水力驱动转子式能量回收装置启动特性研究

实现水力驱动运行对提升海水淡化能量回收装置控制灵活性和工作可靠性具有重要意义。基于FLUENT软件,建立了转子式能量回收装置水力驱动运行流固耦合模型,在操作压力6.0 MPa及高、低压入口流速5.0 m/s条件下,分析了装置启动运行时转速响应特性和高、低压流体流动速度变化规律。结果表明,转子转速呈先快速增长后趋于平稳的发展趋势,且在1.25 s的启动时间内,装置理论转速可达1 395 r/min;装置高压区和低压区内,端盘楔形结构对应的转子孔道内流体始终存在切向速度差,其是驱动装置水力转动的主要动力。

Startup Characteristics of Hydraulic-Drive Rotary Energy Recovery Device

Realizing the hydraulic-drive operating is of great importance for enhancing the controlling flexibility and working reliability of energy recovery device in seawater desalination process. Based on the FLUENT software, fluid-solid coupling model for hydraulic-drive energy recovery device was built in this paper. Under the operational pressure of 6.0 MPa and entrance velocity of 5.0 m/s for high and low pressure streams, characteristics of the device＇ s rotating speed and flow velocity at high and low pressure regions were studied and analyzed at the startup stage. Results show that the rotating speed increases rap- idly at the beginning and then tends to remain constant. The final steady rotating speed can be up to 1 395 r/min in 1.25 s of startup period. At high and low pressure regions, tangential velocity difference appears in fluid between the entrance and center of those rotor channels mantled by the end-cover wedge structure. The velocity difference is believed to be the main force that hydraulically drives the device.