yield stress fluids, the flow becomes motionless above a critical yield number Yc because the plug regions invade the whole cavity. The critical yield number Yc is also affected by the change of inclination angle and increases significantly with the increase of φ.
Files in this item
Showing items related by title, author, creator and subject.
Article dans une revue avec comité de lectureThis study investigates the double-diffusive natural convection of the non-Newtonian Casson fluid in a square cavity based on the original viscoplastic stress model without simplification. Therefore, yield stress plays an ...
Article dans une revue avec comité de lectureAGHIGHI, Mohammad Saeid; AMMAR, Amine; METIVIER, Christel; GHARAGOZLU, M. (Elsevier, 2018)This study aims at investigating numerically the Rayleigh-Bénard Convection (RBC) in viscoplastic fluids. A Casson fluid is considered in a bidimensional square cavity heated from below. The effects of the dimensionless ...
Article dans une revue avec comité de lectureAGHIGHI, Mohammad Saeid; AMMAR, Amine (Emerald, 2017)Purpose The purpose of this paper is to analyze two-dimensional steady-state Rayleigh–Bénard convection within rectangular enclosures in different aspect ratios filled with yield stress fluids obeying the Herschel–Bulkley ...
Parametric solution of the Rayleigh-Benard convection model by using the PGD Application to nanofluids Article dans une revue avec comité de lectureAGHIGHI, Mohammad Saeid; AMMAR, Amine; METIVIER, Christel; CHINESTA, Francisco (Emerald, 2015)Purpose – The purpose of this paper is to focus on the advanced solution of the parametric non-linear model related to the Rayleigh-Benard laminar flow involved in the modeling of natural thermal convection. This flow is ...
Article dans une revue avec comité de lectureAGHIGHI, Mohammad Saeid; AMMAR, Amine; METIVIER, Christel; NORMANDIN, Magdeleine; CHINESTA, Francisco (Elsevier, 2013)This paper focuses on the non-incremental solution of transient coupled non-linear models, in particular the one related to the Rayleigh–Bénard flow problem that models natural thermal convection. For this purpose we are ...