An Integrated Method for Propulsion System Conceptual Design

The conceptual design of future, potentially highly integrated aircraft engines pose a variety of new design options to the propulsion system engineers. In order to find the best conceptual design, rapid evaluation of many design choices is essential. However, traditional, fast evaluation methods employing historical and empirical data can only be applied to novel engine concepts to a very limited degree. Thus, swift conceptual design methods based on physical approaches providing a sophisticated level of detail are needed. The current paper presents a methodology focused on conceptual engine design. The methodology is based on the gas turbine simulation framework GTlab, which integrates software tools for engine performance, component aerodynamics and structural design. For conceptual design a dedicated set of design tools exists — the so called GTlab-Sketchpad. Sketchpad tools have full access to the thermodynamic design data of the engine performance module. Based on cycle analysis, the tool set generates parametric representations of the propulsion system components and stores the results back to the frameworks data model. Computational time is limited to a few seconds, to ensure interactivity during the design process. The graphical user interface provides means to interactively modify the design parameters and to immediately evaluate their impact on the overall design. Since the internal data model facilitates three dimensional parameterizations of the engine components, 3D representations of the engine designs can be generated by interfacing an open source CAD-kernel. For the present paper, the conceptual design process of a commercial jet engine utilizing GTlab-Sketchpad is shown. The underlying computational methods are described and the resulting 3D-geometry is presented.