The Asia‐Pacific Conference on Combus on (ASPACC) is an important biennial event in the
calendar of the Combus on Ins tute. Now in its 11th conference, the ASPACC was ini ated in
1996 with the aim of promo ng and advancing combus on science and technology in the Asia‐
Pacific region. A key objec ve of ASPACC is to promote global and regional scien fic partnerships
that will accelerate the advent of clean, efficient and versa le combus on technologies. The first
ASPACC conference was held in Osaka, Japan in 1997, followed by Tainan, Taiwan (1999), Seoul,
Korea (2001), Nanjing, China (2003), Adelaide, Australia (2005), Nagoya, Japan (2007), Taipei,
Taiwan (2009), Hyderabad, India (2010), Gyeongju, Korea (2013), and Beijing, China (2015).
The 11th ASPACC will be hosted by the Australia and New Zealand Sec on of the Combus on Ins tute (ANZCI) and is scheduled for December 10‐14, 2017. It will be held at the University of Sydney in conjunc on with the 2017 Australian Combus on Symposium and the Eighth Australian Conference on Laser Diagnos cs in Fluid Mechanics and Combus on. The technical program is already enriched with seven leading Keynote Speakers promising exci ng presenta ons in broad areas of combus on (see next page). Please access conference website:
h p://www.anz‐combus onins tute.org/ASPACC2017/index.php
The University of Sydney, is Australia’s oldest and one of its leading research‐intensive universi es. Sydney is a beau ful des na on that promises to provide visitors with beau ful landscape, famous beaches and amazing entertainment. Serene mountains and wine country are only within a 3‐hour drive. Sydney is easily accessible to delegates around the world, with more than 40 interna onal airlines offering over 670 flight arrivals each week.
11TH ASIA PACIFIC CONFERENCE ON COMBUSTION (ASPACC-11),
10-14 DECEMBER, 2017 THE UNIVERSITY OF SYDNEY, AUSTRALIA
Submission of full paper (4 pages): 7th July 2017
No fica on of paper acceptance: 28th August 2017
Submission of revised paper: 11th September 2017
Conference dates: 10th‐14th December 2017
Important Dates:
8:30
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-2080Laminar Flames
Dr Scott Steinmetz
Turbulent Flames
Professor Yongmo Kim
IC-EnginesDr Nic Surawski
Biomass, Coal & MILD
CombustionDr Michael
Evans
Soot, PAH & Material Synthesis
Professor Akira Yoshida
New Burners & Concepts
Professor Kumar Sudarshan
Gas TurbinesDr Sandeep Jella
Spray, Droplets & Supercritical
Dr Agisilaos Kourmatzis
DiagnosticsDr Callum Atkinson
9:30 P319: Outwardly Propagating Spherical Flame with Cellular Instability and Laminar Burning Velocities in Methane/ethylene/air Premixed FlamesK. H. Van,H. J. Kim,J. Park,Oh Boog Kwon,Dae Keun Lee,Seung Gon Kim,Young Tea Guahk,Dong-Soon Noh,S. H. Chung
P405: On the Joint Statistics of Mixture Fraction and Reaction Progress Variable in Mixed Modes of CombustionH.C. Cutcher,A.R. Masri,R.S. Barlow,G. Magnotti
P338: Preliminary comparison of chemical heat storage systems for saving exhaust gas energy in gasoline and diesel enginesDuc Luong Cao,Guang Hong,Tuan Le Anh
P151: Mercury removal from coal-fired flue gas by modified clay mineralsHuan Liu,Lin Chang,Yongchun Zhao,Junying Zhang,Jihua Qiu
P313: Characteristics of oxygen-enriched laminar ethylene diffusion sooting flamesZhiwei Sun,Bassam Dally,Zeyad Alwahabi,Graham Nathan
P170: A Study on the Basic Combustion Characteristics in a Metal Fiber BurnerJaehyeon Kim,Minsoek Han,Keunseon Sim,Keeman Lee
