O. M. Oyewola^a,b,*, S. I. Afolabi^b, O. S. Ismail^b, M.O. Olasinde^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-7, 2022, DOI:10.5098/hmt.18.31

Abstract Finite element method is adopted in analyzing a two dimensional partial differential equations of Navier Stokes that governs mass, momentum and energy for a convective heat transfer problem within a square cavity. The cavity walls kept at constant cold temperature except for the right wall being adiabatic. With an embedded circular heated block located in the cavity, simulations are performed to determine the effect of the position of the block at the top, middle and bottom of the cavity on natural convection. The experiments are carried out for different values of Rayleigh number varying from 10³ – 10⁶ by using… More >

Shintaro Hayakawa^a , Takashi Fukue^a,*,† , Yasuhiro Sugimoto^a , Wakana Hiratsuka^b , Hidemi Shirakawa^c , Yasushi Koito^d

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-9, 2022, DOI:10.5098/hmt.18.29

Abstract This paper describes the effects of a combination of rib and pulsating flow on heat transfer enhancement in an mm-scale model that simulates the narrow flow passages in cooling devices of downsized electronic equipment. This research aims to develop a novel water cooling device that increases heat transfer performance while inhibiting pumping power. Our recent study has reported that a combination of pulsating flow and rib could enhance heat transfer performance relative to the simple duct. In the present study, to verify the optimal rib height for improving heat transfer by pulsating flow, we evaluated the relationship between heat transfer… More >

Fithry Mohd Amir^*, Mohd Zamri Yusoff, Saiful Hasmady Abu Hassan

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-15, 2022, DOI:10.5098/hmt.18.27

Abstract Nanofluid film on a horizontal tube is investigated numerically on the circular and multi-faceted cylinder. The fluid flow characteristics, including film thickness, shear stress, and thermal performance, are observed and analyzed. Fluid film on the circular surface is typical in many engineering applications, but the study of nanofluid film on non-circular surface is deficient in literature. The study provides a numerical model of a multi-faceted cylinder to simulate the nanofluid film on the non-circular surfaces using a volume of fluid (VOF) method. The ratio of Brownian motion to thermophoretic diffusion, N_BT developed along the film thickness in phases, in which… More >

Erdiwansyah Erdiwansyah^a,d , Mahidin Mahidin^b, Husni Husin^b, Muhammad Faisal^c, Usman Usman^c, Muhtadin Muhtadin^c, Asri Gani^b,*, Rizalman Mamat^e

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.25

Abstract The modification of the perforated plate applied in this study aims to provide sufficient air access into the combustion chamber. Burning experiments were carried out with three different types of fuel (such as palm kernel shell (PKS), oil palm midrib (OPM), and empty fruit bunches (EFB). The purpose of the experiment with the modification of the perforated plate is to investigate the combustion temperature and the rate of heat transfer in the boiler. The fluidized-bed combustor (FBC) combustion chamber is used as the combustion chamber. Experimental results were obtained at four different points using a Digital Thermometer with a thermocouple.… More >

Mei Su^a , Ligai Kang^b, Kangjie Sun^b,*

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-5, 2022, DOI:10.5098/hmt.18.22

Abstract To study the heat transfer effect of rough surface in laminar flow, the direction splitting method is introduced by fully developed fields for solving the Navier–Stokes equations of incompressible flow in assuming two-dimension. Firstly, the algorithm of the incompressible Navier–Stokes equations with pressure correct is carried out. Secondly, the effects of pressure drop and heat transfer are investigated in different rough surface elements which are configured with triangular and rectangular elements. The Reynolds number, roughness element spacing, and roughness height are also considered as the factors which affect the heat transfer. The results indicate that the parallel present method reaches… More >

Amnart Boonloi^a, Withada Jedsadaratanachai^b,*

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-15, 2022, DOI:10.5098/hmt.18.20

Abstract Numerical analysis of fluid flow mechanism and heat transfer in a heat exchanger duct (HXD) with dual-inclined baffles (DIB) are reported. Three DIB types are examined: 1. “Type A” is located at the center of the HXD, 2. “Type B” is located on the upper-lower duct walls (as an orifice) and 3. “Type C” is a combination of the type A and B (as double orifices). The impacts of the ratio of DIB heights (b) to the square duct height (H; b/H) on increased heat transfer and friction loss are analyzed. Laminar flow (Re = 100 – 2000 based on… More >

Bhagawan Singh Yadav, Sushila Choudhary^†

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-10, 2022, DOI:10.5098/hmt.18.18

Abstract The present study concentrates on squeeze MHD flow of Casson fluid between parallel plates surrounded by a porous medium. The influence of melting, viscous dissipation and thermal radiation on the heat transfer process is disclosed. The characteristics of mass transport are detected with chemical reactions. Suitable similarity transforms are used to convert the partial differential equations into a system of ordinary differential equations. The transformed equations are solved using the bvp4c matlab solver with the shooting method. Our present study concluded that fluid velocity has direct relation with melting parameter while it is reciprocally related to squeezing parameter and reverse… More >

Ali Chitsazan^a , Georg Klepp^a, Mohammad Esmaeil Chitsazan^b, Birgit Glasmacher^c

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.17

Abstract For the optimization of the impinging round jet, the pressure force coefficient and drying energy consumption on the moving curved surface are set as the objective functions to be minimized simultaneously. SHERPA search algorithm is used to search for the optimal point from multiple objective tradeoff study (Pareto Front) method. It is found that the pressure force coefficient on the impingement surface is highly dependent on the jet to surface distance and jet angle, while the drying energy consumption is highly dependent on the jet to jet spacing. Generally, the best design study during the multi-objective optimization is found at… More >

Ali Chitsazan^a, Georg Klepp^a, Birgit Glasmacher^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-9, 2022, DOI:10.5098/hmt.18.16

Abstract The effect of jet Reynolds number, jet exit angle, the nozzle to surface distance, jet to jet spacing on the heat transfer, and pressure force performance from multiple impinging round jets on a moving curved surface have been numerically evaluated. Two correlations are developed and validated for the average Nu number and the pressure force coefficient and the agreement between the CFD and correlations was reasonable. The surface motion effect becomes more pronounced on the Nu number distribution for low jet Re number, high jet to jet spacing, large jet to surface distance, and angled jets. The pressure force coefficient… More >

Ali Chitsazan^a , Georg Klepp^a, Birgit Glasmacher^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-7, 2022, DOI:10.5098/hmt.18.15

Abstract The effect of surface curvature, number of jets, number of jet rows, jet arrangement, crossflow, and surface motion on the heat transfer and pressure force performance from multiple impinging round jets on the moving flat and curved surface have been numerically evaluated. The more number of jets (more than three jets) has no significant effect on the average heat transfer rate. The more number of jet rows increases the strength of wall jets interference and crossflow effects and degrade the average heat transfer rates. There is a minor difference between inline and staggered arrangements on both moving flat and curved… More >