Search Results - subject:"Conductivity"

Numerical estimation of the effective electrical conductivity in carbon paper diffusion media

Zamel, Nada; Li, Xianguo; Shen, Jun - In: Applied Energy 93 (2012) C, pp. 39-44

directional dependent effective electrical conductivity of the layer for various porosity values. The distribution of the fibers … conductivity in this direction. This finding is in agreement with measured experimental data. Further, using the numerical results … of this study, two mathematical expressions were proposed for the calculation of the effective electrical conductivity of …

Persistent link: https://www.econbiz.de/10010572003

Effects of anisotropic permeability and electrical conductivity of gas diffusion layers on the performance of proton exchange membrane fuel cells

Ismail, M.S.; Hughes, K.J.; Ingham, D.B.; Ma, L.; … - In: Applied Energy 95 (2012) C, pp. 50-63

electrical conductivity of gas diffusion layers (GDLs). For a realistic range of transport properties being investigated, the … fuel cell performance was found to be very sensitive to the electrical conductivity but almost insensitive to the gas …-plane conductivity is maintained constant for all the cases investigated, for a realistic range of the in-plane electrical conductivity …

Persistent link: https://www.econbiz.de/10010572032

Modeling for conjunctive use irrigation planning in sodic groundwater areas

Kaledhonkar, M.J.; Sharma, D.R.; Tyagi, N.K.; Kumar, Ashwani - In: Agricultural Water Management 107 (2012) C, pp. 14-22

that vary with respect to soil CEC (Cation Exchange Capacity) and Ks (Saturated Hydraulic Conductivity) were considered in …

Persistent link: https://www.econbiz.de/10010576904

Application of nanofluids in heat exchangers: A review

Huminic, Gabriela; Huminic, Angel - In: Renewable and Sustainable Energy Reviews 16 (2012) 8, pp. 5625-5638

experimental results for the effective thermal conductivity, viscosity and the Nusselt number reported by several authors. The …

Persistent link: https://www.econbiz.de/10010580690

Results of experimental investigations on the heat conductivity of nanofluids based on diathermic oil for high temperature applications

Colangelo, Gianpiero; Favale, Ernani; de Risi, Arturo; … - In: Applied Energy 97 (2012) C, pp. 828-833

The work reported in this paper shows the experimental results from a study on diathermic oil based nanofluids. Diathermic oil finds application in renewable energy, cogeneration and cooling systems. For example, it is used in solar thermodynamic or biomass plants, where high efficiency, compact...

Persistent link: https://www.econbiz.de/10010702618

Transient behavior of proton exchange membrane fuel cell under non-isothermal condition

Hwang, Sang Soon; Lee, Pil Hyong; Jo, Soon Hye; Cha, … - In: Renewable Energy 42 (2012) C, pp. 54-59

steady state value as time is elapsed. Ion conductivity is the highest at the time of the load change and then reach to the … rapid as that in the voltage. Furthermore the lag in heat transfer through the reaction heat and higher ion conductivity at … density decreases as the heat transfer increases temperature, which gradually leads to low ion conductivity. …

Persistent link: https://www.econbiz.de/10011045162

Numerical sensitivity study of thermal response tests

Wagner, Valentin; Bayer, Peter; Kübert, Markus; Blum, … - In: Renewable Energy 41 (2012) C, pp. 245-253

Thermal conductivity and thermal borehole resistance are basic parameters for the technical and sustainable design of … conductivity and thermal borehole resistance. In order to examine primary effects in more detail, a sensitivity study based on … have minor effects (less than 10%) on the effective thermal conductivity and the determined borehole resistance. Constant …

Persistent link: https://www.econbiz.de/10011045248

Analysis of single-ring infiltrometer data for soil hydraulic properties estimation: Comparison of BEST and Wu methods

Xu, X.; Lewis, C.; Liu, W.; Albertson, J.D.; Kiely, G. - In: Agricultural Water Management 107 (2012) C, pp. 34-41

conductivity (Ks) and the water retention parameter (α). These were: (1) original BEST (Beerkan Estimates of Soil Transfer …

Persistent link: https://www.econbiz.de/10011047777

Detecting soil salinity changes in irrigated Vertisols by electrical resistivity prospection during a desalinisation experiment

Adam, I.; Michot, D.; Guero, Y.; Soubega, B.; Moussa, I.; … - In: Agricultural Water Management 109 (2012) C, pp. 1-10

cm) and were transformed into the inverse apparent electrical conductivity (ECa), (ii) soil samples were extracted from … ones. Mean electrical conductivity of 1:5 aqueous extract of soil samples (EC) decreased from initial values of 2.0, 2 …

Persistent link: https://www.econbiz.de/10011047827

Estimation of geological formation thermal conductivity by using stochastic approximation method based on well-log temperature data

Cheng, Wen-Long; Huang, Yong-Hua; Liu, Na; Ma, Ran - In: Energy 38 (2012) 1, pp. 21-30

Thermal conductivity is a key parameter for evaluating wellbore heat losses which plays an important role in … presented. The proposed method was able to estimate the thermal conductivity and the volumetric heat capacity of geological … results of which shown that the thermal conductivity and the volumetric heat capacity could be obtained with the relative …

Persistent link: https://www.econbiz.de/10011055373