P419: Burn Rate Characterization of an Alternative Monopropellant –Hydroxyl Ethyl Hydrazinium NitrateUmakant Swami,K. Jayaraman,Arindrajit Chowdhury
P510: Investigations on Ignition of Atomized Fuel-Air Mixtures and Liquid Fuel Column-air Combinations by Low Energy Laser PulsesAwanish Pratap Singh,Upasana P. Padhi,Harikrishna Tummalapalli,Ratan Joarder
P106: Emission Spectroscopy of the C2 Swan Bands to Estimate Temperature of the Near-Extinction Flamelets of Turbulent Premixed FlamesYuzo Kawasoe,Hideki Hashimoto,Osamu Moriue,Eiichi Murase,Junichi Furukawa
Thursday, 14 December 2017Plenary Lecture: Advanced Optical Diagnostics at Engine Conditions, Dr Lyle M. Pickett
Chair: Professor Shawn KookAuditorium B2010
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-20809:50 P334: Effects of
Additional Diluents on Laminar Burning Velocities and Cellular instabilities in Outwardly Propagating Methane/Ethylene-Air Premixed Spherical FlameH. J. Kim,K. H. Van,J. Park,O. B. Kwon,Dae Keun Lee,Seung Gon Kim,Young Tae Ghauk,Dong soon Noh
P009: Study On the Statistical Analysis Methodology of the Swirl Flame DynamicsZheng Yu,Zhang Chi,Huang Min
P347: Effect of injection strategies on preignition tendency in a turbocharged single cylinder engine.Eshan Singh,Adrian Ichim,Kai Morganti,Robert W. Dibble
P157: A burning Pyrotechnic Film with Millimeter-wave RadiatingZhu Chen-guang,Peng Ru,Xu Jing-ran,Xie Xiao
P331: Soot Precursor Evolution in Diffusion Flames with Different Sooting PropensitiesDaniel Bartos,Matthew Dunn,Mariano Sirignano,Andrea D’Anna,Assaad R. Masri
P169: An experimental investigation of the heat transfer performance in a hybrid solar receiver combustor operating with the solar-only and combustion-only modesAlfonso Chinnici,Zhao F. Tian,Graham J. Nathan,Bassam B. Dally
P428: Ignition Delays of Blended Unsymmetrical Dimethyl Hydrazine with an Energetic Ionic Liquid Umakant Swami,Mahesh Dalwani,Krishna Mohan,Arindrajit Chowdhury
P016: Experimental and Numerical Investigation of Spray Characteristics of Butanol-Diesel blendsSattar Jabbar Murad Algayyim,Andrew P. Wandel,Talal Yusaf
P126: Measurement on evaporation characteristics of multi-component fuel sprayWenyuan Qi,Yuyin Zhang,Shunhua Yang
10:10 P348: Propagation behaviors of twin premixed methane flame in a counterflow annular slot-burner under DC electric fieldsSung Hwan Yoon,Min Suk Cha
P253: Effects of Karlovitz number on Localised Forced Ignition of Stratified Combustible Mixtures: A Numerical InvestigationDipal Patel,Jiawei Lai
P358: Effect of CO2 Dilution on End-gas Auto-ignition in a Rapid Compression MachineYunliang Qi,Yingdi Wang,Yanfei Li,Hui Liu,Zhi Wang
P466: Cold Plasma Methane ReformingAmit Kumar,Anand M. S,L Rao,Dasappa S
P340: Effects of Adiabatic Temperature and Chemical Composition on Soot Formation in Laminar Diffusion FlamesAwais Ashraf,Daniel Bartos,Matthew J. Dunn,Assaad R. Masri
P284: The Role of Co-injected Hydrocarbon Gas with Oxygen in a FurnaceLe-Kuan Lin,Cheng-Hao Hou,Sheng-Yen Hsu,Jyun-Sheng Wang,Yung-Chang Liu,Chien-Hsiung Tsai
P463: PIV Investigation on Effects of Circular DBD Plasma Actuator on Turbulent Swirling Premixed FlameSujoy Chakraborty,Masayasu Shimura,Mamoru Tanahashi
P307: Droplet combustion studies on an RP-1 surrogate and its constituent fuelsAnand Sankaranarayanan,Arindrajit Chowdhury,Neeraj Kumbhakarna
P127: An optical absorption method to deduce the temperature dependence of gas viscosity Rongkang Gao,Sean O’Byrne
