为减小涡轮机动叶顶部间隙泄漏造成的气动损失、提高叶顶冷却效率,提出在凹槽叶顶离散排布小隔板迷宫.根据某涡轮机动叶结构,设计了迷宫叶顶气膜冷却效率试验台,通过稳态液晶技术测量了间隙叶高比分别为1.0%,2.0%,3.0%和吹风比分别为1.0,1.5,2.0时隔板迷宫叶顶和凹槽叶顶的气膜冷却效率.结果表明:2种叶顶结构的平均冷却效率均随着叶顶间隙高度的增加而减小;在某间隙高叶比和吹风比范围内,隔板迷宫叶顶冷却效率最多比凹槽叶顶冷却效率高出63%;隔板迷宫显著扩大了叶顶的冷却范围,提高了冷却效率,使冷却效率的分布更加均匀。

关键词：燃气轮机；动叶叶顶；迷宫结构；间隙高度；气膜冷却

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Because of its minor environmental impact, electricity generation using wind power is getting remarkable. The further growth of the wind industry depends on technological solutions to the challenges in production and construction of the turbines. Wind turbine tower vibrations, which limit power generation efficiency and cause fatigue problems with high maintenance costs, count as one of the main structural difficulties in the wind energy sector. To mitigate tower vibrations auxiliary measures are necessary. The effectiveness of tuned mass damper is verified by means of a numeric study on a 5 MW onshore reference wind turbine. Hereby, also seismic-induced vibrations and soil-structure interaction are considered. Acquired results show that tuned mass damper can effectively reduce resonant tower vibrations and improve the fatigue life of wind turbines. This chapter is also concerned with tuned liquid column damper and a semiactive application of it. Due to its geometric versatility and low prime costs, tuned liquid column dampers are a good alternative to other damping measures, in particular for slender structures like wind turbines.

关键词：结构控制；调谐质量阻尼器；调液阻尼器

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In this study, we have conducted modeling of the energy demands and supply systems of an actual small-scale housing complex and evaluated the effect of CGS installation from the standpoint of environmental and the economic aspects. Then, we have developed a new CGS operational algorithm that controlled the CGS generator by following the temperature of the heat storage medium in the storage tank and we have demonstrated the advantageous effects of this method. In addition, we have discussed the appropriate heat storage tank capacity for the proposed method.

关键词：能源管理系统；热电联产系统；设施规划

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介绍了适用于低品位能源的有机朗肯循环余热发电、卡琳娜循环余热发电、温差发电、热声发电4种热发电形式的原理和特点,分析了有机朗肯循环工质对系统性能的影响和热声发电系统的转换效率,指出太阳能的综合利用具有良好的发展前景.提出了可有效利用太阳能的太阳能电池余热方案,即光伏光热联合发电的有机朗肯循环系统,该系统的两相升压装置将太阳能电池的余热转化为液轮机的电力输出,实现了将太阳能转化为电能的过程,提高了太阳能的综合利用率。

关键词：低品位能源；发电系统；有机朗肯循环；有机工质；太阳能；光伏光热

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提出了一种新型增压富氧焚烧垃圾近零排放电站的设计概念,采用液态排渣增压垃圾焚烧锅炉,增加制氧装置与烟气压缩净化回收系统.以日焚烧1100t城市垃圾的汽轮机发电机组为例,计算了炉膛压力分别为0.5,1.0,1.5 MPa下发电机组的经济性,并与常压富氧焚烧技术进行对比.结果表明:由于锅炉炉膛压力增高,烟气中水蒸气的凝结热可用于加热汽轮机低温凝结水,减少汽轮机抽汽量,增加汽轮机发电功率,发电机组输出功率可达到25MW左右;空气分离制氧电耗约占发电量的34%,CO2压缩电耗占发电量的5%,低于常压富氧焚烧.综合考虑电站其他辅机电耗后,0.5~1.5 MPa炉膛压力下的增压富氧焚烧垃圾发电机组的净效率可提高9.31%~9.90%。

关键词：垃圾焚烧发电；增压富氧燃烧；近零排放；净效率

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Titanium dioxide has been used as the white pigment since the ancient times.95% of its current usage in industry involves paints, cosmetics, plastics, paper, and food. However, in near future the economic impact of titanium dioxide seems to be controlled by energy related applications mostly. Therefore, this chapter projects a brief outlook on the added value provided by the titanium dioxide structures in new and emerging technologies of the energy sector. The applications focused are: solar fuels, solar cells, fuel cells, Li ion batteries and solid state lighting. In those applications, TiO_2 standouts with its chemical and thermal stability, morphology variety, position of conduction and valance band energy levels, optical properties and cost.

