能量回收液力透平的研究现状及展望

能量回收液力透平技术的发展与应用对节能减排有重要意义.液力透平在石油、化肥等行业应用广泛,但存在设计理论与方法不完善、运行不稳定等问题,因此亟须开展相关研究.介绍了能量回收液力透平的工程应用、透平结构形式、能量回收装置形式,提出液力透平主要有反转泵式、冲击式、导叶式和专用液力透平,能量回收装置形式分为直驱式和辅助式.综述了近年来国内外取得的相关研究成果,探讨了能量回收液力透平的选型计算、优化设计、转速稳定性控制、力特性及结构强度、透平速度滑移现象.对能量回收液力透平技术研究的未来发展进行了展望,明确提出未来的重点方向是:采用新的理论与方法研制适用于各种特殊工况的液力透平,提高透平的效率;正确配置能量回收设备及系统参数,保证液力透平转速稳定性;在运行工况偏离设计点时,选择合理的调节方式充分回收余压能.

Status and prospect of study on energy recovery hydraulic turbines

Development and application of hydraulic turbine-based energy recovery technology have important significance in energy saving and emission reduction. Hydraulic turbines have been extensively used in petroleum, chemical and fertilizer industries, etc.; however, their design theory and method are imperfect, and their operation is subject to some instabilities as well, thus related studies on them are desirable. In this review, the application, structure and installation of energy recovery hydraulic turbine are described. It is shown that there are four sorts of structure for the turbine, namely pump as turbine, impulse turbine, guide-vane turbine and specialized turbine. The power transmission configuration of the turbine is in two modes, i.e. directly either a pump or a blower and indirectly driving a pump or a blower via a motor. Further, the achievements in the study on energy recovery hydraulic turbines obtained in China and aboard have been reviewed. The turbine selection, optimization design of runner, speed control, hydraulic thrust, structure strength and slip effect of velocity in the turbines are discussed. Finally, the development of hydraulic turbine-based energy recovery technology is prospected. The expected key study issues have been made clear, including:(1)to design and develop novel turbines that are suitable for various operating conditions and improve the total efficiency of the turbines,(2)to decide operation parameters of an energy recovery installation correctly to ensure the turbine operating stability,(3)to choose a feasible regulating method to recover the energy efficiently as the turbine is at its off-design point.