Analysis of Electrode Behavior for Electric Solid Propellant (ESP) Tactical Rocket

Motor Development by

Victoria Van

An Honors Capstone submitted in partial fulfillment of the requirements

for the Honors Diploma

The Honors College

The University of Alabama in Huntsville

Spring 2017

Honors Capstone Director: Dr. Patrick G. Taylor U.S. Army

Aviation and Missile Research, Development, and Engineering Center (AMRDEC) Weapons Development and Integration Directorate (WDI)

AMRDEC Missile Power Technology Area Lead Electronics Engineer

a&bw 811 51 1 L Student (signature) Date TAYLOR,pATRICK.GLEN. 1 : " D W U W ~ " Y T A Y L C ' R PATR'LKGLEN 1 W 1 3 5 5

ON -US o:U S Garanmmt e u = b O ou=PK' ourUSA

29048 1 356 cn=TAYLMI PATR'CKGLEN 12801013% ~ s l a Z O I S M I I Z ~ ~ ~ ~ ~ B - O S W 0811212016

Director (signature) Date

TAYLOR. pATRICK.GLEN. 1 WWbugnedby TAYLOR PATRICKGLEN 1280181353 DN -US 0-U S G a r m m n l ou=bD DU.PKI ourUSA

290481 356 -TAYLOR PATRICKGLEN 12W1111355 Dee 2016 w 12 14 M07.OSW

0811 21201 6

Date

I

Property rights resid8with the Honors College. University ofAlabo~na in Huntsville, Huntsville. AL

US. ARMY 1 > .- - ----m -I:* -

i BEHAVIOR FOR ELECTRIC SOLID PROPELLANT (ESP) TACTICAL

ROCKET MOTOR DEVELOPMENT

Victoria Van

University of Alabama in Huntsville 27 July 2016

Weapons Development and Integration Directorate

Aviation and Missile Research,, Development, and Engineering B Center

Mentor: Dr. Patrick G. Taylor

Unclassified i

Edited for the University of Alabama in Huntsville Honors Capstone

REPORT DOCUMENTATION PAGE

6. AUTHOR@)

Victoria Van, Patrick G . Taylor, Christina A. Blankenship, Alyson D.

Form Approved OMB No. 074-0188

I

Public reporting burden for thls collection of lnformatlon is estimated to average I hour per response, Including the time for reviewing instnrctlons, searching existing data sources. gathering and malntalning the data needed, and compietlng and reviewing this collection of information. Send comments regarding thls burden estimate or any other aspect of this collection of information, including suggestions for reduclng thls burden to Washington Headquarters Services, Directorate for information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Papemork Reduction Project (07044188). Washington, DC 20503

Miller.

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

Commander, U. S. Army Research, Development, and

3. REPORT TYPE AND DATES COVERED 1 .AGENCY USE ONLY

Engineering Command ATTN: RDMR-WDP-P Redstone Arsenal, AL 35898-5000

2. REPORT DATE

July 20 16

8. PERFORMING ORGANIZATION REPORT NUMBER

4. TITLE AND SUBTITLE

Analysis of Electrode Behavior for Electric Solid Propellant (ESP) Tactical Rocket Motor Development

TR- RDMR-XX- 1 6-00

5. FUNDING NUMBERS

9. SPONSORING 1 MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING I MONITORING AGENCY REPORT NUMBER

11. SUPPLEMENTARY NOTES 1

Unclassified

12a. DISTRIBUTION I AVAILABILITY STATEMENT

I

13. ABSTRACT (Maximum 200 Words)

This report details the study of electrode behavior in terms of its application to Electric Solid Propellant (ESP). Based on an analysis of the benefits of electrically stimulated activation as opposed to the current method of pyrotechnics, the development of electrically responsive energetic materials allows for warfighters and personnel to execute instantaneous ignition and control the burn rate of the rocket propellant. Furthermore, issues from previous attempts of ESP efforts are noted and taken into consideration during this research process. The initial focus of this investigation is on various electrode materials and their effects on the electric field.

12b. DISTRIBUTION CODE

14. SUBJECT TERMS

1 NCI ,qSSlFlF.D 1NCI.ASSIFIED I INCLASSIFIED I SAR I NSN 7540-0 1-280-5500 Standard Form 298 (Rev. 2-89)

Prescr~bed by ANSI Std 239-1 8 298-102

15. NUMBER OF PAGES

44

16. PRICE CODE

20. LIMITATION OF ABSTRACT 19. SECURITY CLASSIFICATION OF ABSTRACT

17. SECURITY CLASSIFICATION OF REPORT

18. SECURITY CLASSIFICATION OF THIS PAGE

TABLE OF CONTENTS

I . ABSTRACT ........................................................................................................................... 1

I1 . INTRODUCTION ................................................................................................................. 2

A . History ................................................................................................................................ 2

B . Current Method vs . Proposed Method ........................................................................... 3

......................................................... C . High Performance Electrical Propellant (HIPEP) 5

D . Electrode Basics ................................................................................................................ 8

...................................................................................................................... I11 . EXPERIMENT 9

A . Test Objective .................................................................................................................... 9

