Aerospace Engineering Commons^™

Aerodynamic Design Of A Rectangular Wing In Subsonic Inviscid Flow By Surrogate-Based Optimization, Xiaosong Du, Anand Amrit, Andrew Thelen, Leifur Leifsson, Yu Zhang, Zhong Hua Han, Slawomir Koziel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The paper presents results of aerodynamic design of a rectangular wing in subsonic inviscid flow using surrogate-based local and global search algorithms. The aerodynamic design problem is formulated in Benchmark Cases 3 and 6 developed by the AIAA Applied Aerodynamics Discussion Group. Both involve lift-constrained drag minimization at a Mach number of 0.5 with relatively low lift coefficients (0.2625 and 0.375) with several nonlinear constraints and a small number design variables (up to 15). In this work, the local search is performed using variable-fidelity modelling and output space mapping, whereas the global search is performed using approximation-based surrogates. The paper …

Aerodynamic Design Of The Rae 2822 In Transonic Viscous Flow: Single- And Multi-Objective Optimization Studies, Anand Amrit, Xiaosong Du, Andrew Thelen, Leifur Leifsson, Slawomir Koziel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper addresses a benchmark aerodynamic design problem proposed by the AIAA Aerodynamic Design Optimization Discussion Group: Drag minimization of the RAE 2822 in transonic viscous flow at a fixed lift coefficient with constraints on the pitching moment coefficient and the cross-sectional area. The single-objective optimization (SOO) problem is solved using surrogate-based optimization (SBO) with the surrogates constructed through output space mapping and variable-resolution Reynolds-Averaged Navier-Stokes computational fluid dynamics models. Improving the implementation of our search algorithms enabled us to obtain the SOO optimal design four times faster than in our prior work in terms of CPU time. To explore …

Airfoil Design Under Uncertainty Using Non-Intrusive Polynomial Chaos Theory And Utility Functions, Xiaosong Du, Leifur Leifsson, Slawomir Koziel, Adrian Bekasiewicz

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Fast and accurate airfoil design under uncertainty using non-intrusive polynomial chaos (NIPC) expansions and utility functions is proposed. The NIPC expansions provide a means to efficiently and accurately compute statistical information for a given set of input variables with associated probability distribution. Utility functions provide a way to rigorously formulate the design problem. In this work, these two methods are integrated for the design of airfoil shapes under uncertainty. The proposed approach is illustrated on a numerical example of lift-constrained airfoil drag minimization in transonic viscous flow using the Mach number as an uncertain variable. The results show that compared …

Pareto Ranking Bisection Algorithm For Em-Driven Multi-Objective Design Of Antennas In Highly-Dimensional Parameter Spaces, Adrian Bekasiewicz, Slawomir Koziel, Leifur Leifsson, Xiaosong Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A deterministic technique for fast surrogate-assisted multi-objective design optimization of antennas in highly-dimensional parameters spaces has been discussed. In this two-stage approach, the initial approximation of the Pareto set representing the best compromise between conflicting objectives is obtained using a bisection algorithm which finds new Pareto-optimal designs by dividing the line segments interconnecting previously found optimal points, and executing poll-type search that involves Pareto ranking. The initial Pareto front is generated at the level of the coarsely-discretized EM model of the antenna. In the second stage of the algorithm, the high-fidelity Pareto designs are obtained through optimization of corrected local-approximation …

Molecular Simulation Of Steady-State Evaporation And Condensation: Validity Of The Schrage Relationships, Zhi Liang, Thierry Biben, Pawel Keblinski

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Accuracy, or Even the Validity, of the Schrage Relationships Expressing the Rate of Evaporation and Condensation in Terms of Local Interfacial Thermodynamics Properties and the Mass Accommodation Coefficient is a Subject of Significant Discussion. in This Work, We Carry Out Molecular Dynamics (MD) Simulations of Evaporation and Condensation of Fluid Ar in a Nanochannel. by Adjusting the Temperature Difference, ΔT, between the Evaporating and Condensing Surfaces, We Control the Steady-State Evaporation and Condensation Fluxes (JMD). We Find that Across a Wide ΔT Range Studied, JMD is Always in Excellent Agreement with the Prediction from the Exact Schrage Relationships. Furthermore, …

