Multidisciplinary Design Methodology for Micro-Gas-Turbines - Part I: Reduced Order Component Design and Modelling

Abstract

Ultra micro gas turbines (UMGT) for electric power generation up to 1 kW are a viable replacement technology for lithium batteries in drones due to their high energy density. Previous research has shown that small-scale effects disqualify conceptual design practices applied to larger gas turbines owing to highly coupled, non-linear component interactions. To fill this gap, we propose an interdisciplinary conceptual design and analysis framework based on reduced order models. To this end, the current work is divided into two parts covering component design and system integration, analysis and optimization. In Part I, automated conceptual design of all engine sub-components is elaborated facilitating interdependent reduced order models for compressor, turbine, combustor and high-speed generator, while also considering additive manufacturing constraints. In a second step, the reduced order performance models are compared to CFD RANS simulations of various turbomachinery geometries as well as experimental data of combustor and high-speed generator prototypes, showing good agreement and thus validating the component modules. In conclusion, the first part of this work elaborates an automated and efficient method to conceptual design of all components required for a functional UMGT. Since the strategy is applicable independent of component arrangement and engine layout, the proposed methods offer a universal framework for small gas turbine generators.