低温热源有机工质带叶片盘式透平设计及性能分析  

Design and Performance Analysis of Blade Disc Turbine in Low-grade Heat Source ORC System

作　　者：陈曦[1] 张燕平[1] CHEN Xi;ZHANG Yanping(Huazhong University of Science and Technology, Wuhan 430074, Hubei Province, China)

机构地区：[1]华中科技大学

出　　处：《发电技术》2019年第3期230-238,共9页Power Generation Technology

基　　金：国家重点基础研究发展计划项目(2015CB251504)~~

摘　　要：Tesla盘式透平是一种以流体边界层摩擦力带动转子旋转的非传统透平,具有结构简单、成本低廉、工质适应性好等优点,尤其适用于低品位热源余热回收系统。但由于其特有的做功方式,盘式透平的运行转矩与效率均远低于常规透平形式,这也是制约其商业应用的主要因素。在传统盘式透平的相邻盘片间增加导流叶片,并针对增加叶片后的透平结构进行了数学建模以及计算流体力学(computational fluid dynamics,CFD)验证。CFD验证表明,所建立的数学模型能够计算流体通道内的流体速度场、压力场分布,并能够预测透平效率在不同工况下的变化趋势。针对余热回收有机朗肯循环(organicrankine cycle,ORC)系统,利用所建立的数学模型,使用不同有机工质进行计算并进行对比。结果表明,在使用不同种类工质做功时,增加叶片均可以大幅提升盘式透平转矩与效率。Tesla disc turbine is a kind of unconventional turbine utilizing viscous force in the boundary layer to drive the rotor. Due to the simple structure and low cost as well as the good adaptability to the working fluids, Tesla disc turbine is especially adaptable to the low-grade heat source recovery system. But the unique working principle results in the low operation torque and low efficiency comparing with the common forms of turbines, thus the commercial application of disc turbine is limited. The blades were added between adjacent discs and a mathematcial model for the new turbine structure was formulated. Computational fluid dynamics (CFD) verified that the present mathematical model could calculate the velocity and pressure distribution of the working fluid in the flow field and could predict the efficiency variation trend under different working conditions. Utilizing the present mathematical model, calculations and comparisons were made aiming at low-grade heat recovery organic rankine cycle (ORC) system using different working fluids. The results show that, with different working fluids, adding blades between discs in Tesla disc turbine could significantly improve the operation torque and turbine efficiency.

关 键 词：发电 余热回收 盘式透平 数学模型 计算流体力学 有机朗肯循环 

分 类 号：TM61[电气工程—电力系统及自动化]