Zan Wu^a, Zhaozan Feng^b, Bengt Sundén^a,*, Lars Wadsö^c

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-10, 2014, DOI:10.5098/hmt.5.18

Abstract Thermal conductivity and rheology behavior of two aqueous nanofluids, i.e., alumina and multi-walled carbon nanotube (MWCNT) nanofluids, were experimentally investigated and compared with previous analytical models. Information about the possible agglomeration size and interfacial thermal resistance in the nanofluids were obtained and partially validated. By incorporating the effects of interfacial thermal resistance, a revised model was found to accurately reproduce the experimental data based on the agglomeration size extracted from the rheology analysis. In addition, the thermal conductivity change of the alumina/water nanofluid with elapsed time was investigated. Thermal conductivity measurements were also conducted for alumina/water and MWCNT/water nanofluid mixtures. More >

Junjie Chen^*, Longfei Yan, Wenya Song

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-6, 2014, DOI:10.5098/hmt.5.16

Abstract To understand the effect of different thermal conductivities on catalytic combustion characteristics, effect of thermal conductivity on micro-combustion characteristics of hydrogen-air mixtures in Pt/γ-Al₂O₃ catalytic micro-combustors were investigated numerically with detailed chemical kinetics mechanisms. Three kinds of wall materials (100, 7.5, and 0.5 W/m·K) were selected to investigate the effect of heat conduction on the catalytic combustion. The simulation results indicate that the catalytic reaction restrains the gas phase reaction in Pt/γ-Al₂O₃ catalytic micro-combustors. The gas phase reaction restrained by Pt/γ-Al₂O₃ catalysts is sensitive to thermal boundary condition at the wall. For most conditions, the gas phase reaction cannot be… More >

Majid Ahmed Mohammed¹, Abdullah Talab Derea², Mohammed Yaseen Lafta³, Obed Majeed Ali¹, Omar Rafae Alomar^4,*

Frontiers in Heat and Mass Transfer, Vol.21, pp. 215-226, 2023, DOI:10.32604/fhmt.2023.041668

Abstract It is common knowledge that phase-change materials are used for the purpose of thermal storage because of the characteristics that are exclusive to these materials and not found in others. These characteristics include a large capacity for absorbing heat and a large capacity for releasing heat when the phase changes; however, these materials have a low thermal conductivity. This paper presents the results of an experimental study that investigated the impact that nanoparticles of copper oxide had on reducing the temperature of solar panels. The phase change substance that was used was determined to be beeswax. The impact of adding… More >

Junjie Chen^*, Xuhui Gao, Deguang Xu

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-13, 2015, DOI:10.5098/hmt.6.10

Abstract Effect of wall thermal conductivity on hydrogen self-ignition and hydrogen-assisted ignition of propane-air mixtures in different feeding modes from ambient cold-start conditions were investigated numerically with chemical kinetic model in Pt/γ-Al2O3 catalytic micro-combustors. For the steady and transient state, effect of wall thermal conductivity on self-ignition characteristics of lean hydrogen-air mixtures was presented, and hydrogenassisted combustion of propane-air mixtures was investigated numerically in the co-feed mode and the sequential feed mode. The computational results indicate the large thermal inertia of the micro-combustor solid structure leads to slow temperature dynamics, and transient response is dominated by the thermal inertia. The heat… More >

B. Venkateswarlu^a, P.V. Satya Narayana^b,*

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-9, 2016, DOI:10.5098/hmt.7.16

Abstract This paper studies the Soret and Dufour effects on MHD flow of a Casson fluid past a stretching sheet in the presence of chemical reaction, viscous dissipation and variable thermal conductivity. The fluid is taken to be electrically conducting and the flow is induced by a stretching surface. The governing partial differential equations are transformed into non-linear ordinary differential equations using similarity transformations. The resulting equations are then solved numerically by shooting method. The impact of various stimulating parameters on the flow, heat and mass transfer characteristics are analyzed and discussed in detail through graphs. It is observed that the… More >

Odelu Ojjela^*, K. Pravin Kashyap, N. Naresh Kuma, Samir Kumar Das

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-9, 2016, DOI:10.5098/hmt.7.32

Abstract This article presents an unsteady incompressible Upper Convected Maxwell (UCM) fluid flow with temperature dependent thermal conductivity between parallel porous plates which are maintained at different temperatures varying periodically with time. Assume that there is a periodic suction and injection at the upper and lower plates respectively. The governing partial differential equations are reduced to non linear ordinary differential equations by using similarity transformations and the solution is obtained using differential transform method. The effects of various fluid and geometric parameters on the velocity components, temperature distribution and skin friction are discussed in detail through graphs. More >

Junpeng Lyu¹, Hai Mei^1,2, Liping Zu¹, Lisheng Liu^1,2,*, Liangliang Chu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 391-410, 2024, DOI:10.32604/cmes.2023.030614

Abstract This article proposes a modeling method for C/C-ZrC composite materials. According to the superposition of Gaussian random field, the original gray model is obtained, and the threshold segmentation method is used to generate the C-ZrC inclusion model. Finally, the fiber structure is added to construct the microstructure of the three-phase plain weave composite. The reconstructed inclusions can meet the randomness of the shape and have a uniform distribution. Using an algorithm based on asymptotic homogenization and finite element method, the equivalent thermal conductivity prediction of the microstructure finite element model was carried out, and the influence of component volume fraction… More >

Jakkid Sanetuntikul¹, Borwon Narupai², Nawadon Petchwattana^3,*

Journal of Renewable Materials, Vol.11, No.9, pp. 3567-3582, 2023, DOI:10.32604/jrm.2023.029308

Abstract Wastes from polypropylene (PP) packages are accumulating every year because it is one of the most widely consumed and short lifecycle products. This paper aims to develop low thermal conductive and fire-retardant materials from post-consumer PP (pPP) packages. Ammonium polyphosphate (APP) and hollow glass microsphere (HGM) were further added to improve the fire retardancy and thermal conductivity of pPP. The influence of APP and HGM on the mechanical and thermal properties, fire retardancy and thermal conductivity of pPP were investigated and compared with that of virgin PP (vPP). HGM was constantly added at 5 wt% while the content of APP… More > Graphic Abstract

Jadav Konch^*, G. C. Hazarika

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-10, 2017, DOI:10.5098/hmt.8.39

Abstract This paper investigates momentum, heat and mass transfer characteristics of a hydromagnetic Newtonian dusty fluid flow due to a rotating disk with radiation and viscous dissipation. The main objective of this paper is to study effects of temperature dependent viscosity and thermal conductivity on flow, temperature and species concentration. Radiation and viscous dissipation effects are also taken into account. Saffman model for dusty fluid is considered for the problem. The partial differential equations governing the flow are converted into ordinary differential equations employing similarity transformations. The resulting highly nonlinear coupled ordinary differential equations are solved numerically using shooting technique with… More >

Rachid Chadouli^a,b,*, Frédéric Lebon^a, Iulian Rosu^a , Mohammed Makhlouf^b

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-6, 2017, DOI:10.5098/hmt.8.30

Abstract In this paper, a numerical model investigating the impact of gasket thermal quality on the reduction in the thermal contact resistance (TCR) between two solids is presented and validated analytically. The model proposed is a 2D steady state model. The thermal conductivity of the solid materials ranges from 20 to 390 W/m·K, and the gasket thermal conductivity ranges from 0.16W/m·K (TC of rubber) to and 5W/m·K (TC of thermal paste). As expected, the results obtained clearly confirm that the gasket significantly improves the heat transfer between two solids in contact, and in particular that the TCR is decreased with increasing… More >