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-208010:30 P351: Effect of
fuel variation, plate material, and thickness on dynamics of precursors to blow out of shear layer stabilized premixed flame Arun K Ampi,T M Muruganandam
P481: Comparison of chemical mechanisms for n-dodecane at engine conditions using an unsteady flamelet modelArmin Wehrfritz,Bruno Savard,Evatt R. Hawkes
P370: Simulation of Knock and Super-Knock in SI EnginesM. Jaasim,F. E. Hernández Pérez,S. Vedharaj,V. Raman,R. W. Dibble,Hong G. Im
P312: Thermogravimetric Analysis of Sludge Pyrolysis Oil Mixed with Heavy Fuel OilSamuel Chatelier,Yong Hao Kuan,Guan-Bang Chen,Hsien-Tsung Lin,Ta-Hui Lin
P357: An investigation of high power laser pulses on soot using an IR pump UV probe approachHamdy A. Ahmed,Matthew J. Dunn,Daniel Bartos,Assaad R. Masri
P129: Experimental study on the effects of equivalence ratio & reactor length on flame characteristics in micro scale reactorsMaryam Yeganeh,Sadegh Tabejamaat,Amin Aramesh,Mohammadreza Baigmohammadi
P464: How transverse acoustic velocity affects flame response to axial acoustic perturbationsAditya Saurabh,Christian Oliver Paschereit
P094: Time-resolved investigation of droplet size and velocity inside diesel fuel spraysZehao Feng,Mingzhi Zhang,Jiapei Yang,Chenglong Tang,Zuohua Huang
P139: Characteristics of an acoustically forced non-premixed jet flameK.K. Foo,Z.W. Sun,P.R. Medwell,Z.T. Alwahabi,G.J. Nathan,B.B. Dally
10:50 Break
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-2080Laminar FlamesProfessor Hong
Im
Turbulent Flames
Dr Thibault Guiberti
IC-EnginesDr Timothy
Bodisco
Biomass, Coal & MILD
CombustionProfessor
Zongjie Hu
Soot, PAH & Material Synthesis
Dr Matthew Dunn
New Burners & Concepts
Dr Paul Medwell
Gas TurbinesDr Robert Gordon
Catalysis & Surface
ChemistryProfessor
Shuiqing Li
DiagnosticsDr Zhiwei Sun
11:20 P369: Flame Modes and Combustion Characteristics of a Triple Port BurnerChun-Han Chen,Chao-Wei Huang,Yueh-Heng Li
P502: Temperature imaging of gaseous n-heptane flames in hot vitiated coflowsM.J. Evans,P.R. Medwell,Z.W. Sun,B.B. Dally
P434: A Study of Natural Gas Mixing Percentage on Combustion and Emission Characteristics of a CNG-Diesel Dual-Fuel EngineOcktaeck Lim,Shubhra Kanti Das,Kyeonghun Jwa
P231: Reaction Zone Structure of Syngas Combustion under MILD and Conventional ConditionsSantanu Pramanik,R. V. Ravikrishna
P359: Experimental and kinetic modeling investigation on premixed tetralin flamesYuyang Li,Wenhao Yuan,Chuangchuang Cao,Yan Zhang,Jiabiao Zou,Yizun Wang
P341: A Five-Equation Model for the Simulation of Miscible, Compressible Fluids Including Molecular Species TransportMichael Groom,David Youngs,Ben Thornber
P465: Noise-induced dynamics in a stable thermoacoustic system: Numerical evidence of coherence resonanceVikrant Gupta,Aditya Saurabh,Christian Oliver Paschereit,Lipika Kabiraj
P396: Investigation of Wall Chemical Effect on Weak Flame with GC and PLIFSui Wan,Yong Fan,Kaoru Maruta,Yuji Suzuki
P214: Mapping of instantaneous fuel concentration using a bundled LIBS plugHyung Min Jun,Hyunwoo Kim,Jai-ick Yoh
11:40 P373: Mode-Switching Behaviour of Preheated and Diluted Flames in a Stagnation BurnerBin Jiang,Robert. L. Gordon,Mohsen. Talei
P506: Multi-Environment Probability Density Function Approach for Turbulent Partially-Premixed Methane/Air FlamesNamsu Kim,Yongmo Kim
