Robust Gas Turbine and Airframe System Design in Light of Uncertain
Robust Gas Turbine and Airframe System Design in Light of Uncertain Fuel and CO2 Prices Stephan Langmaak1, James Scanlan2, and András Sóbester3 University of Southampton, Southampton, SO16 7QF, United Kingdom This paper presents a study that numerically investigated which cruise speed the next generation of short-haul aircraft with 150 seats should y at and whether a con- ventional two- or three-shaft turbofan, a geared turbofan, a turboprop, or an open rotor should be employed in order to make the aircraft's direct operating cost robust to uncertain fuel and carbon (CO2) prices in the Year 2030, taking the aircraft pro- ductivity, the passenger value of time, and the modal shift into account. To answer this question, an optimization loop was set up in MATLAB consisting of nine modules covering gas turbine and airframe design and performance, ight and aircraft eet sim- ulation, operating cost, and optimization. If the passenger value of time is included, the most robust aircraft design is powered by geared turbofan engines and cruises at Mach 0.80. If the value of time is ignored, however, then a turboprop aircraft ying at Mach 0.70 is the optimum solution. This demonstrates that the most fuel-ecient option, the open rotor, is not automatically the most cost-ecient solution because of the relatively high engine and airframe costs. 1 Research Engineer, Computational Engineering and Design 2 Professor of Aerospace Design, Computational Engineering and Design, AIAA member 3 Associate Professor in Aircraft Engineering, Computational Engineering and Design, AIAA member 1 I. Introduction A. Background IT takes around 5 years to develop a gas turbine engine, which then usually remains in pro- duction for more than two decades [1, 2].
[Show full text]