关键词：二氧化钛；新兴能源技术；聚焦

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Asymptotic solution for the shear stress distributions and velocity profiles of steady electroosmotic (EO) and magnetohydrodynamic (MHD) flows are obtained in a parallel flat plate microchannel. A fully-developed flow is considered and the fluid obeys a constitutive relation based in a simplified Phan-Thien-Tanner model. The effect of the following dimensionless parameters on the fluid flow control is predicted: the viscoelastic parameter and the Hartmann number. The momentum equation, boundary conditions and the constitutive rheological model are combined to formulating a nonlinear differential equation to solve the shear stress, which is expanded in a regular expansion series in powers of small Hartmann numbers. This limit of small Hartmann numbers and low electrical conductivity in the buffer solution correspond to the range where the electric and magnetic effects can be used to move a charged solution in the flow control and sample handling in biomedical and chemical analysis.

关键词：电渗流；磁流体流动；微通道；粘弹性流体

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采用锅炉火用平衡数学模型,对大型循环流化床(CFB)锅炉的各项火用损失和火用效率进行了分析,并以某亚临界300MW机组CFB锅炉为对象,进行了实例计算,并对不同参数等级CFB锅炉进行了火用效率分析.结果表明:CFB锅炉的燃烧和传热损失之和占燃料化学火用的45%以上,是锅炉的主要损失;提高机组容量和蒸汽参数,可以提高炉水平吸热温度,从而有效降低锅炉传热火用损失;锅炉排烟火用损失率在1%左右,比排烟热损失率小很多;CFB锅炉的可燃气体未完全燃烧火用损失率、散热火用损失率均可忽略不计;固体未完全燃烧火用损失由于损失的是未燃尽碳的化学火用,其热能品位较高,因此应重点采取措施减小该项损失;CFB锅炉炉渣占煤中灰分比例较高,降低炉渣物理火用损失对于提高锅炉效率具有重要意义。

关键词：CFB锅炉；火用效率；火用损失；节能；锅炉效率；热能品位

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在自行搭建的冷态流化床实验台的基础上,分别利用Kolmogorov熵、关联维以及Lyapunov指数对气固流化床床内气泡运动的复杂性进行了混沌特性分析,从定性、定量两个方面分析了鼓泡床、节涌床、湍动床和快速流化床的流动特性.结果表明:在流化床风帽入口P0处所测得的压力信号能够传达与侧墙压力测点P1-P10相同的信息;流化床气固两相流动具有混沌特性;鼓泡床压力脉动信号的Kolmogorov熵为0.11~0.15,其混沌程度最大,而节涌床、湍动床和快速流化床的Kolmogorov熵分别在0.08~0.09,0.09~0.11和0.11~0.13之间,混沌特性较弱;利用Kolmogorov熵、关联维以及Lyapunov指数的理论方法能够很好地辨别流化床的流化状态,有助于理解流化床的流动机理。

关键词：流化床；气固两相流；压力脉动；混沌分析；Kolmogorov熵；关联维；Lyapunov指数

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Actually, variable speed wind turbines are continuously increasing their market share, since it is possible to track the changes in wind speed by adapting shaft speed, and thus maintaining optimal power generation. The more variable speed wind turbines are investigated, the more it becomes obvious that their behavior is significantly affected by the used control strategy. Typically, they use aerodynamic controls in combination with power electronics to regulate torque, speed, and power. The aerodynamic control systems, usually variable-pitch blades or trailing-edge devices, are expensive and complex, especially for larger turbines. This situation provides a motivation to consider alternative control approaches. This chapter deals, therefore, with high-order sliding mode control of doubly-fed induction generator-based wind turbines. This kind of control strategy presents attractive features such as chattering-free behavior (no extra mechanical stress), finite reaching time, and robustness with respect to external disturbances (grid faults) and unmodeled dynamics (generator and turbine). High-sliding mode control appropriateness will be highlighted in terms of sensorless control and enhanced fault-ride through capabilities. Simulations using the NREL FAST code will be shown for validation purposes.

关键词：风力发电机组；双馈感应发电机；高阶滑模

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