Akademik Veri Yönetim Sistemi
8th INTERNATIONAL CONGRESS ON ENGINEERING AND SCIENCES, İstanbul, Türkiye, 14 - 15 Mart 2026, ss.294-301, (Tam Metin Bildiri)
This study includes the dynamic modeling, validation, and control system design of a sample turbojet engine based on the T-MATS (Toolbox for the Modeling and Analysis of Thermodynamic Systems) library, developed by NASA for the Matlab/Simulink environment. Unlike iterative solution methods common in the literature, the state variable method was adopted to realistically reflect the engine's transient behaviors. The selected state variables determining engine dynamics were shaft speed (N), compressor outlet pressure (P2), and turbine outlet pressure (P4). During modeling, inter-component control volumes were defined between the compressor and combustion chamber (V1), and between the turbine and nozzle (V2). By applying conservation of mass and energy laws to these volumes, pressure and speed derivatives were obtained, solving the system dynamically. Individual components were modeled by successfully integrating characteristic performance maps from the T-MATS sample. The developed model demonstrated a high degree of agreement with the reference T-MATS model in both steady-state and dynamic responses. During the controller design phase, surge and choke lines were analyzed to establish an industry-standard min-max fuel limiting structure with a 10% safety margin. Addressing the engine's non-linear characteristics, the operating range was divided into slow, medium, and fast operation regions. A gain-scheduled PI controller was designed, featuring parameters tuned via the Ziegler-Nichols open-loop method and a clamping-type integral anti-windup mechanism. Consequently, the controller demonstrated successful tracking performance in the transient region but exhibited oscillatory behavior in the steady-state region. Performance criteria like overshoot and settling time were analyzed, noting that the controller reached saturation at certain shaft speeds. Future studies aim to resolve these issues and optimize system performance using different parameter tuning techniques.