Design And Modeling Of A Heat Exchanger For Porous Combustor Powered Steam Generators In Automotive Industry, Apratim Dasgupta

Electronic Theses and Dissertations

A major challenge faced by automobile manufacturers is to achieve reduction of particulate emission to acceptable standards, as the emission standards become more and more stringent. One of the ecologically friendly options to reduce emissions is to develop external combustion in a steam engine as a replacement of the internal combustion engine. There are multiple factors, other than pollution that need to be considered for developing a substitute for Internal Combustion Engine, like specific power, throttle response, torque speed curve, fuel consumption and refueling infrastructure. External combustion in a steam engine seems to be a bright idea, for a cleaner …

Implementation Of Optical Interferometry And Spectral Reflectometry For High Fidelity Thin Film Measurements, Armando Arends-Rodriguez

Electronic Theses and Dissertations

An in-house reflectometer/interferometer has been built to investigate the varying curvature and thickness profiles in the contact line region of air, acetone, iso-octane, ethanol, and water on various types of substrates. Light intensity measurements were obtained using our reflectometer/interferomter and then analyzed in MATLAB to produce thickness and curvature profiles. The apparatus is based on the principle of a reflectometer, consisting of different optical elements, probe, light source, and spectrometer. Our reflectometer/interferomter takes measurements in the UV-Vis-IR range (200nm-1000nm). This range is achieved by using a light source that has both a deuterium light (190nm-800nm), a tungsten halogen light (400nm-1100nm), …

Measuring Space Radiation Shielding Effectiveness, Amir Bahadori, Edward Semones, Michael Ewert, James Broyan, Steven Walker

Mathematics & Statistics Faculty Publications

Passive radiation shielding is one strategy to mitigate the problem of space radiation exposure. While space vehicles are constructed largely of aluminum, polyethylene has been demonstrated to have superior shielding characteristics for both galactic cosmic rays and solar particle events due to the high hydrogen content. A method to calculate the shielding effectiveness of a material relative to reference material from Bragg peak measurements performed using energetic heavy charged particles is described. Using accelerated alpha particles at the National Aeronautics and Space Administration Space Radiation Laboratory at Brookhaven National Laboratory, the method is applied to sample tiles from the Heat …

Iris: Deep Space Small Satellite Radio, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

With nanosatellites being used for deep space missions, the need for a unique communications architecture to relay valuable mission data back to NASA’s Deep Space Network (DSN) is vital.

Pearl: Spacecraft Platform, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SDL’s Pearl spacecraft platform delivers the performance, reliability, and mission flexibility needed for demanding small satellite missions. The Pearl platform architecture draws from common sets of components to build 3U, 6U, 12U, and custom sizes with variations in mission capability, parts quality, and radiation tolerance. This flexibility enables our professional staff to develop systems specific to each mission while drawing on a common design to maintain reliability and costs.

Relative Orbital Motion Dynamics With Respect To A Rotating Spacecraft-Fixed Frame, Nicholas Ortolano, David K. Geller, Aaron Avery

Space Dynamics Laboratory Publications

The Clohessy-Wiltshire equations are commonly used to describe the relative orbit motion of two spacecraft in proximity to each other. The relative motion solution provided by these equations is most naturally given in a local-vertical, local horizontal frame. However, if a nearby spacecraft is spinning in a controlled or uncontrolled manner, it may be more convenient to describe the relative orbital motion in the rotating spacecraft-fixed frame. This may be especially true for satellite inspection or approach to a spinning spacecraft. In this paper a set of linear-time-varying differential equations describing the orbital relative motion of two spacecraft as observed …

Sun Radio Interferometer Space Experiment (Sunrise): Tracking Particle Acceleration And Transport In The Inner Heliosphere, Farah Alibay, Justin C. Kasper, T. Joseph W. Lazio

