Vol.1, No 7, 2000 pp. 871 - 878
UDC 621.134.5:519.87
NONLINEAR MATHEMATICAL MODEL
OF THE CONDENSING STEAM TURBINE
Dragoljub Živković
Faculty of Mechanical Engineering, Beogradska 14, 18000 Niš
E-mail: dzivkovic@masfak.masfak.ni.ac.yu
Abstract. In this paper a nonlinear mathematical model of the condensing steam turbine, which gives essential new possibilities compared with linear models, is presented. This model enables: researches of work regimes of the steam turbines in wide range of the loading, making simulators for education working staff, analysis starting, stopping and accidental regimes and solving other problems.
Nonlinear mathematical model is built of some turbine element models (turbine rotor, regulating and stopping valve, steam rooms, group of stages) and steam reheater, in structural way. The above mentioned elements are presented like objects with disposed and concentrated steam parameters. Mathematical model is presented by the system of: nonlinear partial hyperbolic differential equations, ordinary nonlinear differential equations and algebraic equations.
System of equations is solved by method of characteristics and method of finite differences. Original software is developed for numerical simulation. The results of the simulations of the steam-turbine work regimes after protection system action and during impulsive response are presented in this paper.
NELINEARNI MATEMATIČKI MODEL
KONDENZACIONE PARNE TURBINE
U radu je dat nelinearni matematički model kondenzacione parne turbine, koji omogućuje analizu rada u širokom opsegu opterećenja, simulaciju u edukacione svrhe, analizu starta, zaustavljanja i ispada turbine kao i mnogih drugih scenarija. Nelinearni matematički model je struktuiran na bazi modela za pojedine elemente turbine i sadrži nelinearne hiperbolične parcijalne diferencijalne jednačine, obične nelinearne diferencijalne jednačine i algebarske jednačine.
Sistem jednačina je rešen metodom karakteristika i metodom konačnih razlike. Na bazi toga bila je moguća simulacija rada parne turbine pri raznim scenarijima.