Kafel Azeez Mohammed^a,*, Ahmed Mustaffa Saleem^b , Zain alabdeen H. Obaid^a

Frontiers in Heat and Mass Transfer, Vol.16, pp. 1-8, 2021, DOI:10.5098/hmt.16.20

Abstract Numerical investigation is performed for the determination of Nusselt number of ZnO, TiO₂ and SiO₂ nanoparticles dispersed in 60% ethylene glycol and 40% water inside inclined cylinder for adiabatic and isothermal process. The present study was conducted for both the constant heat flux (10,000 W/m²) and constant wall temperature (313.15 K) boundary conditions. At the inlet, the uniform axial velocity and initial temperature (293 K) were assumed. The results show the change of average Nusselt number at Reynolds number (400), Rayleigh number (10⁶) and volume fraction percentage (2%). From results for adiabatic process when increasing the slop up to (45o),… More >

Husam Abdulrasool Hasan^a,*, Jenan S. Sherza^a, Lammiaa Abdulrudah Abd^a, Kayser Aziz Ameen^a, Azher M. Abed^b, Ali Arif hatem^a, Kamaruzzaman Sopian^c

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.45

Abstract In a Fresnel-based Concentrated Photovoltaic system, multi junction solar cells suffer from increased PV temperature, resulting in a decrease its electrical efficiency. This study design to investigate the influence of using Water/Al₂O₃ Nanofluid as cooling fluid on heat transfer enhancement and top surface temperature for multi-junction solar cell in the Fresnel-based Concentrated Photovoltaic thermal CPVt System. The CFD simulation was conducted on mini-channel under the concentrated multi-junction solar cell with using water/Al₂O₃ Nanofluid and pure water as coolant fluids. The Reynolds number is in the range of 15000-30000 were examined. The average Nusselt numbers augmented through increasing Reynolds numbers. The… More >

Kai Zhu¹, Hao Chen^1,*, Shuang Wang^1,*, Chuan Yuan^1,2, Bin Cao³, Jun Ni¹, Lujiang Xu⁴, Anqing Zheng⁵, Arman Amani Babadi¹

Journal of Renewable Materials, Vol.11, No.6, pp. 2849-2864, 2023, DOI:10.32604/jrm.2023.026317

Abstract Microalgae biomass is an ideal precursor to prepare renewable carbon materials, which has broad application. The bioaccumulation efficiency (lipids, proteins, carbohydrates) and biomass productivity of microalgae are influenced by spectroscopy during the culture process. In this study, a bilayer plate-type photobioreactor was designed to cultivate Chlorella protothecoides with spectral selectivity by nanofluids. Compared to culture without spectral selectivity, the spectral selectivity of Ag/CoSO₄ nanofluids increased microalgae biomass by 5.76%, and the spectral selectivity of CoSO₄ solution increased by 17.14%. In addition, the spectral selectivity of Ag/CoSO₄ nanofluids was more conducive to the accumulation of nutrients (29.46% lipids, 50.66% proteins, and… More > Graphic Abstract

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 >

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 >

Ayad S. Abdallah^a,b,*, Nabil Jamil Yasin^a, Hani Aziz Ameen^a

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-7, 2022, DOI:10.5098/hmt.18.10

Abstract To reduce the energy consumption in air-conditioning systems without changing the required temperature level in the air-conditioned space, Heat Pipe Heat Exchanger (HPHE) has been experimentally used and tested. The heat pipe has been filled with working fluid by about 50% of the volume of the evaporator which represents the filling ratio. In this research, three mass concentration of nanoparticle from copper oxide (CuO), 1wt%, 3wt% and 5wt% have been used and studied. Additionally, its effect on the HPHE effectiveness and the heat recovery ratio at different inlet air temperatures, 30, 35, 40, 45, 50, and 55 °C, have been… More >

Zainab Kareem Ghoben^a,*,†, Ahmed Kadhim Hussein^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-11, 2022, DOI:10.5098/hmt.18.6

Abstract he numerical analysis of a V-shaped baffle effect on the natural convection inside a parallelogrammical cavity filled with two different water-based nanofluids (Al2O3 and Cu) were studied in this work. The enclosure walls were maintained at a constant hot and cold temperatures on the left and right walls sequentially. The horizontal walls were isolated, while the baffles located on the right wall and sharing the same cold temperature with it. The finite element method was used to derive and solve the governing equations. The flow and thermal fields computed for different arrangements of: the number of baffles inside the cavity… More >

Yun Hao^* , Shaohua Lv, Song Wu

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.3

Abstract Traditional methods of enhancing the thermal efficiency of heating furnaces in continuously producing oilfields, such as replacing existing units with more efficient units or renovating old furnaces, are highly inconvenient. This paper studied on the characteristics of nanofluids, a novel heat transfer medium with excellent heat transfer characteristics to enhance the thermal efficiency of heating furnaces. The stable nanofluids (Al₂O₃-H₂O, SiO₂- H₂O, and TiO₂-H₂O) were prepared by a two-step method and various chemical and physical treatments were carried out. Thermal conductivities of the nanofluids were measured using the transient hot-wire method. Based on the analysis, the most appropriate nanofluid (TiO₂-H₂O)… More >

P. Madhu Sravanthi^a,b, M. Radha Madhavi^a,*

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-9, 2022, DOI:10.5098/hmt.19.40

Abstract In this paper, reaction of magnetic field and activation energy is applied on nanoparticles and swimming gyrotactic microorganisms under the viscous dissipation is inspecting. The effect of thermophoresis and Brownian motion is also considered. The PDEs are naturalized into ODEs by using similarity transformations. To solving the PDEs by using RK-Fehlberg with shooting approach by MATLAB software. The effect of magnetic parameter, Schmidt number, Prandtl number, Brownian motion, thermophoresis, Peclet number, porosity parameter, on velocity, temperature, concentration, motile microorganism density portrait is in detailed it is discussed and the eventualities are demonstrated in graphs. The effects of these factors on… More >

Namphon Pipatpaiboon^a , Teerapat Chompookham^b, Sampan Rittidech^b, Yulong Ding^c, Thanya Parametthanuwat^d, Surachet Sichamnan^a,*

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-9, 2022, DOI:10.5098/hmt.19.24

Abstract When nanofluid (NF) is used as the working fluid in a rectangular two-phase closed thermosyphon (RTPCT), the formations and heat performance of two-phase flow patterns are explored qualitatively. Silver nanoparticles were mixed with deionized water at a concentration of 0.5 wt% in the NF. Nanoparticles improved the thermal contact surface area within the base flow, allowing the base fluid to boil quickly and easily. When the working fluid was boiled, NF also demonstrated high thermal conductivity capabilities, which diffused and moved along with the dual flow patterns. As a result, these qualities improved the RTPCT's efficiency. Considering the findings of… More >