Power Generation Technology ›› 2019, Vol. 40 ›› Issue (1): 56-60.DOI: 10.12096/j.2096-4528.pgt.18222

• Power Generation and Environmental Protection • Previous Articles     Next Articles

Study on Installing Deflector in Exhaust Hood of Steam Turbine Based on Quadratic Regressive Orthogonal Experiment

Lihua CAO1(),Kai ZHOU2,Heyong SI1   

  1. 1 School of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, Jilin Province, China
    2 Harbin Turbine Company Limited, Harbin 150040, Heilongjiang Province, China
  • Received:2018-11-05 Published:2019-02-28 Online:2019-02-26
  • Supported by:
    the National Key R & D Plan(2017YFB0902100)

Abstract:

A combined numerical simulation is conducted to couple fluid flow between exhaust hood and last-stage blades of a 600 MW steam turbine using the computational fluid dynamics software CFX. Based on quadratic orthogonal regression design, the flow guide device at the top of the exhaust hood is installed. The regression orthogonal equation between the installation parameters of the guide plate and the coefficient of static pressure recovery is obtained. The equation is remarkably unlost with nonlinear relation and there is no influence among the three factors. The optimal solution of the regression equation is solved. The channel vortex is broken and the aerodynamic performance of the exhaust hood is improved obviously after the diversion plate is installed. The static pressure recovery coefficient of exhaust hood outlet is increased by 3.008%, the total pressure loss coefficient is reduced by 5.789% and the standard deviation of the outlet is reduced by 3.043. The static pressure recovery coefficient of exhaust hood outlet under different loads after the optimization is always higher than that before the optimization.

Key words: steam turbine, exhaust hood, flow guide device, quadratic regressive orthogonal experiment, aerodynamic performance