Space Dynamics Laboratory Publications

The authors present a space-based array designed to localize and track the radio emission associated with coronal mass ejections (CMEs) from the Sun. Radio emission from CMEs is a direct tracer of the particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. These questions are among those highlighted in the Solar Decadal Study, e.g., “Discover and characterize fundamental processes that occur both within the heliosphere and throughout the Universe.” Furthermore, CME radio emission is quite strong such that only a relatively small number of antennas is required, and a small …

Real-Time Optimal Trajectory Planning For Orbital Rendezvous, Satellite Inspection, And Docking Based On Convex Optimization, David K. Geller, Nicholas Ortolano, Aaron Avery

Space Dynamics Laboratory Publications

Convex optimization techniques have deterministic convergence properties, are self-starting, i.e., they do not require an initial guess, and have been tested in real-time environments. These optimization techniques are applied to the trajectory planning problem for orbital rendezvous and proximity operations. Spacecraft rendezvous, inspection, and final approach trajectories are considered. Optional trajectory constraints are considered including approach corridors, keep-out zones, and maximum thrust acceleration levels. Two linear dynamics models are investigated: Clohessy-Wiltshire dynamics to describe the relative motion in an LVLH frame, and a new relative orbital motion dynamics model to describe the motion relative to a spinning or uncontrolled spacecraft. …

Nsgt: Software-Defined Nanosatellite Ground Transceiver, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Ground station operators need an affordable, configurable solution to communicate with small satellite radios.

SDL’s software-defined nanosatellite ground transceiver is low cost and highly configurable. It is compatible with a broad range of industry radios, including SDL’s Cadet U and Cadet PLUS.

The nanosatellite ground transceiver can also be used for benchtop testing during spacecraft integration.

Calibration & Testing, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

WHY CALIBRATE?

Once you have designed and built a sensor, it is essential that you calibrate it—especially when it comes to space instruments. Calibration is the only way to translate your raw sensor data into scientific units that can be analyzed for vital information. Science can only occur when you have calibrated data.

In addition, calibration helps you verify that your sensor meets the requirements and helps to identify performance issues under operational conditions before you fly. Thorough calibration testing before deployment significantly increases the probability of mission success.

Cadet: Uhf & Uhf Plus S-Band Radios, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

With the increase in Government-funded and industry small satellites missions, the need for a more robust communication infrastructure is critical for the CubeSat community. As part of the solution, SDL provides the Cadet U and Cadet PLUS radios as powerful communications tools ideal for small satellites. These affordable solutions are available in both UHF (Cadet U) and UHF plus S-Band (Cadet PLUS) configurations. The Cadet radios are compact, power efficient, high data rate transceivers. SDL optimized the design, from the electronics to the modes of operation, for low power consumption.

Multi-Site Simultaneous Time-Resolved Photometry With A Low Cost Electro-Optics System, Forrest Gasdia, Aroh Barjatya, Sergei Bilardi

Publications

Sunlight reflected off of resident space objects can be used as an optical signal for astrometric orbit determination and for deducing geometric information about the object. With the increasing population of small satellites and debris in low Earth orbit, photometry is a powerful tool in operational support of space missions, whether for anomaly resolution or object identification. To accurately determine size, shape, spin rate, status of deployables, or attitude information of an unresolved resident space object, multi-hertz sample rate photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. OSCOM, which stands for Optical …

Variable Structure Feedback Control With Application To Spacecraft With Small Thrust Propulsion Systems, Samuel J. Kitchen-Mckinley

Doctoral Dissertations and Master's Theses

Small spacecrafts requiring small propulsion systems are becoming more popular for low Earth orbit. It is important for these research satellites to have accurate guidance and control systems. Small propulsion systems will also be beneficial for multiple small spacecrafts used future exploration expeditions beyond low Earth orbit. These small spacecrafts benefit from the simplicity of low thrust cold gas propulsion systems. Additionally, large spacecrafts using low thrust, high specific impulse propellants for main propulsion systems, such as ion engines, allow longer and more flexible missions, including Earth orbiting spacecraft and interplanetary spacecraft.

In order to extend the life of future …