Engineering Commons^™

Low-Erosion Nozzle Materials For Long-Duration Hybrid Rocket Burns, Russell S. Babb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid rocket systems, which employ a solid fuel grain and a liquid oxidizer, are a low-cost and environmentally friendly alternative to traditional rocket systems. However, hybrid rockets suffer from an increased nozzle throat erosion rate, which impacts motor performance and reliability. To address this issue several materials and low-erosion nozzle configurations were tested. The results of the testing campaign produced a nozzle that reduce the throat erosion rate five-fold.

Control And Stability Of Upper Stage Launch Vehicle With Hybrid Arc-Ignition Attitude Control System, Steven Russell Bennett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah State University Propulsion Research Laboratory (USUPRL) has recently made significant developments in the area of hybrid rocket systems. This type of propulsion system incorporates a solid fuel and a gas or liquid oxidizer. Hybrid rocket systems are known for their inherent safety, reliability, and restart capability. Over the last several years, the USUPRL has successfully built and tested a hybrid rocket system comprising acrylonitrile butadiene styrene (ABS) plastic and gaseous oxygen (GOX). The system was demonstrated to be fully functional during ground, vacuum, and sub-orbital flight testing. Continuing forward, the USUPRL endeavors to extend the capabilities of this …

Reconstruction Of Attenuated Hybrid Rocket Motor Chamber Pressure Signals Using Maximum Likelihood Estimation And Optimal Deconvolution, Evan M. Zelesnik

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Chamber pressure, as it develops during rocket combustion, strongly correlates with many of the internal motor ballistics, including combustion stability, fuel regression rate, and mass flow. Chamber pressure is also an essential measurement for calculating achieved thrust coefficient and characteristic velocity. Due to the combustion environment hostility, sensing chamber pressure with high-fidelity presents a difficult measurement problem, especially for solid and hybrid rocket systems where combustion by-products contain high amounts of carbon and other sooty materials. These contaminants tend to deposit within the pneumatic tubing used to transmit pressure oscillations from the thrust chamber to the sensing transducer. Partially clogged …

Throttleable Gox/Abs Launch Assist Hybrid Rocket Motor For Small Scale Air Launch Platform, Zachary S. Spurrier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability for an aircraft-based launch platform to place an orbital payload onto a nominal launch trajectory at a higher energy state -- altitude, velocity, flight path angle, and azimuth --using highly-efficient air breathing propulsion instead of a much lower-efficiency rocket system, offers the potential for a significantly smaller launch vehicle. An airborne platform also provides the ability to launch from multiple locations and allows for significantly increased "system responsiveness." The NASA Armstrong Flight Research Center’s Towed Glider Air-Launch System (TGALS) is a small-scale flight research project investigating the feasibility for a remotely-piloted, towed, glider system to act as a …

High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Sean D. Walker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid Rockets are popular in the aerospace industry due to their storage safety, simplicity, and controllability during rocket motor burn. However, they produce fuel regression rates typically 25% lower than solid fuel motors of the same thrust level. These lowered regression rates produce unacceptably high oxidizer-to-fuel (O/F) ratios that produce a potential for motor instability, nozzle erosion, and reduced motor duty cycles. To achieve O/F ratios that produce acceptable combustion charactersitics, traditional cylindrical fuel ports are fabricated with very long length-to-diameter ratios to increase the total burning area. these high aspect ratios produce further reduced fuel regression rate and trust …

Direct Electrical Arc Ignition Of Hybrid Rocket Motors, Michael I. Judson Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid rockets motors provide distinct safety advantages when compared to traditional liquid or solid propellant systems, due to the inherent stability and relative inertness of the propellants prior to established combustion. As a result of this inherent propellant stability, hybrid motors have historically proven difficult to ignite. State of the art hybrid igniter designs continue to require solid or liquid reactants distinct from the main propellants. These ignition methods however, reintroduce to the hybrid propulsion system the safety and complexity disadvantages associated with traditional liquid or solid propellants. The results of this study demonstrate the feasibility of a novel direct …

Development Of The Multiple Use Plug Hybrid For Nanosats (Muphyn) Miniature Thruster, Shannon Dean Eilers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Multiple Use Plug Hybrid for Nanosats (MUPHyN) prototype thruster incorporates solutions to several major challenges that have traditionally limited the deployment of chemical propulsion systems on small spacecraft. The MUPHyN thruster offers several features that are uniquely suited for small satellite applications. These features include 1) a non-explosive ignition system, 2) non-mechanical thrust vectoring using secondary fluid injection on an aerospike nozzle cooled with the oxidizer flow, 3) a non-toxic, chemically-stable combination of liquid and inert solid propellants, 4) a compact form factor enabled by the direct digital manufacture of the inert solid fuel grain. Hybrid rocket motors provide …

Design And Testing Of Digitally Manufactured Paraffin Acrylonitrile-Butadiene-Styrene Hybrid Rocket Motors, Jonathan M. Mcculley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid motors that employ non-toxic, non-explosive components with a liquid oxidizer and a solid hydrocarbon fuel grain have inherently safe operating characteristics. The oxidizer is blown though the solid fuel where it is combusted through a nozzle to produce thrust. This research investigated the combination of Acrylonitrile-butadiene-styrene impregnated with paraffin wax as the solid fuel component burned with nitrous oxide. The paraffin provides an enhanced regression rate over ABS; however, it lacks structural integrity and combustion efficiency. Multiple fuel grains with various ABS-to-Paraffin mass ratios were fabricated and burned with nitrous oxide. Analytical predictions for end-to-end motor performance and fuel …

Catalytic Decomposition Of Nitrous Oxide Monopropellant For Hybrid Motor Ignition, Matthew D. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrous oxide (N₂O), a commonly-used industrial gas, is also often used as a rocket motor oxidizer. It has been used in both hybrid rocket motors (using a solid fuel and a liquid oxidizer) and liquid rocket engines (using liquid fuel and oxidizer).

As a liquid form, nitrous oxide is highly stable, but in vapor form it can be decomposed, releasing large amounts of heat as it dissociates into nitrogen and oxygen. This project investigates using the energy from decomposing nitrous oxide to ignite a hybrid or liquid rocket. Such a system would be practical in rocket …

Closed-Loop Thrust And Pressure Profile Throttling Of A Nitrous Oxide/Hydroxyl-Terminated Polybutadiene Hybrid Rocket Motor, Zachary W. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid motors that employ non-toxic, non-explosive components with a liquid oxidizer and a solid hydrocarbon fuel grain have inherently safe operating characteristics. The inherent safety of hybrid rocket motors offers the potential to greatly reduce overall operating costs. Another key advantage of hybrid rocket motors is the potential for in-flight shutdown, restart, and throttle by controlling the pressure drop between the oxidizer tank and the injector. This research designed, developed, and ground tested a closed-loop throttle controller for a hybrid rocket motor using nitrous oxide and hydroxyl-terminated polybutadiene as propellants. The research simultaneously developed closed-loop throttle algorithms and lab scale …

Effect Of Deposition From Static Rocket Test Fires On Corn And Alfalfa, Scout Mendenhall

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A greenhouse study was conducted to determine the effects of deposition from static rocket test fires on corn and alfalfa. Seeds were germinated in a wide concentration range of depositional material, called test fire soil (TFS). Additionally, the impact of chloride and aluminum, two major components of test fire soil, on germination was also evaluated. Furthermore, plants were grown in packed columns and exposed to test fire soil, either in the root zone or on foliage. Tissue was weighed and analyzed to compare biomass production and plant composition.

Corn and alfalfa exposed to test fire soil in the root zone …