Integrated Flow Control Devices for the Design of Enhanced Low Pressure Turbines

摘要

Flow separation limits the efficiency of low-pressure turbines (LPTs) in aircraft engines. Experiments with vortex generator jets (VGJs), conducted in AFRL's low-speed cascade at Wright-Patterson AFB, have demonstrated dramatic reductions in separation losses. The critical science that will enable this design innovation to reach its potential is a comprehensive understanding of the effect of VGJs on a separating boundary layer. Experiments were conducted at BYU to better understand the basic physics of the separation control phenomenon and establish the quantitative links between the underlying flow physics and LPT performance. Understanding gained from these experiments was used to guide the design of a new, high-performance LPT blade at AFRL. The Air Force design codes used to generate the new airfoil included provisions for flow control using vortex generator jets. Experiments with the new profile confirmed the design goal of a 17% increase in blade loading compared to industry standard.