development of a 3d printed 300w micro gas turbine
TRANSCRIPT
RESEARCH GOAL: MICRO TURBINE GENERATOR FOR UAVs• Hybrid energy supply system: battery buffer charged by micro gas turbine• Energy density of up to 1200 kWh/kg due to high kerosene energy density• Flight time increased 4-6 times compared to Lithium Polymer batteries
Development of a 3D Printed
300W Micro Gas Turbine
Turbomachinery and Heat Transfer LaboratoryPhD Student Lukas Badum, Asst. Prof. Beni Cukurel
CHALLENGES AND PROPOSED INNOVATIONSThe main obstacles to successful UMGT development were manufacturingconstraints, heat transfer management and air bearing instability. These willbe overcome by the following innovations:• Additive Manufactured High-Speed Rotors
-> geometrical flexibility, high TIT• Hollow rotor
-> reducing material agglomeration, heat transfer to compressor, turbine surface temperature
• High-speed hybrid ceramic bearings instead of air bearings-> reliability, no whirl instability, high stiffness, off-the-shelf components
Micro Gas Turbine
Electronics Battery Buffer
Fuel Tank
System weight: 200-300g
𝑷𝒆𝒍 = 𝟑𝟎𝟎𝑾
ROTOR ADDITIVE MANUFACTURINGHigh-speed rotors have been manufactured using different materials and
manufacturing technologies:1. Inconel 718: High temperature capable nickel alloy2. Silicon Nitride: Excellent ceramic for temperatures above 1000°C3. Alumina: Easy-to-manufacture ceramic for high temperature applications
REDUCED ORDER ENGINE MODEL
INTERDISCIPLINARYENGINE OPTIMIZATION
Balancingmarks
UMGT Concept
Turbo-machinery
Turbo-machinery
Thermo-dynamic Analysis
Thermo-dynamic Analysis
Stress Analysis
Stress Analysis
Rotor Dynamics
Rotor Dynamics
Heat
Transfer
Heat
Transfer
Generator Design
Generator Design
Porous Combustor
Porous Combustor
SiNi Rotor
Inconel Rotor
Rotor 3D Scan Balanced Rotor
Roller Bearing
Generator Coil
Permanent Magnet + Sleeve
Radial Compressor
Radial Turbine
Fuel Inlet
Porous Media Combustor
Glow Plug
AirAxial Inlet
Hollow Rotor,Internal cooling
6 cmUMGT Concept
Generator: 2D Magnetostatic Model• Solving Laplace’s equation for magnetic
vector potential in polar coordinates:
𝝏𝟐𝑨
𝝏𝒓𝟐+𝟏
𝒓
𝝏𝑨
𝝏𝒓+𝟏
𝒓𝟐𝝏𝟐𝑨
𝝏𝜽𝟐= 𝟎
• Loss modelling• Stator Iron Losses• Copper Losses• Air friction Losses
Rotordynamic Model• Axisymmetric modelling• Bearing stiffness according to manufacturer data
𝑼𝟔
𝑪𝟔
𝑾𝟔
𝜶𝟔
𝜷𝟔𝒎
Compressor and Turbine Models• Meanline design based on non-dimensional parameters• Automatic 3D geometry generation• Loss modelling for efficiency estimation
𝑼𝟒
𝑪𝟒𝑾𝟒
𝜶𝟒
𝜷𝟒,𝒐𝒑𝒕~ − 𝟐𝟎°
𝜷𝟒𝒊𝟒
HIGH SPEED TESTING AND MODEL VALIDATION• Successful testing up to design speed of 500,000 rpm (cold gas)• Validation of component efficiency, heat transfer models
RotorBearing Casing Turbine ScrollMCR
Radial Turbine Velocity Triangles
Resulting Magnetic Field
NEXT STEPS• Finalize engine model• Hot gas testing• Prototype design and testing