Aeromechanics & Rotordynamics
The current design trend towards large, low fan-pressure ratio propulsors and small gas generator cores presents a new class of aeromechanical and rotordynamic challenges. The goal of ensuring robust engine design and operation motivates investigation into improving current diagnostic and prognostic methodologies in characterization of engine aeromechanics and rotordynamics.
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Current Research Projects
Robust Operation and Performance Limiting Mechanisms in Kilowatt-Scale High-Speed Gas Turbine Engines
J. Chiapperi
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We are researching small gas turbine engines for remote power generation applications. Fuel-based energy systems can provide a much higher energy density than battery-electric systems, making them ideal candidates for portable power systems, such as unmanned aerial vehicles and autonomous robots. Traditionally, applications in the kilowatt scale would be filled by reciprocating piston engines. Here, we study the potential use of gas turbine engines in the kilowatt scale. Gas turbines have the potential for higher power density, superior mechanical reliability, and greater fuel flexibility when compared to piston engines. The primary challenges are ensuring stable operation and acceptable efficiency.
Forced Response System Identification in Rocket Engine Turbopumps
M.C. Campbell
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The current characterization of inducer cavitation dynamics, especially the so-called pump transfer matrices, is still limited as the only experimental transfer matrix data available dates back to the 1970s. There is a critical need for more in-depth experimental characterization of the cavitation dynamics and related damping in turbopump inducers so as to allow a more accurate and reliable assessment of instability. The goal of the project is to conduct forced response system identification experiments aimed at characterizing the cavitation dynamics.
A Reduced Order Model Framework for Operability Assessment of Damaged Blades
K. Wong
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Characterizing aeroengine operability limits has been a challenge within the aerospace industry. Due to safety concerns, the performance degradation of damaged engines has been difficult to quantify through live testing and has relied upon computational fluid dynamics (CFD) simulations to assess operability limits. Due to the high computational cost of high fidelity CFD models, it is unrealistic to analyze and determine a comprehensive operability limit for the engines. This often results in replacing the entire part or engine that is considered damaged which results in high manufacturing and overhaul costs. To improve operability limits and potentially mitigate operating cost, a reduced order model (ROM) will be developed. The development of ROM that can capture the unsteady characteristics of damaged compressor blades will be used to demonstrate the robustness of an unsteady body force model (BFM) as a sound validation tool for improving performance and providing useful operability guidelines.
Reduced Order Modeling of Turbopump Inducers for Launch Vehicle Dynamical Systems
M. Hussein
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This research introduces a new opportunity for dynamical system modeling capturing the structural dynamics effects, and thus demonstrates benefits of coupled dynamical system model for characterization of Pogo instability with direct link to inducer and pump design.