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- Aircraft (3)
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- UAV (2)
- ANSYS FLUENT (1)
- Aerodynamic heating (1)
- Computational Fluid Dynamics (1)
- Contact fatigue (1)
- Drag (1)
- Dual-plane airfoil (1)
- Flooded lubrication (1)
- Gap, stagger and decalage (1)
- High-speed (1)
- Large Eddy Simulation (1)
- Lighter-Than-Air Vehicles (1)
- Modelica (1)
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- Particle image velocimetry (1)
- Power generation (1)
- Pressure testing (1)
- Rankine Cycle (1)
- S826 dual-plane airfoil (1)
- Spur gear contact (1)
- Starvation effect on fatigue crack initiation (1)
- Starved lubrication (1)
Articles 1 - 6 of 6
Full-Text Articles in Engineering
Development Of A Combined Thermal Management And Power Generation System Using A Multi-Mode Rankine Cycle, Nathaniel M. Payne
Development Of A Combined Thermal Management And Power Generation System Using A Multi-Mode Rankine Cycle, Nathaniel M. Payne
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Two sub-systems that present a significant challenge in the development of high performance air vehicle exceeding speeds of Mach 5 are the power generation and thermal management sub-systems. The air friction experienced at high speeds, particularly around the engine, generates large thermal loads that need to be managed. In addition, traditional jet engines do not operate at speeds greater than Mach 3, therefore eliminating the possibility of a rotating power generator. A multi-mode water-based Rankine cycle is an innovative method to address both of these constraints of generating power and providing cooling. Implementing a Rankine cycle-based system allows for the …
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
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A set of guidance control laws is developed for application to a reduced order dynamic aircraft model. A feedback control formulation utilizing a linear quadratic regulator (LQR) is developed, together with methods for easing the design burden associated with gain tuning. Metrics are developed to assess the stability margin of the controller over the full flight envelope of a notional unmanned aerial vehicle (UAV) model. A feedforward control path is then added to the architecture. The performance of the guidance control laws is assessed through time domain step response metrics as well as through execution of a design mission. The …
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
Development Of A Robust And Tunable Aircraft Guidance Algorithm, Jacob R. Spangenberg
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A set of guidance control laws is developed for application to a reduced order dynamic aircraft model. A feedback control formulation utilizing a linear quadratic regulator (LQR) is developed, together with methods for easing the design burden associated with gain tuning. Metrics are developed to assess the stability margin of the controller over the full flight envelope of a notional unmanned aerial vehicle (UAV) model. A feedforward control path is then added to the architecture. The performance of the guidance control laws is assessed through time domain step response metrics as well as through execution of a design mission. The …
Performance Of A Dual Plane Airfoil Model With Varying Gap, Stagger, And Decalage Using Pressure Measurements And Particle Image Velocimetry, Salome Kenneth Nunes
Performance Of A Dual Plane Airfoil Model With Varying Gap, Stagger, And Decalage Using Pressure Measurements And Particle Image Velocimetry, Salome Kenneth Nunes
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The dual-plane airfoil has been adopted in the design of aircraft wings, wind turbine blades, and propellers. The purpose of this research is to investigate the most important design parameters of a dual-plane airfoil model for the best aerodynamic performance, such as gap, stagger, and decalage. The dual-plane airfoil model was designed using the S826 profile. A mechanical mechanism with electrical actuator control is particularly designed to alter the gap and stagger smoothly, as well as the angle of attack (AOA) for each airfoil. It results in a gap range of 1.38c to 2.17c, a stagger range of -0.75c to …
Contact Fatigue Of Spur Gear Operating Under Starved Lubrication Condition, Aparna Udthala
Contact Fatigue Of Spur Gear Operating Under Starved Lubrication Condition, Aparna Udthala
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This study describes contact fatigue behavior of spur gear contacts operating under mixed elastohydrodynamic condition. The focus is placed on the starvation effect on fatigue crack initiation. With the model, parametric simulations are carried out with different contact parameters. In the process, the lubricant supply is varied to alter the lubrication condition from fully flooded to severely starved circumstance. Multi-axial stress fields induced by surface normal and tangential tractions are evaluated, whose amplitudes and means are used in a multi-axial fatigue criterion to determine the crack initiation life. It is found a lower lubricant viscosity elongates fatigue life when severe …
Numerical Investigation Of Flow Around A Deformed Vacuum Lighter-Than-Air Vehicle, Jared N. Kerestes
Numerical Investigation Of Flow Around A Deformed Vacuum Lighter-Than-Air Vehicle, Jared N. Kerestes
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This study characterizes the functional dependence of drag on Reynolds number for a deformed vacuum lighter-than-air vehicle. The commercial computational fluid dynamics (CFD) code, FLUENT, is used to preform large eddy simulations (LES) over a range of Reynolds numbers; only Reynolds numbers less than 310,000 are considered. While the overarching goal is drag characterization, general flow-field physics are also discussed, including basic turbulence spectra. All large eddy simulations are preceded by a Reynolds-averaged Navier-Stokes (RANS) simulation using Menter’s shear stress transport (SST) model. The precursor RANS simulation serves to (1) provide realistic initial conditions, (2) decrease the time needed to …