B . Experimental Equipment ................................................................................................. 9

C . Procedures ....................................................................................................................... 10

....................................................................................................... IV . DATA AND RESULTS 14

.............................................................. A . Electrode Geometry Effect on Electric Fields 14

B . Electrode Material .......................................................................................................... 15

C . Electrode Options ............................................................................................................ 17

.................................................................................................................. V . CONCLUSIONS 19

VI . FUTURE WORK ................................................................................................................ 20

................................................................................................................... CQL EXPERIENCE 22

....................................................................................................... ACKNOWLEDGEMENTS 24

............................................ LIST OF ABBREVIATIONS. ACRONYMS. AND SYMBOLS 25

............................................................................................................................ REFERENCES 27

APPENDIX A ............................................................................................................................... A

APPENDIX B ................................................................................................................................ B

............................................................................................................................... APPENDIX C C

iii

LIST OF ILLUSTRATIONS

Figure . Title

Figure 1 . DSSP Electrically Controlled Energetic Materials (ECEMs) ................................ 1

.......................................................................................... Figure 2 . ASPEN Ignition Sequence 2

Figure 3 . Current Ignition Method (Squib) .............................................................................. 3

.......................................................................... Figure 4 . Proposed Method of Ignition (ESP) 4

........................................................................................ Figure 5 . DSSP Proof-of-Concept [I] 5

Figure 6 . Experimental Equipment for Measuring Electric Fields .................................. 10

Figure 7 . Electrode Configuration for Measuring Electric Fields Setup ............................. 11

Figure 8 . Example of Copper Electrodes Setup with EMF Meter ....................................... 12

Figure 9 . Electrode Geometry Effect on Electric Fields [6] .................................................. 15

Figure 10 . Heavy Wall Test Motor .......................................................................................... 20

..................................................... Figure 11 . Motor Concept with Electrode Configuration 21

LIST OF TABLES

Table . Title . Page

Table 1 . ASPEN'S 0.47 Second Ignition Sequence Steps ......................................................... 2

Table 2 . Tactical Propulsion Material Hazards [3] ................................................................. 5

...................................................................................... Table 3 . HAN Formulation Matrix [4] 7

Table 5 . Electrode Materials [7] .............................................................................................. 16

Table 6 . Compilation of Electrode Options from Supply Companies ............................... 18

I. ABSTRACT

This report details the study of electrode behavior in terms of its application to Electric

Solid Propellant (ESP). Based on an analysis of the benefits of electrically stimulated activation

as opposed to the current method of pyrotechnics, the development of electrically responsive

energetic materials allows for warfighters and personnel to execute instantaneous ignition and

control the bum rate of the rocket propellant. Furthermore, issues from previous attempts of ESP

efforts are noted and taken into consideration during this research process. The initial focus of

this investigation is on various electrode materials and their effects on the electric field.

11. INTRODUCTION

A. History

In 1996. the U.S. Air Force began funding for environmentally-benign azide-free

automobile Air Bag Inflator Propellants (ABIP). ET Materials. LLC project lead Art Katzakian

and his research group obtained a patent that year for their formulation for their ABIP.

Afterwards, Katzakian's team formulated an ammonium-nitrate based electrically controlled

extinguishable solid propellant (ECESP) called ASPEN [I]

Table 1. ASPEN'S 0.47 Second Ignition Sequence Steps

A desire for a greater I,,, or specific impulse, called for improvements, thus leading to the

development of High Performance Electrical Propellant (HIPEP) [2].

Impulse Formula

Impulse = Force x time

I = FA^

In 2005, W. Sawka obtained rights to the ECESP HIPEP formulation and started Digital

Solid State Propulsion, Inc. (DSSP) in order to continue researching propellant. The motivation

for a green ESP is due to the need of a low-hazard, safer h e l source alternative for tactical rocket

motors [ I ] .

B. Current Method vs. Proposed Method

The current method for rocket propellant activation involves a multi-step ignition train.

As shown in Figure 3, the squib (initially represented by the blue curve which turns red) is

ignited, which in turn ignites the ignitor charge (black scribbles). With extreme heat applied in

the combustion chamber. the propellant closest to the chamber is activated, thus, causing a chain

reaction.

Current Method: Squib (Pyrotechnic) Multi-Step Ignition Train (Current Igniters)

Figure 3. Current Ignition Method (Squib)

This pyrotechnic propulsion method also releases hazardous emissions, like lead, that are

harmful to warfighters, Department of Defense (DoD) personnel, and the environment. The

emerging electrical stimulus propulsion technology and a desire for an environmentally kind

alternative fuel source motivated the U.S. Army to seek an improved method for launching

rocket systems. This sparked the investigation of the ESP single step ignition train. Shown in

Figure 4 below, this future method for igniting rocket motors involves sending an electric

current, activating the core which burns from inside out. The single step ignition train decreases

the chances of risk by eliminating the need for many reactions. Unlike a squib, the electric

current sent through embedded electrodes can be activated and discontinued, permitting control

of turning the propellant on and off instantly and at a specific burn rate. The simultaneous and

immediate activation of ESP also promote the electrically responsive energetic material

technology as an ideal alternative to the current multi-step ignition train method.