P449: Combustion of Methanol in Diesel Engine Using Diethyl Ether as Ignition EnhancerR. Vallinayagam,S. Vedharaj,Mohammed Jaasim,Hong G. Im,S.M. Sarathy,R.W. Dibble
P252: Large Eddy Simulation of MILD Combustion of SyngasSantanu Pramanik,R. V. Ravikrishna
P460: Formation of Incipient Soot Particles from Polycyclic Aromatic Hydrocarbons: A ReaxFF Molecular Dynamics StudyQian Mao,Adri C.T. van Duin,K. H. Luo
P509: Tomographic background-oriented schlieren techniques for three-dimensional density field reconstruction in shock-containing flowsR. Kirby,D. J. Tan,C. Atkinson,D. Edgington-Mitchell
P500: Large Eddy Simulation of a Dual Swirl Gas Turbine Model Combustor with Self-excited Thermo-acoustic InstabilityZhi X. Chen,N. Swaminathan
P206: Catalytic Effect of Graphene Oxide on the Oxidation of Paraffin-based FuelsLin-lin Liu,Can-yu Zhang,Yin Wang,Song-qi Hu
P324: A Tomographic Background-Oriented Schieren Method for 3D Density Field Measurements in Heated JetsC. Atkinson,S. Amjad,J. Soria
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-208012:00 P115: Flame
Instability of Synthetic Liquefied Petroleum Gas and Natural Gas on Ceramic Porous BurnerAmornrat Kaewpradap,Sumrerng Jugjai
P280: An Experimental Study on Flame Behavior with Porosity of Center Plate in a Low-Swirl CombustorMinsoek Han,Chul-Ho,Kim,Keeman Lee
P452: Characteristics of Gasoline/Methane Dual_Fuel Combustion in a Spark-Ignited EnginesNan Li,Haiqiao Wei,Jiaying Pan,Jianxiong Hua,Gequn Shu
P288: On MILD Combustion in a Perfectly Stirred Reactor with Exhaust Gas RecirculationYang Zhang,Yuxin Wu,Hai Zhang,Qing Liu,Junfu Lv,Guangxi Yue
P471: Laser-Induced Incandescence in Turbulent Non-Premixed Flames at Elevated PressureWesley Boyette,Emre Cenker,Thibault Guiberti,William Roberts
P204: Effect of Miller Cycle and Fuel Injection Strategy on Performance of Marine Diesel Engine Xiuxiu Sun,Xingyu Liang,Peilin Zhou,Yuehua Qian,Teng liu,Bo Liu
P505: Numerical studies on characteristics of perforated and slotted plates under thermoacoustic instability conditionSeungtaek Oh,Kiyoung Jung,Youngjun Shin,Yongmo Kim
P503: Characteristics of Hydrogen produced by Methanol Reformation in Compact Whirling Orbital Plate Fluidized Bed Reactor Prashant Nehe,Sudarshan Kumar,V. Mahendra Reddy
P366: Flame temperature measurement using color-ratio pyrometry with a consumer grade DSLR cameraAnand Sankaranarayanan,Umakant Swami,Arindrajit Chowdhury,Neeraj Kumbhakarna
12:20 P468: Influence of gas expansion on the interaction between spatially periodic shear flow and premixed flameRuixue Feng,Hongtao Zhong,Damir Valiev
P183: Numerical Simulation of LPG-Hydrogen Jet Diffusion flamesMuthu Kumaran S,Vamsi Krishna Ch.,Vasudevan Raghavan
P461: A Computational Study of Pre-ignition to Detonation Transition in a One-Dimensional ChamberAliou Sow,Mohammed Jaasim,Francisco E. Hernández Pérez,Hong G. Im
P496: Combustion characteristics of a methane jet flame in hot coflow of O2/H2O vs. O2/N2Z. Shu,C. Dai,K. Cheong,J. Mi
P499: The investigation of the performance of the after-treatment devices on the diesel and biodiesel particlesYi Guo,Svetlana Stevanovic,Mohammad Jafari,Puneet Verma,Richard Brown,Chiemeriwo Godday Osuagwu,Barbara D’Anna,Zoran Ristovski
P339: Kinetic Modeling of Engine Combustion: an Uncertainty AnalysisSong Cheng,Yi Yang,Michael J. Brear
P513: Turbulence Model Effects on Multiple-Swirl Flame AerodynamicsSandeep Jella,Wing Yin Kwong,Jeffrey Bergthorson,Gilles Bourque,Adam Steinberg
