共查询到20条相似文献,搜索用时 109 毫秒
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农村水电站更新改造行业管理机制体系的研究 总被引:1,自引:1,他引:0
通过调研对行业管理实践进行了总结,采用经济机制设计理论对实践中的方法进行理论化和系统化提升,形成针对浙江省农村水电站更新改造的行业管理运作机制体系.结果表明,以机构和职能能力建设为基础、以安全生产管理机制为核心、以项目建设管理机制为监督、以行业协会管理机制为协调、结合国情和省情的该体系具有实际可操作性,是农村水电站更新改造领域中的创新. 相似文献
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风电的随机性和波动性增大了电网系统的调节压力,文章提出一种基于分层模型预测控制的源荷协调控制策略,该策略采用长、短时间尺度的多时间尺度滚动优化控制。长时间优化控制以最小弃风运行成本最优为目标,以长时间风电预测为状态变量,以常规电源功率、高载能负荷功率和风电出力为控制变量,优化求解计划基点。短时间滚动优化控制以风电实际出力与计划出力偏差最小为目标,以短时间风电预测出力为状态变量,以连续可调高载能负荷为控制变量,优化求解控制指令,对预测误差的影响做出修正。采用二次规划法对优化控制模型进行求解。最后以新疆某地区电网为例,验证了所提出控制策略的有效性和可行性。 相似文献
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在炼油加工过程中,加热炉是能耗大户.对新建炼厂,在设计阶段提高加热炉热效率,对节能减排有重要意义.在设计过程中,采取燃料气脱硫等措施以降低排烟温度、降低空气过刹系数和漏风量等措施以降低过剩空气量、优化设计加热炉衬里以降低散热损失、优化余热回收系统方案和控制方案以提高烟气余热利用率和操作稳定性、利用装置废热预热助燃空气,... 相似文献
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关于我国建立现代煤炭交易市场体系研究 总被引:2,自引:0,他引:2
本文分析了煤炭订货会的发展历史、现状和存在问题,提出了以改革订货会为着力点,建立以传统煤炭订货交易体系为基础,柜台交易市场和期货市场相结合的、多层次的现代煤炭交易市场体系的建议。 相似文献
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Solar multi-mode heating system based on latent heat thermal energy storage and its application 下载免费PDF全文
为克服太阳能间断性和不稳定性的缺点进而实现太阳能集热与采暖的能量供需调节和全天候连续供热,提出了基于相变储热的太阳能多模式采暖方法(太阳能集热直接采暖、太阳能集热采暖+相变储热、太阳能相变储热采暖),并在西藏林芝市某建筑搭建了太阳能与相变储热相结合的采暖系统,该系统可根据太阳能集热温度和外界供热需求实现太阳能多模式采暖的自动控制和自动运行。实验研究表明:在西藏地区采用真空管太阳能集热器可以和中低温相变储热器很好地结合,白天储热器在储热过程中平均储热功率为10.63 kW,储热量达到92.67 kW·h,相变平台明显;晚上储热器在放热过程中供热量达85.23 kW·h,放热功率和放热温度平稳,储放热效率达92%,其储热密度是传统水箱的3.6倍,可连续供热时间长达10 h,从而实现了基于相变储热的太阳能全天候连续供热,相关研究结果对我国西藏地区实施太阳能采暖具有一定的指导作用。 相似文献
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Review on storage materials and thermal performance enhancement techniques for high temperature phase change thermal storage systems 总被引:1,自引:0,他引:1
Designing a cost-effective phase change thermal storage system involves two challenging aspects: one is to select a suitable storage material and the other is to increase the heat transfer between the storage material and the heat transfer fluid as the performance of the system is limited by the poor thermal conductivity of the latent heat storage material. When used for storing energy in concentrated solar thermal power plants, the solar field operation temperature will determine the PCM melting temperature selection. This paper reviews concentrated solar thermal power plants that are currently operating and under construction. It also reviews phase change materials with melting temperatures above 300 °C, which potentially can be used as energy storage media in these plants. In addition, various techniques employed to enhance the thermal performance of high temperature phase change thermal storage systems have been reviewed and discussed. This review aims to provide the necessary information for further research in the development of cost-effective high temperature phase change thermal storage systems. 相似文献
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Solar air conditioning is an important approach to satisfy the high demand for cooling given the global energy situation. The application of phase-change materials (PCMs) in a thermal storage system is a way to address temporary power problems of solar air-conditioning systems. This paper reviews the selection, strengthening, and application of PCMs and containers in latent thermal storage system for solar air-conditioning systems. The optimization of PCM container geometry is summarized and analyzed. The hybrid enhancement methods for PCMs and containers and the cost assessment of latent thermal storage system are discussed. The more effective heat transfer enhancement using PCMs was found to mainly involve micro-nano additives. Combinations of fins and nanoadditives, nanoparticles, and metal foam are the