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Aerospace Engineering Commons

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Articles 1 - 6 of 6

Full-Text Articles in Aerospace Engineering

Optimal Sizing And Control Of Hybrid Rocket Vehicles, Srija Ryakam Dec 2021

Optimal Sizing And Control Of Hybrid Rocket Vehicles, Srija Ryakam

Doctoral Dissertations and Master's Theses

In the present work, a genetic algorithm is used to optimize a hybrid rocket engine in order to minimize the propellant required for a specific mission. In a hybrid rocket engine, the mass flow rate of the oxidizer can be throttled to enhance the performance of the rocket. First, an analysis of the internal ballistics and the ascent trajectory has been carried out for different mass flow rates of the oxidizer as a function of time, for a fixed amount of oxidizer, in order to study the effect of throttling. Two equivalent problems are considered: in the first problem the …


Active Control Of Coherent Structures In An Axisymmetric Jet, Michael Marques Goncalves Aug 2021

Active Control Of Coherent Structures In An Axisymmetric Jet, Michael Marques Goncalves

Doctoral Dissertations and Master's Theses

The primary objective of this work is to develop high-fidelity simulation model for jet noise control predictions and quantify the sound reduction when an external source frequency mode excitation is imposed on the jet flow. Whereas passive approaches using mixing devices, such as chevrons, have been shown to reduce low-frequency noise in jet engines, such approaches incur a performance penalty since they result in a reduced thrust. To avoid a performance penalty in reducing jet noise, the current work investigates a open-loop active noise control (ANC) system that utilizes a unsteady microjet actuator on the nozzle lip in the downstream …


Background Flow Influence On Impulsive Jet-Driven Micro Droplet Dispersal, Vaishak Thiruvenkitam Aug 2021

Background Flow Influence On Impulsive Jet-Driven Micro Droplet Dispersal, Vaishak Thiruvenkitam

Doctoral Dissertations and Master's Theses

Accurately predicting the airborne spread of infectious diseases is crucial in controlling the COVID­19 pandemic today. Studies have shown the spread of expiratory droplets depends on ambient thermodynamic conditions and flow properties of the jet emitted by the activity. However, the droplet spread in conditions of background flow is not yet comprehensively understood. This study uses the Eulerian­-Lagrangian model with k−ω turbulence modelling to simulate spread of particles and study the factors affecting it in a closed environment with a background flow. Respiratory activities are modeled as a non-­isothermal jet of air with droplets suspended in them in a predetermined …


Design And Flight-Path Simulation Of A Dynamic-Soaring Uav, Gladston Joseph Jul 2021

Design And Flight-Path Simulation Of A Dynamic-Soaring Uav, Gladston Joseph

Doctoral Dissertations and Master's Theses

We address the development of a dynamic-soaring capable unmanned aerial vehicle (UAV) optimized for long-duration flight with no on-board power consumption. The UAV’s aerodynamic properties are captured with the integration of variable fidelity aerodynamic analyses. In addition to this, a 6 degree-of-freedom flight simulation environment is designed to include the effects of atmospheric wind conditions. A simple flight control system aids in the development of the dynamic soaring maneuver. A modular design paradigm is adopted for the aircraft dynamics model, which makes it conducive to use the same environment to simulate other aircraft models. Multiple wind-shear models are synthesized to …


Folding Methodology For Flexible Aircraft Interiors, Aditya Venkatesh, Fengfeng (Jeff) Xi, Joon Chung Jan 2021

Folding Methodology For Flexible Aircraft Interiors, Aditya Venkatesh, Fengfeng (Jeff) Xi, Joon Chung

International Journal of Aviation, Aeronautics, and Aerospace

This paper establishes a general furniture folding methodology that is aimed at flexible aircraft cabin interiors. This methodology will allow users to modify existing furniture pieces to their liking and thereby customizing their overall travel experience. The folding methodology also includes a process to quantify the transformation of the furniture pieces. This paper also introduces two design concepts called Open-on-Demand and Reconfiguration to allow passengers to modify an otherwise rigid cabin. The advantages of the multi-functional space saving furniture pieces are also illustrated in this paper. While the general folding methodology was developed for aircraft interiors, it can be adapted …


Remote Pilot Situational Awareness With Augmented Reality Glasses: An Observational Field Study, Jeffery Coleman, David Thirtyacre Jan 2021

Remote Pilot Situational Awareness With Augmented Reality Glasses: An Observational Field Study, Jeffery Coleman, David Thirtyacre

International Journal of Aviation, Aeronautics, and Aerospace

With the use of small unmanned aerial systems (sUAS) proliferating throughout industry and public safety, it is imperative to ensure safety of flight. The Federal Aviation Administration (FAA) published regulations for commercial use of sUAS in 2016 and included the requirement to maintain visual line-of-sight with the aircraft at all times. However, due to the nature of the sUAS ground control stations (GCS), remote pilots time-share between observing the aircraft and interacting with the display on the GCS. Time-sharing between the aircraft and GCS can be seen as similar to the cross-check a pilot uses when flying a manned aircraft. …