Proposed Method: Electrical Stimulus

Single Step Ignition Train (Future Igniters)

Figure 4. Proposed Method of Ignition (ESP)

Furthermore, the ESP is environmentally-benign due to its lack of toxic byproducts. The

present tactical rocket propulsion system fuel source exposes warfighters and personnel to

respiratory and reproductive hazards, which are listed below in Table 2 [3].

Table 2. Tactical Propulsion Material Hazards [3]

Family or Class

Environmental Risk, Personnel Examples Air (A)-Ground(G1-Water(W1 Toxicitv Nitramines RDX, HMX, CL20 G, W

Nitrate Esters TMETN, DEGDN, NG, BTTN, BuNENA G, W

Heavy Metals Organo-lead compounds, Cr G, W

Perchlorates Ammonium Perchlorate A, G, W ppp

ADN Unknown Dinitramides

Aziridines

lsocyanates

Unlike traditional propellants' hazardous emissions, the electrically stimulated propellant

emits water, steam. and inert materials. Past concerns about the safety of HAN have largely

been dismissed through current efforts. HAN is now seen as an environmentally suitable

material for propellant formulation [4].

Figure 5. DSSP Proof-of-Concept [1]

C. High Performance Electrical Propellant (HIPEP)

Currently, DSSP and the U.S. Army are conducting tests to determine the viability of

ESP as an alternative fhel source for rocket propulsion. This progresses the efforts to switch

from a pyrotechnic to an electrically stimulated ignition. DSSP has been reformulating HIPEPS.

The baseline propellant primer's performance is not affected by electrostatic shock, impact, or

friction. Instead, HLPEP can only be trigger by electrical power.

Previously, Armament Research, Development, and Engineering Center (ARDEC)

researchers at Picatinny Arsenal conducted tests on DSSP's electric solid-state propellant. DSSP

designed an energetic compound based on hydroxylammonium nitrate (HAN) which has the

viscosity of a liquid but can become solid when heated. The HIPEP formulation was intended

for gun propellant, and research was conducted by ARDEC chemists and engineers from a

chemical analysis standpoint. However, from the experiments, several issues occurred. During

thermal stability tests, the energetic materials were deemed unstable and released too much gas.

At high temperatures, the material's mass decreased, and the propellant's shape lost form.

Therefore, the initial application for gun tank igniters was not successful.

In 2013, ARDEC switched to internal funding to research electrically stimulated

propulsion technology. Picatinny engineers modified HAN-based formulation in order to obtain

an energetic material ideal for weapon integration. The new application was targeted for rocket

propellant due to more promising HIPEP test results. The reformulation improved thermal

stability, but still yielded loss of mass and did not ignite in a desired manner. In the report

"Development of Electrically Responsive Energetic Materials," the modified formula was not

performing up to standards, so plans for future efforts were proposed [4].

The formulation matrix is displayed below in Table 3 and details the versions of

electrically ignition material. Some currently fielded propellants types Ammonium Perchlorate

(AP), Hydroxyl-terminated Polybutadiene (HTPB), Glycidol Azide Propellant (GAP), and

Nitrocellulose (NC) were modified to generate electrical responses.

Table 3. HAN Formulation Matrix [4]

Tab

Existing

Existing (Mod)

Existing (Mod)

Existing (Mod)

Existing

Existing (Mod)

Novel

3 Abbreviations:

.-a,.. b 7

111

. . Major Ingredients - ..- . ..

AP, HTPB

AP, HTPB, 0.5% - 10% conductive additive

AP, HTBP, 10.0% NQ

AP, HTPB, 10.0% TAGN

AP, GAP

AP, GAP, 1 .O% conductive additive

1 1.6%NC, 50% tricyanomethanide IL 1

1 1.6%NC, 50% tricyanomethanide IL 2

13.15%NC, 10% tetracyanoatocobaltate IL

13.15%NC, 30% tetracyanoatocobaltate IL

13.15%NC, 10% tetrachloroferrate IL

13.15%NC, 25% tetrachloroferrate IL

13.15%NC, 2.5% poly(5-methoxy-2-(3-su1fopropoxy)-1,4- phenylenevinylene)

potassium salt (2 wt. % in water, Sigma-Aldrich)

Mod = Modified

AP = Ammonium Perchlorate

HTPB = Hydroxyl-Terminated Polybutadiene

GAP = Glycidol Azide Propellant

NC = Nitrocellulose

Aviation & Missile Research Development (AMRDEC) plans to continue researching

electrically controlled solid propellants. Beginning during the summer of 201 6, initial stages of

the three-year program involve basic electrode modeling and field pattern behavior. The

timeline of the project is in Appendix A. Information on various electrode materials and possible

prepackaged electrodes are listed in the Appendices as well.

D. Electrode Basics

In this experiment, embedded electrodes will send an electric current through an ESP.

An electrode is a conductor that can be passed positive or negative charge. Electric fields are

regions where an electric charge generates a force. Electromagnetic field (EMF) meter is a

device used to measure electromagnetic fields, but in this experiment, they are used to measure

electric fields [4]. These experimental equipment are to be used for basic electrode modeling

development.

