Comprehensive evaluations on performance and energy consumption of pre-swirl rotor-stator system in gas turbine engines

摘要

Pre-swirl system has an indispensable role to supply enough cooling air with appropriate pressure, temperature, and mass flow rate to improve the life and the efficiency of turbine cooling blades and vanes. This study aimed to reveal the heat transfer mechanism and energy conversion characteristics of a multi-in and multi-out pre-swirl system. Subsequently, a novel modified prediction modeling was proposed to evaluate the system performance and energy conversion with complete consideration of multi-factors, especially for determining the influence of the seal flow, wall friction, work done by the rotating turbine disc, and rotor-stator moment. The results reveal that a high pre-swirl cooling performance and low-energy consumption can be obtained from the contribution of the airflow swirl ratio, whereas the swirl ratio was susceptible to the mixed seal flow. Thereafter, the seal outflow improved the system temperature-drop efficiency, whereas the seal inflow strongly influenced the heat transfer and energy consumption characteristics. The modified modeling resulted in a 56.89% increase in prediction accuracy relative to the Liu-model. Moreover, the nonlinear relationships between the seal flow and system performances can be comprehensively and accurately evaluated. In particular, a peak in a system temperature drop of 38.5 K can be realized with a low-energy consumption of -133 kW and a 64% enhancement in the airsupply flow rate based on a contribution of the seal flow on airflow swirl ratio. Thus, the implementation of the modified modeling can prove significant in theoretical guidance and engineering applications.