Elyazid Flilihi^a,† , Mohammed Sriti^b, Driss Achemlal^a, Mohamed El haroui^c

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-6, 2021, DOI:10.5098/hmt.17.7

Abstract In this work, a numerical simulation of steady and laminar free convection flow over a heated vertical flat plate embedded in a saturated porous medium by a Newtonian fluid is presented and analyzed. The Brinkman-Forchheimer extension of Darcy’s law has been adopted to describe the movement of fluid within the porous matrix. A numerical solution of the governing continuity, momentum and energy equations was made with the appropriate boundary conditions using ANSYS/FLUENT software based on finite volume method. The found results are graphically presented and physically discussed for main controling parameters. Subsequently, we compared our CFD calculation by the results… More >

Abderraouf Dahmani^a,∗ , José Muñoz-Cámara^b, Juan Pedro Solano^b, Samir Laouedj^a

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.42

Abstract In this paper, a steady and laminar flow of ferrofluid (Fe₃O₄/Water) in a uniformly heated tube under the effect of non-uniform magnetic field arranged periodically along the tube is numerically analyzed using the finite volume method. The analysis sheds light on the flow pattern, Nusselt number, friction factor and the Performance Evaluation Criterion, at laminar flow regime (10² ≤ Re ≤ 10³ ) and for various magnetic numbers (Mn = 0, 2.83 · 10⁴ , 6.37 · 10⁴ and 1.13 · 10⁵ ). The obtained results show that the magnetic field generated by periodic arrangement of the wire pitches, forces… More >

E. Flilihi^a,† , E. H. Sebbar^a, D. Achemlal^a, T. EL Rhafiki^a, M. Sriti^b, E. Chaabelasri^c

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.39

Abstract In this paper, we made a numerical simulation of convective heat transfer in a rectangular section pipe of a air flat plate solar collector using three forms of the absorber plate namely, simple shape, rectangular-shape, and half circle-shape. The flow is considered laminar and stationary, where the heat exchange between the absorber plate and the fluid takes place in useful area. The computer code in fluid dynamics, the fluent, is applied to integrate the governing equations on each control volume. A detailed description of the fluid flow and heat transfer in the rectangular channel was made. Several simulation were carried… 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 >

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 >

Tounsi Chati^a,* , Kouider Rahmani^b, Toufik Tayeb Naas^c, Abdelkader Rouibah^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-11, 2022, DOI:10.5098/hmt.18.19

Abstract Numerical results of turbulent natural convection and mass transfer in an open enclosure for different aspect ratios (AR = 0.5, 1, and 2) with a humidair are carried out. Mass fraction and local Nusselt number were proposed to investigate the heat and mass transfer. A heat flux boundary conditions were subjected to the lateral walls and the bottom one make as an adiabatic wall, while the top area was proposed as a free surface. Effect of Rayleigh numbers (10⁶ ≤ More >

Albio D. Gutierrez^a,*, Hayri Sezer^b, Jose L. Ramirez^c

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-12, 2022, DOI:10.5098/hmt.18.4

Abstract This paper presents a computational model along with a thermal comfort criterion aimed at assisting the design of operating rooms (ORs) from the perspective of meeting suitable flow patterns and thermal comfort conditions for the occupants. The computational model is based on the finite volume method (FVM) to describe the air inside ORs along with the human thermoregulation model implemented in virtual mannequins for thermal comfort. The air model considers turbulent fluid motion, species transport and the conservation of energy, including thermal radiation. The human thermoregulation model incorporates two interacting systems of thermoregulation. Namely, the passive system and the active… More >

Kamyar Mohammadpour^*, Ali Chitsazan, Eckehard Specht

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.37

Abstract The length of flame and behavior of the flame and homogenization in temperature distribution play the main roles to obtain a better quality of lime. Performing experiments in a real lime shaft kiln plant are quite complicated. A lime shaft kiln normally has a large geometry, including a height of 15 meters and a diameter of 3 meters, and is filled with large stones moving in a vertical direction. In most cases, the measuring instruments are damaged. Due to these difficulties, modeling of physical and chemical processes is required for having a better understanding of the process and optimizing the… More >

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

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.35

Abstract The objective of the present research is the prediction of large arrays of impingement jets using a computational model. The heat transfer and the force coefficient from single and multiple jet rows (1, 2, 4, 8, and infinity rows) for two different nozzle shapes as either orifice or straight pipe on a fixed flat surface were numerically investigated for drying applications to understand the physical mechanisms which affect the uniformity of the local heat transfer and pressure force coefficient as well as average heat transfer coefficient. The pipe has always a higher averaged Nu and pressure force coefficient compared to… More >

Andrés Zapata^a , Carlos Amaris^b,*, Alexis Sagastume^a, Andrés Rodríguez^a

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-9, 2022, DOI:10.5098/hmt.19.33

Abstract The present study aims to assess the vapour bubble absorption into the ammonia/lithium nitrate (NH₃/LiNO₃) solution by using an optimized CFD model. A detailed methodology to build up the CFD model is presented, as well as its validation using experimental data. The operating conditions set corresponds to an absorption chiller driven by low-temperature heat sources such as solar energy in warm environments. Results evidenced that the Volume of Fluid and Mixture models are adequate to be used in the CFD model to predict the absorption process in the bubble absorber assessed depending on the mesh density refinement. Moreover, the heat… More >