111. EXPERIMENT

A. Test Objective

As detailed in this report, the objective of the basic electrode model development stage is to

research and analyze the behavior of electrodes comprised of various elements in order to

observe the effects of the generated electric fields for the purpose of Electric Solid Propellant

(ESP) application.

B. Experimental Equipment

Although this phase of the development project involves mainly research of electrodes,

their materials, their behavior, and their effects on electric fields, the next stage involves testing

electrode configurations in order to measure the electric field. Equipment for this portion of the

project were gathered.

Electrodes (varied) - copper

DC Power Source

EMF Meter - Lutron EMF-828 (3 Axis EMF Tester)

Test Material (varied)

Two (2) Cables -two alligator clips at one end and BNC connector on other

Two (2) Oscilloscopes

Multimeter - Fluke 87-5 True RMS Industrial Digital Multimeter

Oscilloscopes i

Figure 6. Experimental Equipment for Measuring Electric Fields

C. Procedures

Due to the time limitations of the AMRDEC College Qualified Leaders (CQL) program,

actual experimentation will commence after the program's end. This procedure details the steps

to measure the electric field with the purchased prepackaged electrodes or custom designed

electrodes.

.I DC power I Source r

.. .. . - - IIIIIIIIIIIII

Propellant 1 Test Material 1 I - - - - - - - - - - ; I I

Figure 7 . Electrode ConJiguration for Measuring Electric Fields Setup

Electrode Configuration for Measuring Electric Fields Procedure

1) Clear a tabletop to set up an electrode station. Make sure the DC Power Source is

hnctioning properly.

2) Taking a cable with alligator clips, clip one end to an electrode. Using the second cable

with alligator clips, clip one end to the second electrode. Repeat the steps with the

second cable.

3) Attach to the two open ends of the two cables to the DC Power Source. In the case of

viewing the changing voltage, attach each of the BNC connector ends of the cables to an

oscilloscope. After this step, a cable should go from one oscilloscope to the electrodes.

For each cable, one alligator clip will connect to one electrode, and the other will connect

to the other electrode.

4) To connect the test configuration to the multimeter, first power on the multimeter device,

and place the setting on DC voltage. Attach the alligator clip cables from the multimeter

to the electrodes. Read the voltage measurement on the multimeter display.

5) Obtain the test material and place it between the two electrodes. Allow the electrode-test

material-electrode sandwich rest on a stable surface. Depending on the configuration, the

electrodes may also be inserted into the test material, similar to the setup in Figure 6.

I Copper 1 Electrodes

EMF Meter I

Figure 8. Example of Copper Electrodes Setup with EMF Meter

6) Power on the EMF meter by pressing the power button. The connected EMF meter wand

can be placed or waved near the electrode setup to detect the electric field. In Figure 8.

the EMF Meter is measuring in the x-axis direction, indicated by the "x" at the bottom of

the screen. Note that Figure 8 displays the EMF meter in mGauss, which is measuring

the magnetic field. To switch to electric field settings, set the "Units" option to Tesla.

7) The Lutron EMF-828 offers three (3) coordinate options. Press the "X.Y.Z" button to

switch between the x, y, and z directions.

8) Record the electric field measurement from the value displayed on the EMF Meter. Press

the power button to power off the device.

IV. DATA AND RESULTS

Ultimately, the experimental testing matrix will consist of four factors: electrode

geometry, test material and propellant, electrode type, and size. Electrode geometry describes

the shape of the electrode. The test material is the material between the electrodes, such as air,

wood, rubber, or the propellant. Electrode type may concern the electrode's materials like

copper, silver, and stainless steel. Electrodes also come in various sizes. All of these factors

may contribute to the performance of the HIPEP. Essentially, this phase aims to develop a basic

electrode model.

A. Electrode Geometry Effect on Electric Fields

The collection of images below is provided by Peng et al. in their paper on the effects of

electrode material and configuration on planar resistive switching devices. Their research on

electrode geometry may be applicable in the current ESP program. In Figure 8, the first row of

images show the three (3) electrode geometries: (a) rectangle, (b) circle, and (c) triangle. The

second row shows the electric field's intensity of each electrode geometry. The current-voltage

graph for (g) depicts the switching loop [6 ] .

(a) Rectangle (b) C~rcle

ST0

1

I , : I Triangle Rectangle Circle

Figure 9. Electrode Geometry Eflect on Electric Fields [6]

In Figure 9, the triangle electrodes tend to have the strongest electric fields, indicated by

the red regions. Compared to the triangle electrodes, the rectangle electrodes have a mild

electric field with a yellow region. The circle electrodes are not as pointy as the triangle

electrodes and not parallel like the rectangle electrodes. As a compromise between the flat and

pointy electrode tips, the circle electrode also has red regions where the electric field is stronger,

but they are not as pronounced as the triangle's, which has the most intense electric fields at the

red regions at the tip. Overall, sharp geometric turns cause more powerhl electric fields [6] .

B. Electrode Material

Various electrode materials offer different properties depending on the elements that they

are comprised of. Table 5 shows some of the common electrode materials researched for this

project. Being easily obtained and conductive, copper will be the first electrode material tested.

