Experimental analysis and modeling of gas turbine engine performance: Design point and off-design insights through system of equations solutions

In this article, a systematic approach is presented for simulating turbojet engine performance at both design and off-design points. The construction of gas turbine engines involves a core, with additional components added based on the proposed methodology. Accurate formulation of component characteristics and their matching forms the basis for the system of equations needed for solving off-design engine performance. The developed algorithm's initial step involves comparing results with experimental data obtained from 230 N engines. Experimental testing utilizes a 780 N engine under diverse operating conditions, allowing determination of thrust values, fuel consumption, and outlet gas temperatures. An engine characteristic curve is derived under static conditions at ground level and validated against ground test results in Tehran. Unknown parameters are calibrated using a dedicated model, enabling the extraction of engine performance parameters across different corrected speeds. These results are then compared with GasTurb outputs. Comparative analysis between the proposed model's simulation and experimental data demonstrates high accuracy, affirming the reliability of the presented model.