Numerical Simulation Of The Flow Inside The Head Of Turbine

Industrial steam turbine is widely used in power plant, chemical industry and many other important fields. The performances of the industrial steam turbines have great influence on the national economy. Steam turbine driving furnace feed water pump of 600MW power plant is one of the key products in the industrial steam turbine market and there is a great demanding in the current market. The improvement of the design of the steam turbine may bring a great profit, economically, environmentally, or socially.To improve the performance of the steam turbine, it is crucial to understand the flow structure in the machine. Based on the computational fluid dynamics software, STAR-CD, a numerical analytic platform was developed in this paper, after a detailed discussion of the flow controlling equation, turbulence modeling, discretization of the governing equation, geometry modeling of the steam turbine, mesh generation, boundary condition, etc.. The numerical simulations of the flow in the head of the steam turbine were presented.Based on the careful analysis of the flow field, the key factors affecting the performance of the machine were discussed and various measures were proposed to improve the design of the steam turbine. Some modifications were made so as to improve the stabilization of the internal flow and the dynamic performance as well.Intensive researches were carried out on the blade profile modification with the Design3D, a module of NUMECA, in attempt to reduce the aerodynamic losses in the stator blades and rotor blades as well. Results indicate that tip convergent end wall techniques can effectively reduce the flow losses in the stator blade, and rotor blade can be effectively modified by a redesign of the blade profile. An overall efficiency increase of 1.57 percent was achieved with intensive numerical experiment.The research results presented in this thesis may provide some guideline for the design of the inflow turbine. The numerical analytic platform for the flow in the inflow turbine developed to be a powerful and practical tool in the design of the inflow turbine that can shorten the design cycle and cut the design cost effectively.