Conceptualizing a Pre-Assembled Additively Manufactured Gas Turbine Engine: Technological Feasibility

This study introduces a groundbreaking micro-jet engine design for UAVs, presenting a cost-effective alternative to conventional micro-gas turbines through a unique engine architecture that allows additive manufacturing in a single, uninterrupted print, thus significantly reducing production costs. The design is streamlined into two main components: a rotating element and a stationary part. Central to this innovation is the non-conventional structure integrating a static casing with an embedded combustion chamber and a singular rotating shell that combines compressor and turbine functionalities. The architecture of the entire engine has been developed with a keen focus on the constraints and requisites inherent to additive manufacturing, specifically emphasizing 'self-supported' structures. A distinctive feature of presented design is the use of a hydrostatic bearing system, with fuel as the lubricant for the rotating part. The preliminary dimensions and evaluation of the bearing were initially conducted using commercial software, followed by an extensive CFD analysis. A key aspect of the study is the examination of the feasibility of manufacturing a pre-assembled engine, inclusive of its rotor and bearing housing, and the subsequent evaluation of the manufacturability of such intricate structures with minimal clearance tolerances. This objective was realized through a systematic examination of pre-assembled, printed test specimens encompassing a spectrum of clearance dimensions and angular configurations. Subsequently, an optimization process for the pre-deformation of the engine rotor was undertaken.