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Je-Chin Han^*, Akhilesh P. Rallabandi
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-21, 2010, DOI:10.5098/hmt.v1.1.3001
Abstract Film cooling is widely used to protect modern gas turbine blades and vanes from the ever increasing inlet temperatures. Film cooling involves a very complex turbulent flow-field, the characterization of which is necessary for reliable and economical design. Several experimental studies have focused on gas turbine blade, vane and end-wall film cooling over the past few decades. Measurements of heat transfer coefficients, film cooling effectiveness values and heat flux ratios using several different experimental methods have been reported. The emphasis of this current review is on the Pressure Sensitive Paint (PSP) mass transfer analogy to More >

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Chen Fang^*, Milnes David, Anita Rogacs, Kenneth Goodson
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-11, 2010, DOI:10.5098/hmt.v1.1.3002
Abstract Vapor-venting microchannel heat exchangers are promising because they address the problems of high pressure drop, flow instability, and local dryout that are common in conventional two-phase microchannel heat sinks. We present a 3D numerical simulation of the vapor-venting process in a rectangular microchannel bounded on one side by a hydrophobic porous membrane for phase-separation. The simulation is based on the volume of fluid (VOF) method together with models for interphase mass transfer and capillary force. Simulation shows the vapor-venting mechanism can effectively mitigate the vapor accumulation issue, reduce the pressure drop, and suppress the local More >

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Po Ting Lin, Hae Chang Gea, Yogesh Jaluria^*
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-20, 2010, DOI:10.5098/hmt.v1.1.3003
Abstract Thermal systems play significant roles in the engineering practice and our lives. To improve those thermal systems, it is necessary to model and optimize the design and the operating conditions. More importantly, the design uncertainties should be considered because the failures of the thermal systems may be very dangerous and produce large loss. This review paper focuses on a systematic strategy of modeling and optimizing of the thermal systems with the considerations of the design uncertainties. To demonstrate the proposed strategy, one of the complicated thermal systems, Chemical Vapor Deposition (CVD), is simulated, parametrically modeled,… More >

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Moran Wang^a, Bin-Yang Cao^b, Zeng-Yuan Guo^b,*
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-8, 2010, DOI:10.5098/hmt.v1.1.3004
Abstract The thermomass theory regards heat owning mass-energy duality, exhibiting energy-like features in conversion and mass-like features in transfer processes. The equivalent mass of thermal energy is determined by the mass-energy equivalence of Einstein, which therefore leads to the inertia of heat in transfer. In this work, we build up a thermomass gas model based on this theory to describe the fluid-flow-like heat conduction process in a medium. The equation of state and the governing equations for transport for the thermomass gas have been derived based on methodologies of the classical mechanics since the drift speed… More >

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Harumi Toriyama^*, Yutaka Asako
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-6, 2010, DOI:10.5098/hmt.v1.1.3005
Abstract Effects of a magnetic field on aeration through porous medium compost have been investigated numerically. Some composts yield heat over 60 degrees Celsius in fermentation process. That exothermic reaction produces a considerable amount of heat, which could be a potential heating source. Fermentation reaction requires aeration, sufficient supply of paramagnetic oxygen gas and exhaust of metabolized diamagnetic carbon dioxide gas. Continuous and forced air supply is more efficient rather than conventional manual turns or stirrings as aeration means. In magnetoaero-dynamics, the magnetizing force acting on a paramagnetic oxygen gas is applied for the enhancement of More >

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202

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Patrick H. Oosthuizen^*, Jane T. Paul
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-8, 2010, DOI:10.5098/hmt.v1.1.3006
Abstract Natural convective heat transfer from narrow vertical plates which have a uniform surface heat flux has studied. With a narrow plate the heat transfer rate is dependent on the flow near the vertical edges of the plate. The magnitude of the edge effects will depend on the conditions existing near the edges of the plate. Three situations have here been considered these being a heated plate imbedded in a large plane adiabatic surface, the surfaces of the heated plane and the adiabatic surface being in the same plane, a heated plate with plane adiabatic surfaces More >

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206

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R. J. Johnson^∗, R. Pitchumani^†
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-9, 2010, DOI:10.5098/hmt.v1.1.3007
Abstract Much research is currently being performed with carbon nanotube additives to neat resin systems to enhance properties such as thermal and electrical conductivity, strength, modulus and damping. Fabrication of parts based on carbon nanotube filled resin systems requires information on their cure kinetics and rheology, which has been relatively less studied so far. This work presents an extensive experimental study that systematically characterizes the cure kinetics and viscosity as a function of degree of cure and temperature of EPON 815C/EPICURE 3274 epoxy resin system laden with carbon nanotubes. Studies are conducted to determine the effects More >

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189

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Bengt Sundén^*, Jinliang Yuan
Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-20, 2010, DOI:10.5098/hmt.v1.1.3008
Abstract Depending on specific configuration and design, a variety of physical phenomena is present in fuel cells, e.g., multi-component gas flow, energy and mass transfer of chemical species in composite domains and sites. These physical phenomena are strongly affected by chemical/electrochemical reactions in nano-/micro-scale structured electrodes and electrolytes. Due to the electrochemical reactions, generation and consumption of chemical species together with electric current production take place at the active surfaces for all kinds of fuel cells. Furthermore, water management and twophase flow in proton exchange membrane fuel cells (PEMFCs) and internal reforming reactions of hydrocarbon fuels More >

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