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Abstract: The numerical modeling of High Temperature Air Combustion (HTAC) could correctly predict the flame and emission characteristics so far, however, the precision is not satisfactory. In this paper, a parameter-modified Eddy-Break-Up (EBU) model with a three-step reaction scheme was used to simulate the HTAC process in a furnace of 2m ×2m×6.25m. Reynolds stress model (RSM) is used for the computational fluid dynamics (CFD) simulation. Comparison between experimental data from published papers, the original and modified EBU combustion models demonstrates that a smaller coefficient ‘A’ in the volumetric fuel consumption rate of the EBU model could improve the modelling precision. When ‘A’ is modified to be 1 other than its original value, 4, in the EBU model, the modeling could give improved results of the local distribution of CH4, temperature and NO emission. [Copyright &y& Elsevier]

Abstract: Distinguished from former literature which focuses on the static or balanced analysis, this paper established the timevarying parameters model based on state space model to find the dynamic relationship between China''s energy consumption and economic growth. After applying Chow test, unit root test and cointegration test, this paper estimated the parameters of state space model with Kalman Filter Algorithm, then found and analyzed their internal regularity. [Copyright &y& Elsevier]

Abstract: The waterway counts as a main and costly part of a hydro power project. Excavating tunnels for waterways by rock-blasting is a rapid method compared to utilizing tunnel boring machines (TBM). However the variation in cross-section geometry and surface roughness that arises in unlined rock-blasted tunnels results in a considerable increase in head loss due to friction. Several empirical formulas are available to calculate the total friction loss of an unlined hydro-power tunnel. However, the existing methods of documenting the final geometry, such as manual measuring, leveling and photographing, are time-consuming and introduce uncertainty.Recent development of terrestrial laser scanners (TLS) has increased the efficiency and accuracy of surface measurements. Improved documentation of the geometry of these hydraulic structures enables higher accuracy in hand-calculations, as well as in physical and numerical modeling.This paper investigates the application of TLS on existing rock-blasted hydro power tunnels. The measuring procedures and results from a test performed by a Topcon GLS-1500 scanner are presented. The result shows that three dimensional representations of the tunnel geometry can be derived in an efficient way with high accuracy. Hence, this method yields as an efficient method to document the geometry and estimate the roughness of an existing unlined hydro power tunnel. Parameters such as accuracy, resolution, time consume and costs are investigated in the current study. [Copyright &y& Elsevier]

Abstract: Double Blumlein generator is an excellent technique in generating high voltage short pulsed power with fast rise time signal. However properties of fixed pulse duration and polarity of Blumlein configuration limits the generator flexibility and efficiency. A modeling of double Blumlein with double switching configuration with controlled delay is proposed in this paper to solve the limitation problem. The circuit is modeled in PSpice environment and the result successfully showed double output pulse voltage of flat top square waveform with adjustable duration and polarity. [Copyright &y& Elsevier]

Abstract: In this paper, a practical method to design a robust controller for pressure of boiler in Mashhad Power plant using H∞ is proposed. To achieve a good performance of an industrial boiler in order to reduce fuel consumption rate and reaching higher efficiency, dynamic variables such as fuel flow, air flow and pressure of boiler must be controlled. However this dynamic model may associate with uncertainties. Uncertainties in mentioned model are caused by lack of knowledge about the dynamics of the system, pay load changes, and air flow. Thus, application of robust control methods for high precise control of pressure is inevitable. In the first step plant is identified by using experimental data by the mean of converting into a group of linear time invariant (LTI) uncertain plants. After representation of the uncertain dynamic system in general control configuration and modelling the parametric uncertainties, nominal performance, robust stability and robust performance against disturbances are analyzed by the concept of structured singular value μ. Then, using genetic algorithm an optimal controller is designed for tracking problem and disturbance rejection. This procedure gives a satisfactory controller at the presence of model perturbations. For more comparisons, quantitative feedback theory (QFT) as a well known robust control approach is also applied to the plant. Finally, nonlinear simulation has been carried out and two controllers are compared. Both optimal robust controllers guarantee robust performance of the system against the uncertainties and result in desired time responses of the output variables. By applying H∞ robust control, system tracks the desire reference inputs in a less time and with smoother time responses. [Copyright &y& Elsevier]

Abstract: Electrification level is a significant topic in energy and electric power planning. The paper sets up a LEAP model and designs three scenarios of economic growth of China, and simulates China''s electrification level by 2030. The results show that China''s electrification level has a larger increase potential in the mid-long term and rapid change of economic development pattern can help to increase the electrification level. By 2015, energy used for power generation will account for 43.3% of total primary energy consumption, while the ratio of electricity consumption to total final energy consumption will be about 23.1%; by 2020, the ratio of energy used for power generation to total primary energy consumption will increase to 44.9%, and the ratio of electricity consumption to final energy consumption will be about 25.6%; by 2030, the ratio of energy used for power generation to total primary energy consumption will be up to 47.2%, and the ratio of electricity consumption to total final energy consumption will reach about 28.9%. [Copyright &y& Elsevier]

Abstract: In order to forecast energy demand in China in the next 20 years, this paper firstly analyzes the current situation of China''s energy consumption, and then apply LEAP model to simulate primary energy and final energy demand in 2020, 2030 under different scenario composition about economic development, energy efficiency and energy structure. The results show that: the total primary energy demand will reach 4840-5070 Mtce in 2020, 5580-5870 Mtce in 2030; the share of coal in primary energy will decrease, and that of oil, natural gas and non-fossil energy sources will increase. For all the three economic growth scenarios, 40-45% carbon emission intensity reduction target can be realized. If non-fossil energy can be further developed, carbon emission intensity can reduce more than 45% by 2020. The goal of the 15% share of non-fuel energy in primary energy is difficult to realize, unless the most development potentials of hydro power, nuclear power and wind power can be reached. [Copyright &y& Elsevier]

Abstract: Based on the panel data of three industries in China, this paper calculates the energy rebound effect arising from energy efficiency improvement, by stripping the rebound of energy usage caused by industrial restructuring from model. Results indicate: the similarity between them demonstrating energy efficiency rebound effect as the main component of energy rebound effect; the delayed rebound peak of the secondary industry reflects its lagged respond to changes in energy efficiency; with regard to the peak value in 2009 when calculating the whole nation, author concerns it with the intensification in investment on basic industries and relaxation of restriction over high energy consumption enterprises; the relatively larger value of energy efficiency rebound in China can not be ignored by policy-makers [Copyright &y& Elsevier]

Abstract: This paper is concerned with the description and verification of an energy model of a building using the BSim software. The aim is to determine the effect of the basic heat gains on the energy consumption of a building. Simulations were performed on the basis of the actual hourly-interval climatic data over a whole year. It has been found, that the highest heat gain comes from solar radiation. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to analyze the current situation and environmental effects of household energy consumption in rural and urban areas. We suggest some measures on reducing emission and protecting environment from pollution. Based on questionnaires survey, we analyzed the quantity and structure of household energy consumption in urban and rural areas, and compared the environmental effects of energy use between urban and rural areas. We used SPIRPAT model to analyze the impact of population and income factors on the ecological footprint of energy use. The results show that there is an unobvious difference of per capita energy consumption between areas. But in terms of energy structure, urban households are dominated by the fossil energy, while rural households are dominated by both of biomass energy and fossil fuels. The emissions of rural households are much larger than those of urban households. However, the difference of social emissions from energy consumption between urban and rural households becomes little. Both population size and income factors have promoting effect on total energy and the ecological footprints of electricity and coal etc. in urban areas, so does on electricity and biomass in rural areas. [Copyright &y& Elsevier]