This first set of copper electrodes will also be custom designed at either the machine shop at the

Electric Propulsion Lab or at a supply company.

Table 4. Electrode Materials [7]

It should be noted that tungsten is not recommended for this project because of its safety

hazards. One of the primary goals of this ESP development project is to formulate a low-toxic or

non-hazardous fuel source. Tungsten is used for gas tungsten arc welding (GTAW), so there are

Material

Gold

Silver 1 AgCl

Copper

Stainless Steel

Tungsten

Graphite and Carbon

Platinum

Titanium

Brass (Copper and Zinc Alloy)

Palladium

Mixed Metal Oxide (MMO)

Notes

Good for recording electrodes ($$$)

Most conductive Very soft High oxidation resistance Strengthened with copper or other alloys High signal to noise ratio

Conductive Stronger than Ag Easily oxidizes

Used in phantoms

Used in gas tungsten arc welding (GTAW) Flatter tips have lower pressure and arc velocities and plasma temperature

uniformly distributed Electrode potential +0.5 V and 1.5 V corrodes 6 192 F Melting Point

Soft Very high sublimation temperature so resistant to high-temperature arcs Corrosion resistant Fine graphite grains high wear resistance

($$$)

Resists erosion & corrosion High contact resistance films in organic vapors ($$$)

High strengthlweight ratio Corrosion resistance

Small tubular electrodes Less wear resistance compared to tungsten & copper Less conductive than copper

Resists erosion and corrosion ($$$)

Oxide coat over inert metal or carbon core

many types of electrode tips already used for this type of electrode. Two-percent (2%) thoriated

tungsten electrodes are commonly used, but they are radioactive. The most commonly used non-

radioactive tungsten is 2%-Lanthanated, but supply companies still label then with hazard

warnings due to having carcinogenic properties [8]. For more details of each electrode material

listed in Table 5, see Appendix B.

C. Electrode Options

Due to government contracts making the purchasing process slightly more efficient,

electrodes will preferably be purchased from Cole-Parmer, Omega, Fisher Science, and MSC

Industrial Supply Co. In the online catalogs of the previously listed companies, the most

common options were silver electrodes. The supply catalogue companies offered mainly

reference types of electrodes and ones typically used in electrochemical lab environments for

aqueous solutions. An electrode is anything that passes positive or negative charge, so even rods

of copper could hnction as electrodes for the purposes of this lab. For more electrode options

from the online companies, see Appendix C.

Table 5. Compilation of Electrode Options from Supply Companies

I I Dinmctcr-

'

Electrode Electroclc Material & , Othcr , /S i ze I

I

I'latinum or stainless steel. ouler- stainless

stecl

MICRO PROBE INC CONCENTRIC ELECTRODE, - - PLATINUM

Hazardous Miller Electric Tungsten $57.90 1 material; May Electrode, 3/32 In D, 7 In L,

'

Pack of 10 3132x7 in. cause cancer but PKl 0 (Grainger) does NOT

contain Thorium

Fisher ScientificTM accumetTM Silver $165.24 -

Glass Body Ag/AgCl Reference $28 1.84 - (Ag/AgCI)

o0 to +I 1 O°C Electrodes - Mercury-Free Each

Tungsten (2% Lanthanatec

V. CONCLUSIONS

This report details the initial stage of a three-year project conducted by the WDI Electric

Propulsion Lab that aims to develop electrically responsive energetic materials for tactical rocket

motor propulsion. Several issues with the current method of rocket motor propulsion prompt for

the development of an ESP fitting the criteria. As of July 2016, U.S. Army missiles still rely on

a multi-step ignition train. This pyrotechnic technology involves igniting a squib and calls for a

chain reaction to occur. More steps allow for more errors to occur during the procedure.

Additionally, respiratory hazardous emissions are released which harm nearby personnel and the

environment. ESP addresses environmental concerns due to its lack of toxic side effects.

The proposed method of a single-step ignition train requires an electrical current to

stimulate the ignition through the rocket motor core. The advantages of this ESP technology

include control over ignition and bum rate, safer setup due to the process only involving a single

step, and the ,immediate response. Heat, electrostatic discharge, and sparking do not affect the

DSSP ESP, which is only ignitable with electrical power. The U.S. Army is motivated to pursue

this technology for their tactical rocket motor propulsion systems for environmental and health

benefits as well. The DSSP ESP formulation does not emit hazardous chemicals, like lead, that

may harm DoD personnel, soldiers, and the environment.

While ARDEC's research aimed to develop an ESP for guns and focused on the chemical

properties, the WDI project focuses on both the chemical and electrical standpoints for rocket

motor application.

VI. FUTURE WORK

Since this is the first phase of the ESP development program, much of the future work for

this time frame involves collecting data of how specific electrodes and their properties affect the

electric field. Electrode options from supply companies require more time allotted for ensuring

availability from the distributor, packaging, shipping, and paperwork processing. As a result,

prepackaged electrodes will arrive after the conclusion of the summer program. The next readily

available electrodes are custom designed copper electrodes. Different dielectric or test materials

will be placed between the electrodes for testing. Possible materials include air, wood, rubber.

and plastic. The HIPEP formulation will be used at a later stage. Essentially, the goal for the

basic electrode model development phase is to develop a mathematical model of how electrodes

behave.

