Undergraduate Research Abstracts

During the 2014-2015 Academic Year, the Undergraduate Research Institute was able to award a total of 20 Ignite research/scholarship grants and seven Eagle Prize competition grants. For Ignite, projects ranged from focusing on the oral history of veterans to the first student team to fly a rocket to space. Eagle Prize teams will compete in regional and national competitions including the Arizona VEX U Tournament, Association for Unmanned Vehicle Systems International Student Competition, and NASA Human Exploration Rover Challenge.In addition, our students have been conducting independent and team research projects through course-based and student organization opportunities. Linked to their research and scholarship, these students have been active in numerous outreach efforts with regional middle and high schools

Detecting Serial Arcs in Aeronautical Applications Using Inductive Sensors

There is a clear trend in the aircraft industry to use more electrical systems in propulsion and electromechanical and electrohydraulic actuators to comply with environmental sustainability and to improve reliability and maintenance processes. The increase of electrical consumption requires an increase of the rated voltages to supply power to these so called more electrical aircraft (MEA). Unfortunately, this voltage rise, currently up to 540 V$_{dc}$, can lead to ionization processes within the electric wiring due to the lower air density at high altitudes. As a consequence, a degraded insulation can create extremely hazardous events in flight such as arcs between wires (serial) or between wires and fuselage (parallel). Serial arcs in dc bus circuits are specially dangerous for the aircraft operation, so its detection within fractions of seconds is required to ensure a reliable operation. However, during a sustained serial arc the rated current can be passing through air deceiving the protections and avoiding their tripping. In this article, it has been found that arcing introduces high frequency current pulses superimposed to the dc component that can be identified to detect the occurrence of an arc. The frequency components of these pulses depend on the line characteristics and can be detected with inductive sensors. This manuscript also designs and tests a light and inexpensive sensor for arc detection in aircraft applications.This work was supported by Airbus DS internal funding and by the Centro de Desarrollo Tecnologico e Industrial (CDTI) of the Spanish Goverment under Contract CDTI-HV-NET/IDI-20190530. Tests have been done in the high-voltage research and test laboratory (LINEALT) at the University Carlos III of Madri

Electrical power aspects of distributed propulsion systems in turbo-electric powered aircraft

The aerospace industry is currently looking at options for fulfilling the technological development targets set for the next aircraft generations. Conventional engines and aircraft architectures are now at a maturity level which makes the realisation of these targets extremely problematic. Radical solutions seem to be necessary and Electric Distributed Propulsion is the most promising concept for future aviation. Several studies showed that the viability of this novel concept depends on the implementation of a superconducting power network. The particularities of a superconducting power network are described in this study where novel components and new design conditions of these networks are highlighted. Simulink models to estimate the weight of fully superconducting machines have been developed in this research work producing a relatively conservative prediction model compared to the NASA figures which are the only reference available in the literature. A conceptual aircraft design architecture implementing a superconducting secondary electrical power system is also proposed. Depending on the size of the aircraft, and hence the electric load demand, the proposed superconducting architecture proved to be up to three times lighter than the current more electric configurations. The selection of such a configuration will also align with the general tendency towards a superconducting network for the proposed electric distributed propulsion concept. In addition, the hybrid nature of these configurations has also been explored and the potential enhanced role of energy storage mechanisms has been further investigated leading to almost weight neutral but far more flexible aircraft solutions. For the forecast timeframe battery technology seems the only viable choice in terms of energy storage options. The anticipated weight of the Lithium sulphur technology is the most promising for the proposed architectures and for the timeframe under investigation. The whole study is based on products and technologies which are expected to be available on the 2035 timeframe. However, future radical changes in energy storage technologies may be possible but the approach used in this study can be readily adapted to meet such changes

Aerial applications dispersal systems control requirements study

Performance deficiencies in aerial liquid and dry dispersal systems are identified. Five control system concepts are explored: (1) end of field on/off control; (2) manual control of particle size and application rate from the aircraft; (3) manual control of deposit rate on the field; (4) automatic alarm and shut-off control; and (5) fully automatic control. Operational aspects of the concepts and specifications for improved control configurations are discussed in detail. A research plan to provide the technology needed to develop the proposed improvements is presented along with a flight program to verify the benefits achieved