P163: Development of SCR System with Optimized DEF Dosing Strategy to Meet BS-VI Emission NormsDhanyakumar K,Prachetas K,Swapnil S,Amit P,Brijesh P
P276: Propane Spray Structure in an Optically Accessible Direct Injection, Spark Ignition Engine: A Post-Processing Algorithm for Planar Laser Mie-ScatteringH.B. Aditiya,J.S. Lacey,M.J. Brear,R.L. Gordon,C. Lakey,S. Ryan,B. Butcher
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-208012:40 P469: The Effect
of Carbon Dioxide Diluted on Combustion Characteristic with a Tubular Flame BurnerJie Hu,Baolu Shi,Kazuhiro Hayashida,Dasukei Shimokuri
P279: Hybrid RANS/PDF simulations of the Adelaide jet-in-hot-coflow burner using 3D FGM tabulated chemistryAshoke De,Gerasimos Sarras,Dirk Roekaerts
P474: LES on Knocking Combustion and End-gas Auto-ignition Based on A Downsized Spark-ignited EngineJiaying Pan,Haiqiao Wei,Gequn Shu
P498: Preliminary investigation by experiment on the premixed MILD combustion of C3H8 in a cylindrical furnaceKin-Pang Cheong,Guochang Wang,Bo Wang,Jianchun Mi
P512: Application of spatially resolved emission spectroscopy to study low-pressure premixed ethylene/air sooting flames S. Algoraini,S. Zhiwei,Z.T. Alwahabi
P197: Complete catalytic oxidation of propene over thin film catalystAchraf El Kasmi,Guan-Fu Pan,Zhen-Yu Tian
P246: Determination of Pressure Waveform in a T-burner Based on Standing Wave RatioAnchen Song,Junwei Li,Bingbing Sun,Xinjian Chen,Ningfei Wang
P271: Surface mechanism for the ammonia oxidation over Pt(111)Juan D. Gonzalez,B. S Haynes,Alejandro Montoya
P277: OH Imaging in a Non-Uniform, Hydrogen-Fueled Scramjet EngineTristan Vanyai,Stefan Brieschenk,Timothy J. McIntyre
13:00
14:15
Lunch
Plenary Lecture: The Challenges and Prospects of Spark Ignition Engines and Fuels, Professor Michael J. BrearChair: Professor Evatt Hawkes
Auditorium B2010
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-2080Laminar FlamesProfessor Hong
Im
Turbulent Flames
Dr Thibault Guiberti
IC-EnginesDr Timothy
Bodisco
Biomass, Coal & MILD
CombustionProfessor
Zongjie Hu
Soot, PAH & Material Synthesis
Dr Matthew Dunn
New Burners & Concepts
Dr Paul Medwell
Gas TurbinesDr Robert Gordon
Catalysis & Surface
ChemistryProfessor
Shuiqing Li
DiagnosticsDr Zhiwei Sun
15:15 P476: Measurements of Laminar Burning Velocity of Gasoline Surrogate Fuel/Air/EGR Gas MixturesShota Doi,Hirokazu Uesaka,Ryosuke Matsui,Masamichi Matsuura,Ryunosuke Okazaki,Hidefumi Kataoka,Daisuke Segawa
P281: Investigation of NOx in pilot stabilized flames using Eddy Dissipation Concept modelRohit Saini,Ashoke De
P477: The principle of determining the optimized operating parameters based on the adopted fuel property in RCCI enginesYaopeng Li,Ming Jia,Yachao Chang,Maozhao Xie
P142: Cu and Cu2O oxidation in chemical looping processes: a first-principles theory studyJie Cao,Haibo Zhao,Yongliang Zhang
P361: Prediction of sooting tendency of gasoline surrogate fuelsMuhammad Kashif,Guillaume Legros,Jérôme Bonnety
P316: Assessment of 3D printing technology for potential application towards manufacturing composite propellantsAnirudha Ambekar,Jai-ick Yoh
P128: Linear instability and DC shift in tactical missile solid rocket motors – a computational studyVishal Wadhai,Varunkumar S
P350: Properties of in-cylinder fuel reformation and ignition characteristics of CO/H2/CH4 mixturesYuki Murakami,Hisashi Nakamura,Takuya Tezuka,Susumu Hasegawa,Go Asai,Kaoru Maruta
