METHOD OF MODELLING GAS TURBINE PERFORMANCE

Abstrakt

The basis of a combined cycle gas turbine mass and energy balance, carried at the concept stage, preliminary design or during analysis, is the calculation of the gas turbine design point. This article presents a gas turbine unit mathematical modelling process intended for implementation of the model in a computer program. The aim of the development was a relatively simple, practical from engineer’s point of view, and universal gas turbine model with a classic, open system design: compressor – combustion chamber – turbine. Attempts have been made to maintain the accuracy of modelling and to keep the ability for extension of the model so to be able to simulate the operation of the turbine at off-design conditions, in particular at part load. Stationary operation of the unit at nominal load is assumed. Thermodynamic system modelling methods, on the level of its global structure, have been submitted. Problems related to the aforementioned issues are discussed and ways to resolve them proposed. The developed model has been implemented in a dynamic link library written in C++ language with usage of C/C++ Minpack numerical library [Keating 2007, Razak 2007].

Keywords:
gas turbine, Brayton cycle, numerical simulation, mathematical modelling, steady state analysis, energy system