In later testing phases, electrodes configuration tests will be conducted on the heavy wall

test motor shown below. Used for large scale testing, this device is used to determine whether

the ESP is suitable for tactical rocket motor use. If successful, the flight weight simulation motor

testing will be conducted, followed by prototype flight motor large scale testing.

I Figure 10. Heavy Wall Test Motor

Actual ESP rocket propellant will also be used in later phases for testing the electrodes.

The proposed setup for rocket motor propellant chamber is shown below in Figure 11.

Theoretically, an electric current will go through the embedded ignition electrodes, thus igniting

the continuous propellant grain. Without demolishing the outer casing, the thrust generated will

exit through the nozzle, allowing the rocket, weapon, or missile to be propelled.

Continuous Propellant

Grain

Electrodes

Highly insensitive, high performance minimum signature formulation

Figure 11. Motor Concept with Electrode Configuration

A foreseen issue is the difference in the project location environments and climates. The

HIPEP formulation is developed by DSSP in Reno, Nevada. The desert climate has less water in

the air compared to the Huntsville, Alabama, or Redstone Arsenal (RSA) climate. This may

affect the propellant which is sensitive to temperature and water.

Through this program, the U.S. Army aims to develop an analytical model depicting how

electrically controlled solid propellants perform with regard to tactical sized operation [9 ] . A

timeline of proposed events is listed in Appendix A.

CQL EXPERIENCE

Over the course of the eight-week program, Science Engineering Apprenticeship

Program (SEAP) and College Qualified Leaders (CQL) summer students of Bldg. 7120 toured

the following Redstone Arsenal locations:

Electric Propulsion Laboratory

Propulsion Technology Headquarters

Static Rocket Test Stand and Measurement Center

901 0 Large Rocket Motor Static Test Range

Software Engineering Directorate (SED)

Prototype Integration Facility (PIF)

Russell Tower

Composite Laboratory

Snake Pit and 73 10

In addition, the summer program provided the opportunity for the Electric Propulsion

Laboratory SEAP and CQL students to learn how to:

Conduct electric grounding tests prior to 901 0 rocket motor test

Perform safety checks on fire extinguishers, ladders, eye wash stations, and safety

showers

Fill out purchasing order forms

Operate pallet jacks

Install HD DVR for surveillance cameras in laboratory

Draw schematics in Microsoft Visio

Purchase laboratory materials from RlC Hobby Store

Install motion-sensor light switches

Properly sanitize lab coats

Survey and plan LED lights for 901 0 staircases and surrounding parking lot

Safely operate golf carts

Prepare technical reports following Redstone Scientific Information Center (RSIC)

guidelines

Exchange government vehicle trip tickets at the Motor Pool

Pump gasoline for government vehicles

Contacting companies for obtaining product datasheets

Compile WDI Standard Operating Procedure copies

Measure and cut cables for rocket motor tests

ACKNOWLEDGEMENTS

The author wishes to thank Dr. Patrick Taylor for his dedicated mentorship and guidance

during the summer program at WDI. His expertise on the subject of electrodes and his teaching

abilities create an excellent learning environment for his mentees. In addition, the author

expresses appreciation to Ms. Christina Blankenship and Ms. Alyson Miller for their help during

the research process and their roles as alternative mentors. Appreciation goes to the WDI

Propulsion Technology Lab: Mr. Brendan Babiak, Mr. Mark Fry, Mr. Blain Burgess, Mr. Chuck

Eadon, and Mr. Gary Kirkham. In addition, the author would like to thank SEAP student Mr.

Timothy Little.

Acknowledgement also goes to Ms. Gayla Turner Spivey, Ms. Gabrielle Kelly, and Ms.

Cherlyn Gittens for providing guidance for the SEAP 1 CQL program, preparing summer

students with career development seminars, and other administrative tasks.

Further thanks extend to the University of Alabama in Huntsville (UAH) Honors College

Dean Dr. William Wilkerson, Honors College Advisor Ms. Bethany Wilson, and Honors College

Student Research Coordinator Mr. David Cook.

Additionally, the author tremendously appreciates her parents Mr. Liem Van and Ms.

Carolyn Van for the support provided throughout her life, but especially during her three years of

SEAPICQL. She also expresses thanks to Mr. Winston Van for being supportive brother and

providing plenty of constructive criticism.

LIST OF ABBREVIATIONS, ACRONYMS, AND SYMBOLS

YO Percent

ABIP Air Bag Inflator Propellants

ADN Ammonium Dinitramide

AMRDEC Aviation and Missile Research, Development, and Engineering Center

AP Ammonium Perchlorate

ARDEC Armament Research, Development, and Engineering Center

Bldg Building

BNC Bayonet Neill-Concelman (connector)

BTTN Butanetriol Trinitrate

BuNENA N-Butyl-N-(2-Nitroxyethyl) Nitramine

CL20 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (HNIW)

CQL College Qualified Leaders

Cr Chromium

DEGDN Diethyleneglycol Dinitrate

DoD Department of Defense

DSSP Digital Solid State Propulsion, Inc.