Study of advanced fuel system concepts for commercial aircraft and engines

The impact on a commercial transport aircraft of using fuels which have relaxed property limits relative to current commercial jet fuel was assessed. The methodology of the study is outlined, fuel properties are discussed, and the effect of the relaxation of fuel properties analyzed. Advanced fuel system component designs that permit the satisfactory use of fuel with the candidate relaxed properties in the subject aircraft are described. The two fuel properties considered in detail are freezing point and thermal stability. Three candidate fuel system concepts were selected and evaluated in terms of performance, cost, weight, safety, and maintainability. A fuel system that incorporates insulation and electrical heating elements on fuel tank lower surfaces was found to be most cost effective for the long term

Effectiveness evaluation of STOL transport operations (phase 2)

A computer simulation program which models a commercial short-haul aircraft operating in the civil air system was developed. The purpose of the program is to evaluate the effect of a given aircraft avionics capability on the ability of the aircraft to perform on-time carrier operations. The program outputs consist primarily of those quantities which can be used to determine direct operating costs. These include: (1) schedule reliability or delays, (2) repairs/replacements, (3) fuel consumption, and (4) cancellations. More comprehensive models of the terminal area environment were added and a simulation of an existing airline operation was conducted to obtain a form of model verification. The capability of the program to provide comparative results (sensitivity analysis) was then demonstrated by modifying the aircraft avionics capability for additional computer simulations

Challenges of Implementing Automatic Dependent Surveillance Broadcast in the Nextgen Air Traffic Management System

The Federal Aviation Administration is in the process of replacing the current Air Traffic Management (ATM) system with a new system known as NextGen. Automatic Dependent Surveillance-Broadcast (ADS-B) is the aircraft surveillance protocol currently being introduced as a part of the NextGen system deployment. The evolution of ADS-B spans more than two decades, with development focused primarily on increasing the capacity of the Air Traffic Control (ATC) system and reducing operational costs. Security of the ADS-B communications network has not been a high priority, and the inherent lack of security measures in the ADS-B protocol has come under increasing scrutiny as the NextGen ADS-B implementation deadline draws near. The research conducted in this thesis summarizes the ADS-B security vulnerabilities that have been under recent study. Thereafter, we survey both the theoretical and practical efforts which have been conducted concerning these issues, and review possible security solutions. We create a classification of the ADS-B security solutions considered and provide a ranking of the potential solutions. Finally, we discuss the most compatible approaches available, given the constraints of the current ADS-B communications system and protocol

REDUCING NAVAL FOSSIL FUEL CONSUMPTION AT SEA IN THE 21ST CENTURY

Climate change negatively impacts the Navy's ability to conduct its missions and represents a serious threat to the safety, sovereignty, and future prosperity of the United States. In his Executive Order 14008 dated 27 January 2021, President Joe Biden remarked that current climate considerations are essential to U.S. foreign policy and national security. The Department of Defense is one of the largest single consumers of fossil fuel in the United States. For example, in 2020 the Defense Logistics Agency (DLA) procured over $3.3 billion in fuel for the Navy. It will be the view in this thesis that the motivation and the means exist today, more so than any other point in the Navy's history, to decrease fossil fuel use while increasing operational readiness, and that Navy surface small-combatant ships currently consume more fossil fuel in their daily operations than would otherwise be permitted through the implementation of certain fuel conservation technologies. That is, by updating the fleet the Navy can reduce fossil fuel use and carbon emissions.Lieutenant Commander, United States NavyLieutenant Commander, United States NavyApproved for public release. Distribution is unlimited

The Effects Of Chemical Modification And Layering On Properties Of Woven And Nonwoven Kenaf Fiber Reinforced Epoxy Composites

The great potential of kenaf fiber combined with the new structure of woven and nonwoven fiber mat were reinforced in the epoxy resin by hand lay-up process. The design of stacking combination with different layering pattern of woven and nonwoven as a tri-layer composites was studied. Potensi tinggi gentian kenaf digabungkan dengan struktur baru tikar gentian anyaman dan bukan anyaman diperkuatkan dengan resin epoksi melalui proses ‘hand lay-up’. Reka bentuk kombinasi susunan dengan corak lapisan yang berbeza daripada anyaman dan bukan anyaman sebagai komposit tiga lapisan telah dikaji