main hybrid strengthening method. However, the thermal storage effect of hybrid strengthening is not necessarily better than single strengthening. At the same time, the latent thermal storage unit has less application in the field of solar air-conditioning systems, especially regarding heat recovery, because of its cost and thermal storage time. The integration of latent thermal storage units and solar air-conditioning components, economic analysis of improvement technology, and quantitative studies on hybrid improvement are potential research directions in the future. 相似文献
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The Solar Energy Research Group in the Universiti Kebangsaan Malaysia has been set-up more than two decades ago. One of the activities is in the field of solar thermal process, particularly in development of solar assisted drying systems. Solar drying systems technical development can proceed in two directions. Firstly simple, low power, short life, and comparatively low efficiency-drying system. Secondly, the development of high efficiency, high power, long life expensive solar drying system. The group has developed four solar assisted drying systems namely (a) the V-groove solar collector, (b) the double-pass solar collector with integrated storage system, (c) the solar assisted dehumidification system for medicinal herbs and (d) the photovoltaic thermal (PVT) collector system. The common problems associated with the intermittent nature of solar radiation and the low intensities of solar radiation in solar thermal systems can be remedied using these types of solar drying systems. These drying systems have the advantages of heat storage, auxiliary energy source, integrated structure control system and can be use for a wide range of agricultural produce. 相似文献
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在热力发电过程中,存在发电功率低、发电成本高以及工业余热直接被释放到外界。为了优化热力发电系统,采用回热循环、选取最佳回热系数提高系统的整体效率。依据工程热力学的第一、二定律等数学理论建立数学模型。通过Ebsilon软件平台建立了一个典型的槽式太阳能光热发电回热系统仿真模型,通过设定特定的参数进行模拟。结果表明:随着回热系数的增加,发电量逐步增大;储热系统良好的调节作用是发电量稳定、安全、具有持续性,夜晚期间发电量稳定在1600.43 W左右、系统的光热转换效率在12.77%左右。该仿真研究为工业应用提供相应的依据,有利于促进槽式太阳能热发电回热循环系统的研究及工程化应用。 相似文献
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Thermal energy storage improves the load stability and efficiency of solar thermal power plants by reducing fluctuations and intermittency inherent to solar radiation. This paper presents a numerical study on the transient response of packed bed latent heat thermal energy storage system in removing fluctuations in the heat transfer fluid (HTF) temperature during the charging and discharging period. The packed bed consisting of spherical shaped encapsulated phase change materials (PCMs) is integrated in an organic Rankine cycle-based solar thermal power plant for electricity generation. A comprehensive numerical model is developed using flow equations for HTF and two-temperature non-equilibrium energy equation for heat transfer, coupled with enthalpy method to account for phase change in PCM. Systematic parametric studies are performed to understand the effect of mass flow rate, inlet charging system, storage system dimension and encapsulation of the shell diameter on the dynamic behaviour of the storage system. The overall effectiveness and transient temperature difference in HTF temperature in a cycle are computed for different geometrical and operational parameters to evaluate the system performance. It is found that the ability of the latent heat thermal energy storage system to store and release energy is significantly improved by increasing mass flow rate and inlet charging temperature. The transient variation in the HTF temperature can be effectively reduced by decreasing porosity. 相似文献
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