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Alexandre Vaudrey^a,*, Philippe Baucour^b, François Lanzetta^b, Raynal Glises^b
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-8, 2012, DOI:10.5098/hmt.v3.3.3001
Abstract Producing electrical work in consuming chemical energy, the fuel cell (FC) is forced by the 2^nd law to reject heat to its surrounding. However, as it occurs for any other type of engine, this thermal energy cannot be exchanged in an isothermal way in finite time or through finite areas. As it was already done for various types of systems, including chemical engines, the fuel cell is here studied within the finite time thermodynamics framework. An endoreversible fuel cell is then defined, internally reversible but producing entropy during heat exchanges with its ambiance. Considering usual H₂/O₂ and H₂/air chemical reactions… More >

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Md. Farhad Ismail^a,*, M.A.I. Rashid^b , M. Mahbub^b
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-8, 2012, DOI:10.5098/hmt.v3.3.3002
Abstract Carbon nanotube (CNT) has been proven to be an effective material for the thermal management of MEMS-based devices due to its superior thermal conductivity. At the same time, micro-channel heat-sinks are widely used in electronic products as a high performance heat transfer device because of its simple construction, easy fabrication process and effective heat removal capability. A numerical study has been carried out to investigate the thermal-fluid characteristics of the aligned and staggered MWCNT (multi walled CNT) based micro pin fins having 650 µm long with hydraulic diameter of ~130 µm. Average heat transfer coefficients have been obtained for effective… More >

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Keyong Cheng^a,b,*, Chunzi Zhang^c, Wei Chen^a,b, Shiqiang Liang^a,†, Yongxian Guo^a,d, Xiulan Huai^a
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-6, 2012, DOI:10.5098/hmt.v3.3.3003
Abstract A film cooling method with chemical heat sink for gas turbine blades is proposed. In this method, an endothermic reaction of cooling stream occurs due to the heating from the mainstream, which leads to an improvement of film cooling effectiveness. The proposed method at different blowing ratios are computed and compared with the conventional one. The simulation result shows that due to the exsitence of the chemical heat sink the proposed method can enhance film cooling effectiveness not only in the streamwise direction, but also in the spanwise direction. More >

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Pranab Kumar Mondal^*, Sanchayan Mukherjee
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-6, 2012, DOI:10.5098/hmt.v3.3.3004
Abstract The present paper deals with the analytical investigation for the limiting value of Nusselt number, including the effect of viscous dissipation on heat transfer for a laminar shear driven flow between two infinite parallel plates, where the bottom plate is fixed and the top plate is moving in an axial direction at a constant speed. The study concentrates on hydro-dynamically fully developed flow of a Newtonian fluid of constant properties without considering the axial conduction in the fluid. To investigate the effect of viscous dissipation on heat transfer by defining the limiting Nusselt number, plates are kept at constant equal… More >

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Mohammad Izadifar^a,b,* , Jane Alcorn^c
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-7, 2012, DOI:10.5098/hmt.v3.3.3005
Abstract Applying local volume averaging method a mathematical model including liver porosity, tortuosity, permeability, unbound drug fraction, drugplasma diffusivity, axial/radial dispersion and hepatocellular metabolism parameters was developed for hepatic drug elimination. The model was numerically solved using implicit finite difference method to describe drug concentration gradient with time across the liver. Statistically validated by observations and other models, the model suggested axial dispersion as a significant variable in drug distribution across the liver. Sensitivity analyses revealed that lower liver porosity resulted in faster drug distribution across the liver, and bioavailability was sensitive to the interaction between unbound fraction and intrinsic clearance. More >

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Arafat A. Bhuiyan^a,1, A. K. M. Sadrul Islam^a, M. Ruhul Amin^b
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-9, 2012, DOI:10.5098/hmt.v3.3.3006
Abstract This numerical analysis presents the airside performance of a wavy fin-and-tube heat exchanger having 4 row configurations considering steady, incompressible and 3D flow using Commercial CFD Code ANSYS CFX 12.0. Results are presented in the form of friction factor (f), Colburn factor (j) and efficiency index (j/f). The numerical procedure has been validated by comparison with published numerical and experimental results and good agreement has been observed. A series of numerical calculations have been carried out in order to analyze the influence of various geometric characteristics on different fields as well as on the heat transfer and pressure drop and… More >

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Ahmad Najjaran¹, Ali R. Tahavvor, Abdolkarim Najjaran, Mohammad A. Ahmadfard
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-6, 2012, DOI:10.5098/hmt.v3.3.3007
Abstract In this paper, external radiation heat transfer coefficient and flux of a standing human body model are calculated for different emissivity coefficients and various temperature differences. To do this, a standing human body sample is designed in such a way that hands and feet are totally open and stretched. Soles are in contact with the ground and so do not have heat transfer. The results are extracted by weighted average method. Despite the existence of the air around the body in reality, the convection heat transfer of human body with the surrounding air is neglected in order to prevent errors… More >

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Milind S. Patil^a,*, Ramchandra S. Jahagirdar^b, Eknath R. Deore^a,†
Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-5, 2012, DOI:10.5098/hmt.v3.3.3008
Abstract Convection heat loss inevitably occurs in receivers of high concentrating solar concentrators. All the concentrators are need to be tack during the operation and hence the position of the receiver is changing continually. The angle of the receiver axis will then play an important role in the heat loss. Few researches were reported for the hemispherical cavity receivers numerically. The paper presented here is an experimental investigation natural convection heat loss from hemispherical cavity receiver. Cavity receiver of diameter 540 mm was tested. It is observed that the heat loss was minimum for 90° and maximum for 0°. More >

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