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Lucas Esclapez Valentina Ricchiuti John B. Bell Marcus S. Day 《Combustion Theory and Modelling》2020,24(2):194-220
We propose an algorithm for low Mach number reacting flows subjected to electric field that includes the chemical production and transport of charged species. This work is an extension of a multi-implicit spectral deferred correction (MISDC) algorithm designed to advance the conservation equations in time at scales associated with advective transport. The fast and nontrivial interactions of electrons with the electric field are treated implicitly using a Jacobian-Free Newton Krylov approach for which a preconditioning strategy is developed. Within the MISDC framework, this enables a close and stable coupling of diffusion, reactions and dielectric relaxation terms with advective transport and is shown to exhibit second-order convergence in space and time. The algorithm is then applied to a series of steady and unsteady problems to demonstrate its capability and stability. Although developed in a one-dimensional case, the algorithmic ingredients are carefully designed to be amenable to multi-dimensional applications. 相似文献
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Cam Anh Thieu Long Giang Bach Xuan Thang Cao 《Molecular Crystals and Liquid Crystals》2016,635(1):18-24
ABSTRACTThe effect of amounts (3, 5, 10, 20 wt%) of Bi2O3 on the sintering characteristics and porosity of Samaria-doped Ceria (SDC) based Lithium carbonate has been evaluated. The density had a maximum as high as 98.5% of theoretical density at 800°C with only 1wt%Li2CO3 and 3 wt%Bi2O3. The composite electrolytes showed high ion conductivity at evaluated temperatures. Composition and calcination temperature were found to affect the morphology and conductivity of the composite electrolytes greatly. The total conductivity closed to 3 orders of magnitude greater than pure SDC at operating temperature of 900°C and 3.5 orders of magnitude greater than pure SDC at operating temperature of 600°C. Especially, the best sample containing 3 wt% Bi2O3 sintered at 800°C for 2 h which had an ionic electrical conductivity of 0.17S cm?1. According to fuel cell performance, these composite electrolytes are chemically stable, which is an attractive prospect in intermediate temperature solid oxide fuel cell applications. 相似文献
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An innovative block copolymer capillary coating P(MAn-alt-St)127-b-PSt592, synthesized by maleic anhydride and styrene, was developed as a new kind of coating for capillary electrophoresis. The covalent bond coating was effectively applied in the separation of raw material (4-nitrobenzaldehyde) and production (2-[hydroxy(4-nitrophenyl)methyl]-cyclopent-2-enone) in a Baylis-Hillman reaction using ammonium acetate with 20% tetrahydrofuran (v/v) as the buffer solution. Electroosmotic flow measurement gave an instantly stable value after 70 times continued injection in 5 days and showed that P(MAn-alt-St)127-b-PSt592 coatings could suppress electroosmotic flow effectively compared with the bare capillary. The effects of tetrahydrofuran and the pH of buffer on the separation were investigated. The characteristics of the coatings to form micelles similar to surfactants were detected by atomic force microscopy. Moreover, the superiority of this coating was further applied in the separation of four aromatic amines. 相似文献
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采用硝酸盐-柠檬酸法合成出不同NiO含量的NiO/Ce_(0.8)Sm_(0.2)O_(1.9)(NiO/SDC)复合粉体,借助差热热重、XRD等对粉体的形成条件和相组成等进行了分析,并对粉体的比表面、粒度等进行了测定.由NiO/SDC粉体制备出固体氧化物燃料电池Ni/SDC金属陶瓷阳极材料,并对其微结构及相关性能进行了测试分析.结果表明:硝酸盐-柠檬酸法可以在较低的温度下合成出高比表面积的NiO/SDC粉体.制备的Ni/SDC阳极材料具有均匀细小的晶粒度和孔隙,以及高的电导率.1350 ℃烧结含55;NiO的NiO/SDC烧结体还原后所得Ni/SDC试样的孔隙率和电导率(700 ℃,H_2中)分别为38;和1825 S·m~(-1). 相似文献