P. V. Ramana, Arunn Narasimhan^*, Dhiman Chatterjee

Frontiers in Heat and Mass Transfer, Vol.3, No.2, pp. 1-6, 2012, DOI:10.5098/hmt.v3.2.3007

Abstract The present experimental study investigates the effect of tube-to-tube porous interconnectors on the pressure drop and heat transfer (Nu) of tube banks. A copper wire mesh porous medium connects successive tubes of the in-line and staggered arrangement of six rows of tubes. The tubes are subjected to constant and uniform heat flux and cooled by forced convection using water as a cooling fluid in the laminar flow range (100 < ReDuct < 625). The inline configuration with the tube-to-tube porous medium inter-connectors provides marginal enhancement of heat transfer and 12% reduction in the pressure drop More >

Nikola Stosic^**, Ian K. Smith, Ahmed Kovacevic

Frontiers in Heat and Mass Transfer, Vol.3, No.2, pp. 1-7, 2012, DOI:10.5098/hmt.v3.2.3003

Abstract Due to fast rotation of screw compressor rotors, temperature is uniform in the rotor cross section and temperature field is a function of the axial coordinate only. Apart of that the rotors in one cross section the rotors are simultaneously heated by hot gas on one side while cooled at another side by cold gas. As a result of identification of the main modes of heat transfer both in the rotors and between the rotors and their surroundings and the relative significance of each, a novel procedure is suggested to cool the rotors by injection… More >

Yunpeng Ren, J. K. Chen^*, Yuwen Zhang

Frontiers in Heat and Mass Transfer, Vol.3, No.2, pp. 1-7, 2012, DOI:10.5098/hmt.v3.2.3001

Abstract Heat transfer in a copper film irradiated by a femtosecond (fs) laser pulse train and by an integrated dual laser beam of a nanosecond pulse with a fspulse train was studied using the semi-classical two-temperature model. The critical point model with three Lorentzian terms was employed to characterize transient optical properties for the laser energy deposition. The effects of pulse number and separation time on the thermal response were investigated. The results showed that with the same total energy in a fs-pulse train, more pulses for shorter separation time, e.g., 1 ps, and fewer pulses More >

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 More >

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… More >

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 More >

Mohammad Izadifar^a,b,*, Xiongbiao Chen^a,b

Frontiers in Heat and Mass Transfer, Vol.3, No.4, pp. 1-7, 2012, DOI:10.5098/hmt.v3.4.3004

Abstract Heat can be potentially used for accelerating biodegradation of implanted tissue engineered scaffolds. Cyclic and continuous radio frequency (RF) heating was applied to implanted chitosan and alginate scaffolds at 4 applied voltages, 3 frequencies, and 2 thermally conditioning environments. A 3D finite element model was developed to simulate the RF treatment. A uniform RF heating was achieved at the scaffold top. For alginate, voltage was the only significant RF heating factor while both frequency and voltage significantly affected RF heating of chitosan. Less temperature gradient across the scaffold was achieved at a conditioning environment at More >

Soumei Baba^a,*, Nobuo Ohtani^a, Osamu Kawanami^b, Koichi Inoue^c, Haruhiko Ohta^a

Frontiers in Heat and Mass Transfer, Vol.3, No.4, pp. 1-8, 2012, DOI:10.5098/hmt.v3.4.3002

Abstract Effects of tube orientation on flow boiling heat transfer coefficients were investigated for FC72 flowing in single mini-tubes with tube diameters of 0.13 and 0.51 mm to define boundaries on a dominant force regime map. For the tube diameter of 0.51 mm, when mass velocity and vapor quality was varied, heat transfer coefficients were influenced by tube orientation at Froude number Fr < 4, while the effect of tube orientation on heat transfer coefficients disappears at Fr > 4. The results indicated that the boundary between the body force dominated and the inertia dominated regimes was… More >

Ze-Wei Zhang^*, Hui Wang^†, Qing-Hua Qin^∗,‡

Molecular & Cellular Biomechanics, Vol.9, No.1, pp. 31-54, 2012, DOI:10.3970/mcb.2012.009.031

Abstract This paper presents a hybrid finite element model for describing quantitatively the thermal responses of skin tissue under laser irradiation. The model is based on the boundary integral-based finite element method and the Pennes bioheat transfer equation. In this study, temporal discretization of the bioheat system is first performed and leads to the well-known modified Helmholtz equation. A radial basis function approach and the boundary integral based finite element method are employed to obtain particular and homogeneous solutions of the laser-tissue interaction problem. In the boundary integral based finite element formulation, two independent fields are More >

Zhiqiang Yang¹, Junzhi Cui², Yufeng Nie¹, Qiang Ma²

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.5, pp. 419-442, 2012, DOI:10.3970/cmes.2012.088.419

Abstract In this paper, a new second-order two-scale (SOTS) method is developed to predict heat transfer performances of periodic porous materials with interior surface radiation. Firstly, the second-order two-scale formulation for computing temperature field of the problem is given by means of construction way. Then, the error estimation of the second-order two-scale approximate solution is derived on some regularity hypothesis. Finally, the corresponding finite element algorithms are proposed and some numerical results are presented. They show that the SOTS method in this paper is feasible and valid for predicting the heat transfer performances of periodic porous More >