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垂直轴风力机技术讲座(六)垂直轴风力机应用及其发展前景 总被引:1,自引:0,他引:1
1 垂直轴风力发电机的应用 以发电为目的垂直轴风力机主要有以下几种形式:大型并网垂直轴风力机;大型离网垂直轴风力机;小型并网垂直轴风力机;小型离网垂直轴风力机:互补型垂直轴风力发电机. 相似文献
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虽然水平轴风力发电机的技术已经发展的非常成熟,是世界上的主流风机,但在适应风机大型化、深海化的趋势方面,垂直轴风力发电机因其结构特点表现出一定优势。近年来,对于垂直轴风力机的研究日益增多,将两台相同的垂直轴风力机间隔一定距离置于一起即得到双转子垂直轴风力机。文章利用风机模拟与实际风场较接近的非定常风,通过物理模型试验对比了单转子垂直轴风力机和具有不同双转子间距的双转子垂直轴风力机在不同风速下同一转子的扭矩、转速与轴功率,证实了双转子垂直轴风力机的增益效果,并探讨了风速及两转子间距对风机性能及增益效果的影响。试验结果表明,风速越大、两转子间距越小,双转子垂直轴风力机的增益效果越显著。 相似文献
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采用计算流体力学方法(CFD)针对垂直轴风力发电机,开展简化的二维绕流特性研究。首先,基于开放型转子和增强型转子,研究网格节点数和壁面y+、计算时间步长和湍流模型等的变化对计算结果的影响,对计算模型和方法进行确认。随后,计算分析增强型垂直轴风力机与开放型垂直轴风力机的特性。结果表明,与开放性垂直轴风力发电机相比,增强型垂直轴风力发电机的功率系数和转矩系数有明显增加,且达到最大值的位置向叶尖速比增大的方向移动。然后对增强型垂直轴风力机发电机在不同来流风速下进行计算,发现增强型垂直轴风力发电机的转子转矩随来流风速增加,而转矩系数和功率系数与来流风速无关。最后,针对定子叶片在不同的方向开展计算研究。结果表明,定子叶片在不同方向时,增强型垂直轴风力机的转子转矩不同,且转矩到达峰值的位置也不同;在当前3个方向角中,叶片处于0°方向角时风力机具有最高的转矩系数,即具有最佳的功率系数。 相似文献
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The influence of changes in load conditions of the generator-transformer unit on the operating conditions of the 100% ground-fault protection of the generator stator winding based on the third-harmonic voltages was analyzed. The analyzed stator ground-fault protection system is by ratio of the voltages third harmonic in generator neutral and at the generator terminals. The third-harmonic voltages were determined on the base of the experimental tests (measurements) run in real conditions at changes in active and reactive load conditions of the generator. It was found that mainly the generator active load influences the voltage feeding the measuring element of ground-fault protection. Therefore, determining operating conditions of ground-fault protection the influence of the generator active and reactive load should be deeply considered. This can ensure the proper operation of the ground-fault protection based on the voltage third harmonics in the whole range of the changes in generator load. Considering the influence of changes in generator load on the third-harmonic voltages (feeding measuring element of the protection system) will allow eliminating irregular generator tripping as a result of unselective operation of these protections. 相似文献
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简要介绍了热电发电器的原理、特点、基本结构及其改进措施,总结了近年来国内外在热电发电器件研究方面的现状,最后展望了热电发电器的前景。 相似文献
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This paper briefly describes the various maintenance techniques carried out on the French PWR steam generators. The major applications have arisen due to the occurrence of primary side stress corrosion cracking problems at various transition regions of the Inconel 600 tubing. Reference is also made to several other applications not directly concerned with the tubing. 相似文献
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Kh. K. Aripov N. B. Alimova Kh. Kh. Bustanov E. V. Ob’edkov Sh. T. Toshmatov 《Applied Solar Energy》2010,46(1):46-48
The injection-voltaic electromotive force in multilayered semiconductor structures is investigated. It is shown that it is possible to amplify the signal in a device that uses the injection-voltaic operation mode of bipolar transistors with power supply from a silicon solar cell. 相似文献
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Experimental and numerical studies were carried out to evaluate the effect of vortex generator on a small cylindrical protrusion at Mach number 2.0. The experiments were performed using the supersonic blow down wind tunnel on different heights of cylindrical protrusion with vortex generator placed ahead of them. The upstream and downstream flow around the cylindrical protrusion is influenced by vortex generator as is observed using both visualization and pressure measurement techniques. Numerical studies using three dimensional steady implicit formulations with standard k-ω turbulence model was performed. Results obtained through the present computation are compared with the experimental results at Mach 2.0. Good agreements between computation and experimental results have been achieved. The results indicate that the aerodynamic drag acting on cylindrical protrusion can be reduced by adopting vortex generator. 相似文献
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根据某火力发电厂热力系统对水质的要求,在一级除盐系统设备、主要工艺等条件不变时,通过调整实验确定了再生剂的最佳用量,即最佳酸碱耗,较大地降低了发电成本。 相似文献
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In order to further studies on thermoelectric generation, an experimental thermoelectric generator unit incorporating the commercially available thermoelectric modules with the parallel-plate heat exchanger has been constructed. The experiments are carried out to examine the influences of the main operating conditions, the hot and cold fluid inlet temperatures, flow rates and the load resistance, on the power output and conversion efficiency. The two operation parameters such as the hot fluid inlet temperature and flow rate are found to significantly affect the maximum power output and conversion efficiency. A comparison of the experimental results with those from the previously published numerical model is also presented. The meaningful results obtained here may serve as a good guide for further improving the numerical model and conducting a system level optimization study in the next step. Also, the present study shows the promising potential of using this kind of thermoelectric generator for low-temperature waste heat recovery. 相似文献
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对我国内燃机车主发电机励磁系统采用的励磁机组励磁方式进行改进 ,利用三相全控桥对辅发发出的三相交流电进行整流给主发励磁的方式 ,省去了主发励磁机组 ,减少主发励磁系统的维护量 ,方便机车系统整体的布置 ,为内燃机车辅助系统的改造升级提供空间。 相似文献
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Yong Sung Kim Sylvie Lorente Adrian Bejan 《International Journal of Heat and Mass Transfer》2009,52(9-10):2362-2369
This paper shows that the architecture of a steam generator for a power plant can be deduced on the basis of the constructal law. According to constructal theory, the flow architecture emerges in time such that it provides progressively greater access to its currents. The circulation of water is driven by buoyancy in one large tube (the downcomer) and many parallel smaller tubes (the riser). The total flow volume is fixed. Two flow models are used: single phase liquid in the downcomer and riser, and liquid–vapor mixture in the riser tubes. Features that result from constructal design are: the tube diameters, the number of riser tubes, the water circulation rate, the rate of steam production, and how the flow architecture should change when the operating pressure and the size of the flow system change. 相似文献