Lightweight Turbogenerator for VTOL UAV

The Navy is developing a new type of UAS for small-deck ships that can operate from these platforms but that provide the endurance and range of a conventional fixed-wing UAS. These UASs are tail-sitting and take off and land vertically (VTOL) while flying horizontally. The Navy is seeking propulsion systems for these UASs that have high specific power, but also have reasonable efficiency (SFC). The propulsion system must also be orientation insensitive and compatible with marine environments. Class 3 UAS propulsion is typically supplied by internal combustion engines, which have good SFC, but are heavy and have poor specific power. Gas turbine engines have excellent specific power, but typically have poor SFC at this scale. This topic is seeking a turbogenerator for a Class 3 VTOL UAS that has both high specific power and low SFC. Creare and UAV Turbines have been developing a 50 hp recuperated turbogenerator for a ground power application. This engine has efficient turbomachines, generator, and recuperator, and easily meets the SFC requirements for this topic. The main challenge is in the specific power requirement. We plan to adapt our existing ground-power turbogenerator to meet the NavyÆs requirements for VTOL UAS propulsion. We plan to utilize many of the existing components used in the existing turbogenerator, but we will implement air bearings for mass reduction to meet the specific power requirements. Air bearing design and analysis will be supported by our academic collaborators at Texas A&M. In Phase I, we will focus on bearing design and rotodynamic analysis, and development of a bearing test rig for air bearing testing. We will also predict the performance of the final turbogenerator using analysis. In Phase II, we will develop and test a fully integrated turbogenerator. The turbogenerator developed under this program will be commercialized as a UAV Turbines product for direct sale to Navy programs or other commercial applications.