Xiao Sun^a, Fan-Kang Zeng^a, Jia-Bing Yang^a, Feng-Lin Zhou^a, Yu-Liang Zhang^b,*

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-6, 2021, DOI:10.5098/hmt.17.5

Abstract In order to better study the internal flow characteristics of centrifugal pump as turbine, CFX software is employed to carry out numerical simulation to obtain flow field under different working conditions for pump as turbine based on the standard k - epsilon turbulence model and the SIMPLEC algorithm. The efficiency curves of the pump and pump as turbine are obtained under different working conditions. The results show that the effciency characteristics of the pump change greatly during the process of pumping. The efficiency of the turbine is higher than that of the pump under the respective optimal operating conditions. The… More >

O. M. Oyewola^a,b,* , O. S. Ismail^b , M. O. Olasindeb , O. O. Ajide^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.30

Abstract In this work, attempt is made to investigate the effect of cylindrical arrangement on the thermal and flow fields within the mixed convective regime for different values of Reynolds number within the study zone. Constructal design was used to design the flow geometric. Two-dimensional unsteady laminar flow equations with buoyancy force were solved numerically using finite element technique implemented on ANSYS FLUENT software. The study showed an optimised arrangement of 50% difference in coefficient of drag and 10% difference in Nusselt number within the geometrical arrangement variation. The effect of geometric arrangement is pronounced at low Ri than at high… More >

Ningxiang Lu, Jinwang Li^*, Yongkang Sun

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-15, 2022, DOI:10.5098/hmt.18.24

Abstract Heat pipe is a kind of high-efficiency heat transfer element which depends on the phase change of its internal working liquid. It has the characteristics of high heat conductivity and excellent average temperature performance. As the core component of heat pipe, capillary wicks play the role of transmitting working fluid and have a crucial impact on the heat transfer performance of heat pipe. In this paper, the research progress of capillary wicks in recent years is introduced from the aspects of structure, fabrication method, performance research, numerical analysis and so on. The current research results of capillary wicks are summarized,… More >

Mohammed Z. Swalmeh^*

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.12

Abstract Heat transfer characteristics for free convection boundary layer flow with a Ferro-hybrid nanofluid in the Casson field, over a stretching sheet, have been numerically investigated and tested. The constant wall temperature boundary condition was applied in this study. The dimensional governing equations were transformed to partial differential equations (PDEs) and then solved numerically by an implicit finite difference scheme known as Keller box method. The Numerical findings were presented by tabular and figures by using MATLAB program. These numerical findings were gained according to considering and analyzing the impacts of Ferro-hybrid nanofluids Casson parameters, on the local skin friction coefficient… More >

M. O. Petinrin^a , B. A. Sikirullahi^a, T. T. Olugasa^a, O. M. Oyewola^a,b,*

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.28

Abstract Tubes are commonly employed in heat exchangers for their ease of production and capacity to sustain high pressure. In this study, the heat and flow transfer behaviour of cam-shaped tube bank in staggered configuration at varying angles of attack 0°to 180° was numerically investigated. The study was carried out by solving the continuity, momentum, energy and realizable k-ε transport equations using the finite volume-based ANSYS Fluent solver. This was performed to acquire the friction factor and heat transfer characteristics in the air inlet velocity range of 9 to 15 m/s. The results showed that the cam-shaped tube bank at varying… More >

Roshan Devidas Bhagat^a,* , Samir J. Deshmukhsup>b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-11, 2022, DOI:10.5098/hmt.19.14

Abstract Numerical analysis of liquid vapor slug flow in a vertically placed U-shaped closed capillary tube is carried out with family of hydrocarbon fluid like Acetone, Ethanol, Methanol and Pentane. A 3D computational domain has been developed for vertically placed U-shaped capillary tube sealed at both end with three small turns in evaporator section, two small and one large turn in condenser section. The diameter of vertically placed U-shaped capillary tube is taken as 2mm. The volume of fluid (VOF) approach, suitable model of K-epsilon is used to predict the behavior of liquid vapor slug flow along the wall of capillary… More >

A. Lkouen^1,*, M. Lamrani², A. Meskini¹, A. Khabbazi³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 2013-2026, 2023, DOI:10.32604/fdmp.2023.026929

Abstract Most of the energy savings in the building sector come from the choice of the materials used and their microphysical properties. In the present study, through numerical simulations a link is established between the thermal performance of composite materials and their microstructures. First, a two-phase 3D composite structure is modeled, then the RSA (Random Sequential Addition) algorithm and a finite element method (FE) are applied to evaluate the effective thermal conductivity of these composites in the steady-state. In particular, building composites based on gypsum and clay, consolidated with peanut shell additives and/or cork are considered. The numerically determined thermal conductivities… More > Graphic Abstract

Ningbo Guo, Xianming Gao^*, Duanling Li, Jixing Zhang, Penghui Yin, Mengyi Hua

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 3061-3082, 2023, DOI:10.32604/cmes.2023.026657

Abstract Computational fluid dynamics was used and a numerical simulation analysis of boiling heat transfer in microchannels with three depths and three cross-sectional profiles was conducted. The heat transfer coefficient and bubble generation process of three microchannel structures with a width of 80 μm and a depth of 40, 60, and 80 μm were compared during the boiling process, and the factors influencing bubble generation were studied. A visual test bench was built, and test substrates of different sizes were prepared using a micro-nano laser. During the test, the behavior characteristics of the bubbles on the boiling surface and the temperature… More >

Ridwan¹, Sher Afghan Khan^1,*, Jaffar Syed Mohamed Ali¹, Mohd. Azan Mohammed Sapardi¹, Abdul Aabid²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1655-1678, 2023, DOI:10.32604/fdmp.2023.025230

Abstract In the present study, the base pressure variations induced by the presence of a cavity, known to have a strong influence of the behaviour of supersonic projectiles, are investigated through numerical solution of the balance equations for mass, momentum, and energy. An area ratio of four is considered and numerical simulations are carried out at Mach M = 1.2, 1.4, 1.6, and 1.8 assuming no cavity or cavity locations 0.5D, 1D, 1.5D, and 2D. The inlet pressure of the nozzle is considered as a flow variable. The Taguchi method is also used, and the considered cases are then analyzed using… More >

Muhammad Tariq Ali¹, Dumitru Baleanu^2,3,4, Muhammad Rafiq⁵, Jan Awrejcewicz⁶, Nauman Ahmed⁷, Ali Raza^8,*, Muhammad Sajid Iqbal⁹, Muhammad Ozair Ahmad⁷

Intelligent Automation & Soft Computing, Vol.36, No.2, pp. 1479-1496, 2023, DOI:10.32604/iasc.2023.033157

Abstract The human immunodeficiency viruses are two species of Lentivirus that infect humans. Over time, they cause acquired immunodeficiency syndrome, a condition in which progressive immune system failure allows life-threatening opportunistic infections and cancers to thrive. Human immunodeficiency virus infection came from a type of chimpanzee in Central Africa. Studies show that immunodeficiency viruses may have jumped from chimpanzees to humans as far back as the late 1800s. Over decades, human immunodeficiency viruses slowly spread across Africa and later into other parts of the world. The Susceptible-Infected-Recovered (SIR) models are significant in studying disease dynamics. In this paper, we have studied… More >