Energy Efficiency of Nozzles for Axial Microturbines

Autor: M. Yu. Fershalov, A.Yu. Fershalov, Yu.Ya. Fershalov
Rok vydání: 2017
Předmět:
Zdroj: Procedia Engineering. 206:499-504
ISSN: 1877-7058
DOI: 10.1016/j.proeng.2017.10.507
Popis: The work is devoted to solving important problems of applied gas dynamics of turbine stages, concerning the low efficiency of the nozzle apparatus axial microturbines (angles of exit nozzles do not exceed 9 °), operating at supercritical differences of enthalpy, and is aimed at increasing the speed ratio of the nozzle apparatus (the ratio of actual downstream speed of the nozzle apparatus to the maximum possible - theoretical flow rate) and the prediction angle downstream from it. The work is based on the results of mathematical modeling of gas-dynamic processes based on the of the results of a physical experiment. The results are presented as a formalized mathematical regression model type functions - the machine nozzle velocity and flow rate output therefrom angle depending on the following factors - the expansion nozzle; nozzle exit angle; angle of the front edge of the impeller; the theoretical value of the Mach number; dimensionless peripheral speed. Such a presentation of the results allows not only for their numerical analysis and physical interpretation of the purpose of a comprehensive assessment of the impact on the speed ratio of the nozzle apparatus and the downstream corner of it, studied factors, but also for the performance of the optimization calculations.
Databáze: OpenAIRE