Diego Angeli^a,*, Arturo Pagano^b, Mauro A. Corticelli^a, Alberto Fichera^b, Giovanni S. Barozzi^a

Frontiers in Heat and Mass Transfer, Vol.2, No.2, pp. 1-9, 2011, DOI:10.5098/hmt.v2.2.3003

Abstract A numerical analysis of transitional natural convection from a confined thermal source is presented. The system considered is an air-filled, square-sectioned 2D enclosure containing a horizontal heated cylinder. The resulting flow is investigated with respect to the variation of the Rayleigh number, for three values of the aspect ratio A. The first bifurcation of the low-Ra fixed-point solution is tracked for each A-value. Chaotic flow features are detailed for the case A = 2.5. The supercritical behaviour of the system is investigated using nonlinear analysis tools and phase-space representations, and the effect of the flow on heat transfer is discussed. More >

CH. Amanulla^a,b , N. Nagendra^a,1 , M. Surya Narayana Reddy^b , A. Subba Rao^a , O. Anwar Bég^c

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-13, 2017, DOI:10.5098/hmt.8.29

Abstract In this article, the heat, momentum and mass (species) transfer in external boundary layer flow of Casson nanofluid from an isothermal sphere surface is studied theoretically. The effects of Brownian motion and thermophoresis are incorporated in the model in the presence of both heat and nanoparticle mass transfer. The governing partial differential equations (PDEs) are transformed into highly nonlinear, coupled, multi-degree non-similar partial differential equations consisting of the momentum, energy and concentration equations via appropriate non-similarity transformations. These transformed conservation equations are solved subject to appropriate boundary conditions with a second order accurate finite difference method of the implicit type.… More >

Yashwant Singh^a , Rajesh Maithani^b , Sunil Kumar^a , Ehsan Gholamalizadeh^c , Anil Kumar^a,d,*

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-16, 2018, DOI:10.5098/hmt.11.33

Abstract Nanofluids play important roles in the heat transfer and flow characteristics in ribbed square channels. Systematic experiments are conducted to measure heat transfer enhancement and TiO₂-H₂O based nanofluid flow characteristics on a protruded with combined V-type ribbed square channel. Reynolds number studied in the channel range from 4000-18000. Investigational parameters of square channel contain, volume fraction range of 1.0- 4.0%, particle diameter range of 30nm-45nm, relative protruded rib height range of 0.10-0.25, ratio of protruded height to print diameter range of 0.8- 2.0, relative protruded rib pitch ratio range of 2.0-3.5 and angle of attack of 300 -750 respectively. Results… More >

Lohit Sharma^a , Sunil Kumar^a , Robin Thakur^a , Bhaskar Goel^a , Amar Raj Singh Suri^a , Sashank Thapa^a , Nitin Kumar^a , Rajesh Maithani^b , Anil Kumar^b

Frontiers in Heat and Mass Transfer, Vol.14, pp. 1-15, 2020, DOI:10.5098/hmt.14.30

Abstract This article presents an extensive review on exergy analysis of nanofluid flow through heat exchanger channels. The improvement of exergy efficiency of nanofluid flow through heat exchanger are determined by the net impact of the relative variations in the thermophysical properties of the nanoparticle which are sensitive towards numerous parameters including size and shape, material and concentration as well as base fluid thermal properties. Exergy efficiency of nanofluids flowing through heat exchanger is greater as compare to simple conventional fluids. The augmentation of exergy efficiency in the nanofluid flow through heat exchangers can be achieved by breaking laminar sub layer… 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 >

Olanrewaju M. Oyewola^a,b,*, Samuel I. Afolabi^b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.20

Abstract This paper investigates numerically the problem of convective heat transfer and entropy generation by two adiabatic obstacles positioned inside a square cavity heated at the left wall and cooled on the right wall while horizontal walls are adiabatic. The inclination angle of the cavity orientation investigated are 30, 60 and 90 degrees. Rayleigh numbers ranging from 103 to 106 were calculated for two vertical obstacles. The method of Galerkin finite element was employed to solve the conservation equations of mass, momentum and energy. The cavity is assumed to be filled with air with Prandtl number of 0.71. It was observed… More >

Mirmanto Mirmanto^a,*, Syahrul Syahrul^a, Agung Tri Wijayanta^b

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-5, 2023, DOI:10.5098/hmt.20.9

Abstract A study to examine the effect of evaporator diameters on the performances of a custom air-water generator had been conducted in naturally room air temperatures. Performances in this study consisted of fresh water production, coefficient of performance, and total heat transfer from the air. The freshwater was attained from the dew that dropped from the evaporator walls. It was from water vapour in the air that condensed due to the low temperature of the evaporator walls. The evaporator which had dimensions of 285 mm x 12.7 mm x 480 mm was placed in an open box (top and bottom). It… More >