Hosseinzadeh Kh, Roshani M, Attar M A, Ganji D D, Shafii Mohammad Behshad
Department of Mechanical Engineering, Sharif University of Technology, Azadi Ave, Tehran, Iran.
Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran.
Heliyon. 2023 Sep 15;9(9):e20193. doi: 10.1016/j.heliyon.2023.e20193. eCollection 2023 Sep.
Nowadays, several engineering applications and academic investigations have demonstrated the significance of heat transfers in general and mixed convection heat transfer (MCHT) in particular in cavities containing obstacles. This study's main goal is to analyze the MCHT of a nanofluid in a triangular cavity with a pentagonal barrier using magneto hydrodynamics (MHD). The cavity's-oriented walls are continuous cold temperature, whereas the bottom wall of the triangle and all pentagonal obstacle walls are kept at a constant high temperature. For solving governing equations, we utilized the Galerkin's finite element approach. Four dimensionless factors, Richardson number (0.01 ≤ Ri ≤ 5), Reynolds number (10 ≤ Re ≤ 50), Buoyancy ratio (0.01 ≤ Br ≤ 10) and Hartmann number (0 ≤ ≤20) are examined for their effects on streamlines, isotherms, concentration, velocity, and the Nusselt number. Also, with the help of Taguchi method and Response Surface Method (RSM) the optimization of the studied dimensionless parameters has been done. The optimum values of Ri, Re, and Br are obtained 4.95, 30.49,18.35 and 0.05 respectively. Ultimately, a correlation has been extracted for obtaining the optimum average Nusselt number () in mentioned cavity.
如今，一些工程应用和学术研究已经证明了一般热传递，特别是混合对流热传递（MCHT）在包含障碍物的空腔中的重要性。本研究的主要目标是使用磁流体动力学（MHD）分析具有五边形障碍物的三角形空腔中纳米流体的混合对流热传递。空腔的定向壁保持连续低温，而三角形的底壁和所有五边形障碍物壁保持在恒定高温。为了求解控制方程，我们采用了伽辽金有限元方法。研究了四个无量纲参数，即理查森数（0.01≤Ri≤5）、雷诺数（10≤Re≤50）、浮力比（0.01≤Br≤10）和哈特曼数（0≤Ha≤20）对流线、等温线、浓度、速度和努塞尔数的影响。此外，借助田口方法和响应面法（RSM）对所研究的无量纲参数进行了优化。Ri、Re、Ha和Br的最佳值分别为4.95、30.49、18.35和0.05。最终，提取了一个关联式，用于获得上述空腔中的最佳平均努塞尔数（Nu）。