ECEMs Electrically Controlled Energetic Materials

ECESP Electrically Controlled Extinguishable Solid Propellant

ESP Electric Solid Propellant

GAP Glycidol Azide Propellant

HAN Hydroxylammonium Nitrate

HD DVR High Definition Digital Video Recorder

HIPEP High Performance Electrical Propellant

HMX

HTPB

Is,

LLC

Mod

NC

NG

RDECOM

RDX

RSA

RSIC

SEAP

TMETN

UAH

WDI

High Melting Explosive (octahydro-1,3,5,7-tetranitro-1,3,5,7 tetrazocine)

Hydroxyl-Terminated Polybutadiene

Specific Impulse

Limited Liability Company

Modified

Nitrocellulose

Nitroglycerin

Research, Development, and Engineering Command

Royal Demolition Explosive (1,3,5-Trinitro-1,3,5-triazacyclohexane, cyclonite,

hexogen, CAS 12 1-82-4)

Redstone Arsenal

Redstone Scientific Information Center

Science and Engineering Apprenticeship Program

Trimethylolethane Trinitrate

University of Alabama in Huntsville

Weapons Development and Integration Directorate

REFERENCES

1. Sawka, W., & McPherson, M. (2013). Electrical Solid Propellants: A Safe, Micro to

Macro Propulsion Technology. San Jose: American Institute of Aeronautics and

Astronautics.

2. NASA. (201 5, May 5). Specific Impulse. Retrieved from National Aeronautics and Space

Administration: https://www.grc.nasa.gov/www/k- l2/airplane/specimp.html

3. Taylor, Patrick G., "Demonstration of Novel Green Electrical Solid Propellant for Army

Tactical Rocket Propulsion," E-WP4-020, United States (U.S.) Aviation and Missile

Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, AL,

September 201 5.

4. Chung, K., Thompson, D., Rozumov, E., Kaminskyk, D., Fischer, G., & Caflin, K.

"Development of Electrically Responsive Energetic Materials," RDAR-MEE-P, United

States (U.S.) Armament Research, Development and Engineering Center (ARDEC),

Picatinny Arsenal, NJ, December 2014.

5. Electric Field. (n.d.). Retrieved from Hyper Physics: http:/hyperphysics.phy-

astr.gsu.edu/hbase/electric/elefie.html

6. Peng,H.Y.;Pu,L.;Wu,J.C.;Cha,D.;Hong,J.H.;Lin,W.N.;Li,Y.Y.;Ding,J.F.;

David, A.; Li, K., & Wu, T., "Effects of electrode material and configuration on the

characteristics of planar resistive switching devices." APL Mater, 1, 0521 06 (2013), DOI:

http://dx.doi.org/l 0.106311.4827597

7. IEEE. (n.d.). Electrodes and Electrode Materials Information. Retrieved from

Engineering 360:

www.globalspec.com/learnmore/materials~chem icals~adhesives/electrical~optical~specia

Ity-materials/electrical-contact - electrode - materials/electrical~contact~electrode~materia

Is

8. "Thoriated Tungsten Radioactivity." Pro-Fusion. http://pro-

fusiononline.com/tungsten/radioactivity.htm (accessed June 20, 20 16).

9. Taylor, Patrick G., "Demonstration of Novel Green Electrical Solid Propellant for Army

Tactical Rocket Propulsion," Powerpoint. E-WP4-020, United States (U.S.) Aviation and

Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal,

AL, September 20 15.

APPENDIX A

Research Plan for Electromagnetic and Mechanical Modeling of Ignition and Combustion

Phenomena of Electrically Controlled Solid Propellants

Year 1 Basic Electrode Modeling o Field pattern behavior o Current density and ion mobility behavior o Baseline modeling of standardized electrode geometries o Iterations of basic model with different materials and geometries Subscale Propellant Analysis o Burn Rate Analysis of ESP candidate test propellant(s) o Simple combustion analysis of ESP candidate test propellant(s) o EM radiated field ignition threshold testing

Year 2 - Basic Electro-Ballistic Modeling o Integration of Propellant Behavior Model o Prediction Modeling of Ballistic Behavior o Prediction Modeling of Thermal Behavior o Examine Scaling Effects Subscale Motor Analysis o 2x4 Motor Configurations o Burn Rate, Combustion, DetonationIDeflagration, Packaging Analysis

Year 3 Advanced Electro-Ballistic Modeling o Motor testing Validation o Mass Regression Behavior modeling Tactical Simulant Motor Analysis o Prototype Tactical Test Unit Design o Scaled up Motor Characteristic Performance

Project Timeline

Basic Electrode Model

Development propellant

Fundamental Behavior Analysis

Basic Electrode Design & Analysis

Electro-Ballistic Model

Development Subscale Motor Analysis (feeds Model Update) ,

I

- . .

Advanced Electro-Ballistic I

Model Development

I . - - -. . -. . . . -.

Propellant Scale Up Behavior Analysis . . . .

~acti-cal Motor Simulator . .

