Aspect ratio effects in Rayleigh–Bénard convection of Herschel–Bulkley fluids

Author:

Aghighi Mohammad Saeid,Ammar Amine

Abstract

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 model. Design/methodology/approach In this study, a numerical method based on the finite element has been developed for analyzing two-dimensional natural convection of a Herschel–Bulkley fluid. The effects of Bingham number Bn and power law index n on heat and momentum transport have been investigated for a nominal Rayleigh number range (5 × 103 < Ra < 105), three different aspect ratios (ratio of enclosure length:height AR = 1, 2, 3) and a single representative value of nominal Prandtl number (Pr = 10). Findings Results show that the mean Nusselt number Nu¯ increases with increasing Rayleigh number due to strengthening of convective transport. However, with the same nominal value of Ra, the values of Nu¯ for shear thinning fluids n < 1 are greater than shear thickening fluids n > 1. The values of Nu¯ decrease with Bingham number and for large values of Bn, Nu¯ rapidly approaches unity, which indicates that heat transfer takes place principally by thermal conduction. The effects of aspect ratios have also been investigated and results show that Nu¯ increases with increasing AR due to stronger convection effects. Originality/value This paper presents a numerical study of Rayleigh–Bérnard flows involving Herschel–Bulkley fluids for a wide range of Rayleigh numbers, Bingham numbers and power law index based on finite element method. The effects of aspect ratio on flow and heat transfer of Herschel–Bulkley fluids are also studied.

Publisher

Emerald

Subject

Computational Theory and Mathematics,Computer Science Applications,General Engineering,Software

Reference23 articles.

1. Parametric solution of the Rayleigh-Benard convection model by using the PGD application to nanofluids;International Journal of Numerical Methods for Heat & Fluid Flow,2015

2. Non-incremental transient solution of the Rayleigh-Bénard convection model by using the PGD;Journal of Non-Newtonian Fluid Mechanics,2013

3. Les tourbillons cellulaires dans une nappe liquide;Revue Generale Des Sciences Pures Et Appliquees,1900

4. Non-linear properties of thermal convection;Reports on Progress in Physics,1978

Cited by 8 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

1. Wall slip effects in Rayleigh–Bénard convection of viscoplastic materials;Multidiscipline Modeling in Materials and Structures;2023-10-13

2. Double-diffusive natural convection of Casson fluids in an enclosure;International Journal of Mechanical Sciences;2022-12

3. Note on the Early Thermoelastic Stage Preceding Rayleigh–Bénard Convection in Soft Materials;Fluids;2022-07-08

4. Rayleigh–Bénard convection of a viscoplastic liquid in a trapezoidal enclosure;International Journal of Mechanical Sciences;2020-08

5. Natural convection of Casson fluid in a square enclosure;Multidiscipline Modeling in Materials and Structures;2020-04-05

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3