Dynamic analysis of two-wheel bleed air environment control system of the aircraft

Abstract Dynamic analysis of the environment control system plays a crucial role in improving system performance and control. This article describes the Dynamic analysis of a two-wheel bleed air environment control system for the aircraft. An environment control system library of Dymola software was used to develop the Dynamic model of a 2-wheel bleed air environment control system. Dymola is a commercial 1-D dynamic simulation software based on the Modelica language. An analysis was carried out on the key components of the two-wheel bleed air high-pressure water separator environment control system. The Dynamic response obtained from the model in terms of hot side heat flow rate for the core compact heat exchangers, outlet temperature on the hot and cold side for the heat exchangers, the outlet temperature of the cold air unit, as well as corrected flow and corrected speed of the cold air unit. The dynamic response is also obtained for the shaft power, torque, and angular speed. As per the literature, a separate steady-state analysis has been done in the MATLAB code for validation due to the unavailability of a Dynamic study on a two-wheel high-pressure water separator bleed air environment control system. The simulation results demonstrate a strong level of accuracy when compared to the steady-state analysis. The system-level Dynamic response was obtained around 26 seconds, 52 seconds, and 78 seconds at mass moment of inertia of the cold air unit shaft 0.01 kgm 2 , 0.02 kgm 2 , and 0.03 kgm 2 , respectively, validated against MATLAB steady-state results. The Dynamic model developed can be utilized during the initial design phase of the system when actual experimental data is unavailable.