Model Verification &

Reporting . - .- -

APPENDIX B

Electrode Materials

Electrode Materials

Other

Good for recording electrodes

Copper strengthened (& other alloys) but then not as conductive; high signal to noise ratio; low contact impedance; stability

Used in phantoms

Used a lot in gas tungsten arc welding (GTAW); flatter tips had less pressure, slower arc velocities, and resultant plasma temp. more uniformly distributed

Hexagonal crystalline structure

Forms alloys tungsten, ruthenium, iridium; high contact resistance films in organic vapors

Gold

Silver I AgCl

Copper Stainless Steel

Tungsten

Graphite & Carbon

Platinum

Price

Expensive

More expensive than graphite

Fine graphite costs more; graphite common EDM electrode (cheap)

Expensive

Strennth

Very soft

Stronger than silver

Soft, lubricant

High

Conductivity

Most conductive

2nd to silver

Titanium

Oxidation1 Corrision

High oxidation resistance

Oxidizes easily

Carbon- very high sublimation temperature so resistant to high-temperature arcs, corrosion resistant; Fine graphite grains high wear resistance ($$$)

Resists erosion & corrosion

strength1 weight Corrision resistance

Brass (copper & zinc alloy)

Palladium

Mixed metal oxide (MMO)

Less conductive than copper

ratio

Less wear resistant compared to tungsten and copper

Resists erosion & corrosion

Small tubular electrodes

Forms alloy with ruthenium and copper; high contact resistance films in organic vapors

Oxide coat over inert metal or carbon core

Easy to machine

Expensive Titanium oxides (most common) lower cost

APPENDIX C

Electrode Catalogue Options

- -

Electrode Electrode Material

Cole-Parmer Combination Ion Selective SilverlSulfide Electrodes, SilverlSulfide(Ag+/S2)

,.-

BIOANALYTICAL SYSTEMS INC LC $487.03 Each For Thin-Layer Flowcell;

DUAL AU WRK ELECT-CF-3MM mm Dual 3mm Gold electrode

BIOANALYTICAL SYSTEMS INC EC Electrode, RDE-2

$270.71 Each 3 mm Rotating Disk; Gold RDE GOLD ELECTRODEIRDE-1-3MM

BIOANALYTICAL SYSTEMS INC LC For Thin-Layer Flowcell;

3UAL GCE AND GLD WRK-CF3MM $487.03 Each 3 mm Dual 3mm Glassy

carbonlgold electrode

Thermo Scientific DISPOSABLE $540.65 1 Pack of 6 Gold on PTFE Disposable

ELECTRODE GOLD 6PK Electrode (6 pack)

--

BIOANALYTICAL SYSTEMS INC LC -,:I $3&r $487.03 Each For Thin-Layer Flowcell; DUAL AU WRK ELECT-CF-3MM

Thermo ScientificTM OrionTM SilverlSulfide Electrodes

YSITM Truline Lab Selective Ion Electrode, SilverlSulfide (Ag+lS2-)

I Jl , I 1 1 1 1 - I --

.. ,

-- - - - 1

Silver 1 'I

?h-. -.r I

:Silver;+ A: - 1

.I

$749.77 - $922.51 Each

$1,004.74 Each

Dual 3mm Gold electrode

0" to 80°C

Uses four sensor technology; Solid state; Double Junction

I Copper

I 1 Platinum or stainless

1 steel, outer- stainless steel

Stainless Steel

Epoxy electrodes with solid-state 80 C, BNC Connector, membranes--Copper (Cu+2) Double-junction

FHC INC CONCENTRIC BIPOLAR $645.1 5 1 Pack of 3 For research, not human

ELECTRODE Custom use

?LASTICS ONE INC CUSTOM $31.01 Each Win order 4 (contact for

CONCENTRIC ELECTRODES current pricing)

MICRO PROBE INC CONCENTRIC ELECTRODE, PLATINUM -$467.74 Each

Miller Electric Tungsten Electrode, 3/32 I Hazardous material; May

In Dl 7 In Ll PKIO (Grainger) $57.90 / Pack of 10 3132x7 in. cause cancer but does NOT contain Thorium

Fisher ScientificTM accumetTM Glass Body Ag/AgCI Reference Electrodes - $1 65.24 - $281.84

Each 0" to + I 10'C Mercury-Free

; car 1 , Tungsten

HONORS COLLEGE THE UNIVERSITY OF ALABAMA IN HUNTSVILLE

Honors College Frank Franz Hall

+ l (256) 824-6450 (vo~ce) + I (256) 824-7339 (fax)

Honors Thesis Copyright Permission

This form must be signed by the student and submitted as a bound part of the thesis.

In presenting this thesis in partial fulfillment of the requirements for Honors Diploma or Certificate from The University of Alabama in Huntsville, I agree that the Library of this University shall make it freely available for inspection. I further agree that permission for extensive copying for scholarly purposes may be granted by my advisor or, in hislher absence, by the Chair of the Department, Director of the Program, or the Dean of the Honors College. It is also understood that due recognition shall be given to me and to The University of Alabama in Huntsville in any scholarly use which may be made of any material in this thesis.

vnq Student Name (printed)

V&& 76 Student Signature

8/is/l b Date