Three-Stream Gas Turbine Architecture for Thrust and Thermal Management

The patent divides the airflow into three separate streams: a core stream through the combustor, a first bypass stream around the core, and a second bypass stream outer than the first. This segmentation allows each stream to be optimized independently, enabling the fan diameter to be increased for higher thrust while managing thermal loads and installation constraints through distributed airflow paths.

The patent introduces a radial dimension to the bypass airflow by creating an annular passage between the core cowl and the fan duct, forming a second bypass stream that flows radially outward. This dimensional addition allows for increased fan diameter and thrust while distributing thermal management requirements across multiple spatial zones.

The patent segments the bypass airflow into two distinct streams with separate control mechanisms: a first bypass stream controlled by inlet guide vanes and a second bypass stream controlled by outlet guide vanes. This segmentation enables independent optimization of airflow ratios to reduce engine weight and improve packaging while maintaining manageable structural complexity through modular control systems.

The patent employs variable geometry components including movable inlet guide vanes and outlet guide vanes that can adjust the airflow distribution between the core stream and the two bypass streams. This dynamic control allows optimization of airflow ratios for weight reduction and packaging improvement while maintaining structural adaptability rather than fixed simplicity.

The patent applies variable geometry components at specific locations where they provide maximum benefit: inlet guide vanes at the fan duct inlet to control the first bypass stream, and outlet guide vanes at the core cowl to control the second bypass stream. This localized application of complexity optimizes propulsive efficiency by controlling airflow distribution precisely where needed, rather than throughout the entire engine.

The variable geometry components serve multiple functions: the inlet guide vanes control both the direction and distribution of the first bypass stream, while the outlet guide vanes regulate the second bypass stream and affect core airflow. This multi-functionality reduces the need for separate control mechanisms, thereby limiting the increase in device complexity while achieving improved propulsive efficiency through optimized airflow ratios.