Current Issue : April - June Volume : 2012 Issue Number : 2 Articles : 4 Articles
As a new technology, electric mobility has the potential to achieve a reduction in\r\nCO2 emissions and contribute to the transition from the current transportation system to a\r\nbetter one, environmentally speaking. The objective of the paper is to aid the necessary\r\ndecision-making for the adoption and development of electric vehicles in Spain, taking the\r\ntime horizon of 2020. This will be achieved by building a System Dynamics model for\r\nvarious scenarios that will be used for the analysis and comparison of various dynamic\r\nvariables, as well as to determine how, and to what extent, they will influence the number\r\nof electric vehicles that will run on Spanish roads in the coming years, focusing on the\r\ncost variable....
Nowadays, subjects such as eco-design requirements, product rating or code\r\ncompliance with regard to energy efficiency are expanding towards a pan-European level.\r\nThis leads to the necessity of defining zones within the European region, which share\r\ncommon climatic characteristics and will further facilitate the quick estimation of building\r\nenergy performance. Towards this direction stands the current paper; it presents an approach\r\nfor defining climatic zones in Europe on the basis of the amount of heating and cooling\r\ndegree days. It is applied for the climate classification of selected European cities and is\r\ncompared with the conventional scheme based solely on heating degree days. Since the\r\napproach is orientated mainly towards the assessment of building energy performance, its\r\noutcomes are evaluated with regard to the actual heating and cooling energy needs of a\r\nreference building unit with office use located in representative cities of the proposed\r\nclimatic zones and facing the four cardinal orientations. The classification of climatic\r\nzones on the basis of both heating and cooling degree days leads to more realistic results,\r\nsince nowadays cooling needs form a substantial part of the energy balance of the building,\r\nespecially in the Mediterranean regions....
A new type of brushless double rotor machine (BDRM) is proposed in this\r\npaper. The BDRM is an important component in compound-structure permanent-magnet\r\nsynchronous machine (CS-PMSM) systems, which are promising for power-split hybrid\r\nelectric vehicle (HEV) applications. The BDRM can realize the speed adjustment between\r\nclaw-pole rotor and permanent-magnet rotor without brushes and slip rings. The structural\r\ncharacteristics of the BDRM are described and its magnetic circuit model is built.\r\nReactance parameters of the BDRM are deduced by an analytical method. It is found that\r\nthe size characteristics of the BDRM are different from those of conventional machines.\r\nThe new sizing and torque equations are analyzed and the theoretical results are used in the\r\noptimization process. Studies of the analytical magnetic circuit and finite element method\r\n(FEM) model show that the BDRM tends to have high leakage flux and low power factor,\r\nand then the method to obtain high power factor is discussed. Furthermore, a practical\r\nmethodology of the BDRM design is developed, which includes an analytical tool, 2D field\r\ncalculation and performance evaluation by 3D field calculation. Finally, different\r\ntopologies of the BDRM are compared and an optimum prototype is designed....
An integrated full-field reservoir simulation study has been performed to\r\ndetermine the reservoir management and production strategies in a mature sandstone\r\nreservoir. The reservoir is a candidate for an enhanced oil recovery process or otherwise\r\nsubject to abandonment. Based on its charateristics, the reservoir was found to be most\r\nsuited for a surfactant/polymer (SP) flood. The study started with a large data gathering\r\nand the building of a full-field three-dimensional geological model. Subsequently, a full\r\nfield simulation model was built and used to history match the water flood. The history\r\nmatch of the water flood emphasizes the areas with remaining high oil saturations,\r\nestablishes the initial condition of the reservoir for an SP flood, and generates a forecast of\r\nreserves for continued water flood operations. A sector model was constructed from the\r\nfull field model and then used to study different design parameters to maximize the project\r\nprofitability from the SP flood. An economic model, based on the estimated recovery,\r\nresidual oil in-place, oil price, and operating costs, has been implemented in order to\r\noptimize the project profitability. The study resulted in the selection of surfactant and\r\npolymer concentrations and slug size that yielded the best economic returns when applied\r\nin this reservoir. The study shows that, in today�s oil prices, surfactant/polymer flood when\r\napplied in this reservoir has increased the ultimate oil recovery and provide a significant\r\nfinancial returns....
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