Título del libro: Geothermal Energy, Technology And Geology
Título del capítulo: Analysis and control of erosion in geothermal turbines
RAFAEL CAMPOS AMEZCUA;
Autores externos:
Idioma:
Inglés
Año de publicación:
2012
Palabras clave:
Blade tenon; Erosion; Geothermal turbines; Labyrinth seal; Numerical simulation; Rotor disc; Rotor end seal
Resumen:
In geothermal turbines, because of high steam contamination, the steam path elements can be subjected to impact damage from small solid particles and water droplets which can produce erosion by the continuous hitting to the solid elements surfaces. A significant erosion of solid surfaces can cause a structural problem and also a degradation of the turbine efficiency. This work presents the analysis of solid particle erosion of different elements of geothermal turbines using Computational Fluid Dynamics tool (CFD). These key steam path elements of turbines have a sharp erosion problem that threatens the reliable operation of the turbines, availability and performance. The numerical simulations were carried out using commercial codes based on a cellcentered finite-volume method. The analysis consists of application of the discrete phase model for modeling the solid particles flow, and the Eulerian conservation equations to the continuous phase. The study was based upon a renormalization group theory, RNG ?-? turbulence model and Reynolds Stress Model. The numerical modeling includes the fluid flow analysis through two geothermal turbines of 25 MW and 110 MW, and the erosion study of different elements of these turbines, such as low pressure end gland seal, fourth stage rotor disc, rotor labyrinth seal, and last stage blade tenon. The investigation permits evaluate the erosion damages on turbines component which depend on a number of parameters, such as particle size, angle of impingement, the number and hardness of particles, particle velocity, particle distribution, the material of elements, etc. These parameters are analyzed in different operational conditions of geothermal turbines. Based on the numerical results, design modifications were developed for the studied elements of the turbines, for the purpose of getting a substantial reduction of erosion rate and thereby reducing energy losses. Main design modifications to avoid erosion problem of the elements of the turbines consist of modifying the fluid flow pattern to reduce their influence on the erosion rate. This is obtained by reducing flow velocity, changing trajectories of solid particles and changing the angle of impact of solid particles on the surface of the analyzed elements. The results show that it is possible to reduce th
Entidades citadas de la UNAM:
ISBN:
9781619427655
Editorial:
Nova Science Publishers, Inc. Nombre de la publicación:
Analysis and control of erosion in geothermal turbines
Página inicial:
195
Página final:
226
Tipo de producto:
Capítulo de un Libro
