Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- 3D printers (1)
- Aircraft (1)
- Atmospheric modeling (1)
- Bond energy (1)
- Boundary layers (1)
-
- Centrifugal Forces (1)
- Chlorine compounds (1)
- Computational modeling (1)
- Convective heat transfer (1)
- Fenders (port structures) (1)
- Fluorescence (1)
- Fluorescence thermometry (1)
- Frequency dependence (1)
- Frequency division multiplexing (1)
- Frequency range (1)
- Frequency ratios (1)
- Friction (1)
- Fuel pyrolysis (1)
- Fuel regression rates (1)
- Hardware (1)
- Heat convection (1)
- Heat flux (1)
- Heat transfer (1)
- Hybrid rockets (1)
- Inelastic scattering (1)
- Inter-diffusion (1)
- Laser excitation (1)
- Mass differences (1)
- Mathematical model (1)
- Modulation frequencies (1)
Articles 1 - 6 of 6
Full-Text Articles in Engineering
Software-And Hardware-In-The-Loop Verification Of Flight Dynamics Model And Flight Control Simulation Of A Fixed-Wing Unmanned Aerial Vehicle, Calvin Coopmans, Michal Podhradsk, Nathan V. Hoffer
Software-And Hardware-In-The-Loop Verification Of Flight Dynamics Model And Flight Control Simulation Of A Fixed-Wing Unmanned Aerial Vehicle, Calvin Coopmans, Michal Podhradsk, Nathan V. Hoffer
Mechanical and Aerospace Engineering Faculty Publications
Unmanned aerial system (UAS) use is ever-increasing. In this paper, it is shown that even with low-cost hardware and open-source software, simple numerical testing practices (software- and hardware-in-the-loop) can prove the accuracy and usefulness of an aeronautical flight model, as well as provide valuable pre-flight testing of many situations typically only encountered in flight: high winds, hardware failure, etc. Software and hardware simulation results are compared with actual flight testing results to show that these modeling and testing techniques are accurate and provide a useful testing platform for a small unmanned aerial vehicle. Source code used in simulation is open …
Wideband Fluorescence-Based Thermometry By Neural Network Recognition: Photothermal Application With 10 Ns Time Resolution, Liwang Liu, Kuo Zhong, Troy Munro, Salvador Alvarado, Renaud Cote, Sebastiaan Creten, Eduard Fron, Heng Ban, Mark Van Der Auweraer, N. B. Roozen, Osamu Matsuda, Christ Glorieux
Wideband Fluorescence-Based Thermometry By Neural Network Recognition: Photothermal Application With 10 Ns Time Resolution, Liwang Liu, Kuo Zhong, Troy Munro, Salvador Alvarado, Renaud Cote, Sebastiaan Creten, Eduard Fron, Heng Ban, Mark Van Der Auweraer, N. B. Roozen, Osamu Matsuda, Christ Glorieux
Mechanical and Aerospace Engineering Faculty Publications
Neural network recognition of features of the fluorescence spectrum of a thermosensitive probe is exploited in order to achieve fluorescence-based thermometry with an accuracy of 200 mK with 100 MHz bandwidth, and with high robustness against fluctuations of the probe laser intensity used. The concept is implemented on a rhodamine B dyed mixture of copper chloride and glycerol, and the temperature dependent fluorescence is investigated in the temperature range between 234 K and 311 K. The spatial dependence of the calibrated amplitude and phase of photothermally induced temperature oscillations along the axis of the excitation laser are determined at different …
Contributions Of Mass And Bond Energy Difference And Interface Defects On Thermal Boundary Conductance, Nicholas A. Roberts, Changjin Choi
Contributions Of Mass And Bond Energy Difference And Interface Defects On Thermal Boundary Conductance, Nicholas A. Roberts, Changjin Choi
Mechanical and Aerospace Engineering Faculty Publications
The impact of mass and bond energy difference and interface defects on thermal boundary conductance (TBC) is investigated using non-equilibrium molecular dynamics (NEMD) with the Lennard-Jones (L-J) interatomic potential. Results show that the maximum TBC is achieved when the mass and bond energy of two dissimilar materials are matched, although the effective thermal conductivity is not necessarily a maximum due to the contributions of the thermal conductivity of the constituent materials. Mass and bond energy differences result in a mismatch between phonon dispersions, limiting high frequency phonon transport at the interface. This frequency mismatch is defined by a frequency ratio, …
High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Stephen A. Whitmore, Sean D. Walker, Daniel P. Merkley, Mansour Sobbi
High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Stephen A. Whitmore, Sean D. Walker, Daniel P. Merkley, Mansour Sobbi
Mechanical and Aerospace Engineering Faculty Publications
Results froma development campaign, where modern additive manufacturing methods are used to fabricate hybrid rocket fuel grains with embedded helical ports, are presented. The fuel grains were constructed from acrlyonitrile butadiene styrene using commercially available three-dimensional printer feedstockmaterial.Gaseous oxygen is used as the oxidizer for this test campaign.When compared to cylindrical fuel ports, significant increases in fuel regression rates were observed, and these increases in regression rate diminished with time as the helical fuel port burns to become progressivelymore cylindrical. Comparisons to the helical pipe flow skin friction correlation developed by Mishra and Gupta indicate that increased skin friction only …
Matryoshka Cavity, Randy Craig Hurd, T. Fanning, Zhao Pan, C. Maybey, Kyle G. Bodily, Kip Schafer Hacking, Nathan B. Spiers, Tadd T. Truscott
Matryoshka Cavity, Randy Craig Hurd, T. Fanning, Zhao Pan, C. Maybey, Kyle G. Bodily, Kip Schafer Hacking, Nathan B. Spiers, Tadd T. Truscott
Mechanical and Aerospace Engineering Faculty Publications
When a water droplet impacts a free surface with sufficient velocity, the momentum transfer results in the formation of a hemispherical cavity expanding radially from the point of impact.1 This cavity continues to expand until the kinetic energy is completely converted to potential energy (Fig. 1(a)).2 Pumphrey and Elmore equated the potential energy of this subsurface cavity with the kinetic energy of the impacting droplet, concluding that the magnitude of the cavity radius is proportional to impact velocity and droplet diameter.3
Buckling Instability Of Crown Sealing, J. O. Marston, Mohammad M. Mansoor, Tadd T. Truscott, S. T. Thoroddsen
Buckling Instability Of Crown Sealing, J. O. Marston, Mohammad M. Mansoor, Tadd T. Truscott, S. T. Thoroddsen
Mechanical and Aerospace Engineering Faculty Publications
Despite the scholarly fascination with water entry of spheres for well over a century,1 we present a new observation, namely, the crown-buckling instability. This instability is characterized by striations appearing near the top of the crown walls just prior to the surface seal, as shown in Fig. 1(a). The crown wall collapses inward due to the pressure differential across the wall created by the moving air in the wake of the sphere and surface tension within the crown. Since the rate of collapse is faster than that at which fluid drains out from the neck region, fluid collects into …