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991.
Application of the Box-Wilson experimental design method for the spherical oil agglomeration of coal
Yakup Cebeci 《Fuel》2006,85(3):289-297
In this study, the Box-Wilson statistical experimental design method was employed to evaluate the effects of important variables such as bridging liquid (oil) concentration, salt (CaCl2·2H2O) concentration and stirring speed on the agglomeration of bituminous coal. Response function coefficients were determined by the regression analysis of experimental data and the predictions were found to be in good agreement with the experimental results. The optimum kerosene concentration, CaCl2·2H2O concentration and stirring speed were determined as 30 wt%, 1 M and 1683 rpm, respectively, when considering combustible recovery and ash content.In addition, contact angle and solution surface tension measurements were carried out to evaluate of agglomeration success with the contact angle values and surface tension values. The surface tension of CaCl2 2H2O solutions and the average contact angle increased with increasing CaCl2·2H2O concentration. 相似文献
992.
993.
A computationally efficient algorithm for electromagnetic (EM)‐simulation‐driven design optimization of microwave structures is proposed. Our technique exploits variable‐fidelity EM simulations and the multilevel design approach where an approximate optimum of the lower accuracy but faster EM model of the structure under design is used as a starting point for optimizing a more accurate model. Several enhancements of the basic multifidelity method are introduced, including an efficient algorithm of optimizing EM models that is based on local response surface approximations, as well as automated adjustment of model fidelity. Convergence of the procedure to the optimum design is ensured by defaulting to the higher fidelity model whenever the prediction given by the lower fidelity fails to improve the design. Distribution of the computational effort between the models of different fidelity allows for making larger steps in the design space at a low cost, as well as substantial reduction of the number of high‐fidelity model evaluations, because the high‐fidelity model is only referred to in the last design stage. The article provides comprehensive numerical verification of our technique. Substantial computational savings are demonstrated in comparison to the benchmark methods: over 40% on average as compared to a basic version of the multifidelity optimization approach and over 95% as compared to direct optimization of the high‐fidelity model. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:281–288, 2014. 相似文献
994.
刘峰 《硫磷设计与粉体工程》2004,(5):15-18
贮仓是许多工业过程中的常用设备,起拱是贮仓使用时常出现的故障,如何解决起拱问题是贮仓设计的关键,除常采取增大仓壁倾角、设置破拱装置等方法外,设计成曲线贮仓也是行之有效的措施之一。分析了指数曲线贮仓的工作原理和特点,建立了仓壁指数曲线方程,阐述了设计步骤与注意事项,并举例说明。 相似文献
995.
《Advanced Engineering Informatics》2014,28(1):11-27
In this paper an evolutionary technique is proposed as a method for generating new design solutions with genotypes represented in the form of hierarchical hypergraphs. Such hypergraph-based evolutionary design requires the adaptation of traditional evolutionary operators like cross-over and mutation. This paper presents an attempt at defining modified cross-over and mutation operators that act on hierarchical hypergraphs. The application of the proposed transformations is illustrated on examples of designing floor layouts and furniture with the use of the evolutionary method. 相似文献
996.
AbstractThis article introduces a case study undertaken in the indigenous Penan community of Long Lamai, Upper Baram, Sarawak, Malaysia. In this community, there is concern about the negative image other cultural groups hold of the Penan. This case study explores co-design as a means to invite community members, together with a designer, to explore the identity that they would like to present to people outside the community. In preparing for an exhibition to challenge perceptions, it turned out to be important to embrace the culture of the community to facilitate self-expression, introducing new concepts such as technological interventions and design probes to stimulate reflection and creativity. However, it was indigenous material culture, when actively and encouragingly supported by the designer, that had a key role in developing the co-design and, with it, empathic understanding between designer and community. 相似文献
997.
Radial gas mixing in a fluidized bed was studied using response surface methodology (RSM), which enables effect examinations of parameters with a moderate number of experiments. All experiments were conducted in a 0.29-m ID fluidized-bed cold model. The gas dispersion process within the bed is described using the dispersed plug flow model. Pure carbon dioxide was used as the tracer gas, continuously injected into the center of the bed by a point source. The downstream radial tracer concentration profile was measured using a gas chromatograph.The radial gas dispersion coefficient, Dr, was well correlated with operating parameters and the particle and gas properties: (U−Umf)/Umf, Hs/db, φd, and Ar, with a determination coefficient R2 of 0.966. Effect test indicates that the dimensionless characteristic velocity, (U−Umf)/Umf, has the most significant influence on Dr, while the static bed height to bed diameter ratio, Hs/db, is less remarkable. The interactions of (U−Umf)/Umf with the distributor open-area ratio, φd, and with the Archimedes number, Ar, both play important roles. An evolutive response surface model was proposed to describe the radial gas mixing in the bubbling/slugging fluidization regimes. 相似文献
998.
999.
介绍冶炼烟气制本系统环保治理工程的工艺设计及生产运行情况。污水处理系统采用中和曝气加铁盐除砷工艺,引进了戈尔膜过滤器。尾气处理系统,采用石灰中和法,引进动波洗涤技术和关键设备。环保治理工程投产后,废气均达标排放。 相似文献
1000.
随着我国建筑总量和建筑能耗的快速增长,传统的供热方式已难以满足建筑供热的需求,而利用太阳能为建筑物供热,则可获得良好的节能和环保效益。就太阳能供热系统优化设计的相关问题进行了分析和研究,以期能为太阳能供热技术的推广和应用提供一定的理论依据。 相似文献