Search for dissertations about: "ultra high bypass ratio"

Found 4 swedish dissertations containing the words ultra high bypass ratio.

  1. 1. Aerodynamic Design and Experimental Investigation of Short Nacelles for Future Turbofan Engines

    Author : Vinícius Tavares Silva; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ultra-high-bypass turbofan; Computational Fluid Dynamics; powered nacelle.; Ultra-short nacelles; experimental; thrust-and-drag bookkeeping;

    Abstract : To achieve a higher propulsive efficiency, and hence reduced fuel burn and emissions, the next generation turbofan engines are expected to have higher bypass ratios and lower fan pressure ratios. However, the larger the bypass ratio, the larger becomes the fan and thus the nacelle. The result is an undesired increase in weight and nacelle drag. READ MORE

  2. 2. On the Analysis of Energy Efficient Aircraft Engines

    Author : Oskar Thulin; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Performance modelling; Aero engine; Turbofan; Aircraft engine; Installed propulsion; Ultra high bypass ratio; Exergy analysis; Engine weight estimate; Variable area fan nozzle; Multiple pivoting flaps; Translating cowls;

    Abstract : Aero engine performance analysis is highly multidimensional using various measures of component performance such as turbomachinery and mechanical efficiencies, and pressure loss coefficients. Using conventional performance analysis, relying on only the laws of thermodynamics, it is possible to understand how the performance parameters affect the component performance, but it is difficult to directly compare the magnitude of various loss sources. READ MORE

  3. 3. Aerodynamic Aspects of Propulsion Integration for Next-generation Commercial Aircraft

    Author : Vinícius Tavares Silva; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Propulsion integration; Ultra-high-bypass-ratio engines; Low-speed testing.; Aerodynamics; Computational Fluid Dynamics; Ultra-short nacelles over-wing nacelle;

    Abstract : Propulsion integration is one of the most challenging aspects of aircraft design. It requires a multidisciplinary approach involving aerodynamics, propulsion, structures, weight, noise, and control systems. READ MORE

  4. 4. Physics-based Modelling for Aircraft Noise and Emission Predictions

    Author : Evangelia Maria Thoma; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; measurements; trajectories.; emissions; interdependencies; FDR; turbofan engine; aircraft noise; physics-based modelling;

    Abstract : Starting from semi-empirical noise source models for the aircraft and 4D trajectory computations, this work focuses on the environmental assessment of scenario studies regarding technology evaluation and procedural planning. Extensive work was performed on improving and validating the existing tools. READ MORE