P297: Schlieren CT Measurement of 3D Density Distributions of Flame Kernels of Spark-Ignited Direct-Injection of Free, Cavity-Guided and Plane-Guided Fuel Jets Ahmad Zaid Nazari,Yojiro Ishino,Takanori Motohiro,Ryoya Yamada Yuta Ishiko,Yu Saiki
Room LT-1040 CS-1050 LT-1130 CS-1060 CS-1170 CS-2140 CS-2150 CS-2090 CS-208015:35 P487: Laminar
lifted flames in diesel engine conditionsD.K. Dalakoti,A. Wehrfritz,B. Savard,H. Wang,E.R. Hawkes
P095: RANS/MMC modeling of piloted turbulent dimethyl ether/air jet diffusion flameSanjeev Kumar Ghai,Santanu De,Ashoke De
P343: Influence of bio-syngas hydrogen fraction on spark ignited engine in-cylinder heat transfer and combustion dynamicsAnand M Shivapuji,S Dasappa
P074: Autoignition behavior of Fuel Rich Natural Gas/ Air Combustion Product Jet Discharged into Quiescent AirSaeedreza Zadsirjan,Sadegh Tabejamaat,Masoud E. Attarzadeh
P212: Characteristics of Pure Oxygen/methane Flames in a Rapidly Mixed Tubular Flame Burner Baolu Shi,Bo Li,Guoxing Wang,Xiaoyao Zhao,Jie Hu,Ningfei Wang
P352: Stabilization and Emission Characteristics of Ammonia Flames in a Micro Gas Turbine CombustorEkenechukwu C. Okafor,Kazuma Sakai,Akihiro Hayakawa,Taku Kudo,Osamu Kurata,Norihiko Iki,Hideaki Kobayashi
P192: Metallic mesh and quartz wafer as emitter-filter for a thermophotovoltaic systemJ.R. Llobet,X. Kang,and A. Veeraragavan
P401: Phase resolved PLIF measurements in puffing plumesKuchimanchi K Bharadwaj,Debopam Das,Pavan K Sharma
15:55
16:00
End of Day
Farewell Reception: Abercombie Building
11th Asia-Pacific Conference on Combustion,
The University of Sydney, NSW Australia
10th -14th December 2017.
Assessment of 3D printing technology for potential application towards manufacturing
composite propellants
Anirudha Ambekar1 and Jai-ick Yoh1
1Department of Mechanical and Aerospace Engineering, Seoul National University
Seoul, 151-742, Korea
Abstract
Ammonium perchlorate based solid composite propellants are
conventionally manufactured by a casting process. The casting
of propellants is highly resource intensive and demands a shaped
mold for each grain shape to be casted. This limits the number
of grain shapes that can be tested with various propellant
compositions. As the grain shape directly affects the
performance of a propellant charge, innovative grain geometries
could provide significant boost in performance. 3D printing
techniques are a subset of additive manufacturing or rapid
prototyping and provide the capability of quick and economical
manufacture. Thus, application of these techniques for
composite propellant manufacture has the potential to allow the
study of parametric variation of propellant shapes with ease. This
article presents an exploratory study aimed at application of 3D
printing techniques for manufacturing composite propellants.
1 Introduction
Solid composite propellants are prominent amongst the range of
available energetic materials due to their high energy density,
simplicity, and relative safety. The conventional method of solid
rocket motor manufacturing involves casting of a slurry
containing oxidizer, fuel, binder, and curing agents into a mold.
This technique relies on molds and shaped patterns to create the
grain shape, which subsequently determines the thrust profile for
a given rocket. Furthermore, longitudinally varying grain
geometry has been proposed [1 , 2 , 3 for improved grain
performance. However, the process of creating these molds and
patterns is costly and time consuming. Thus, production and
testing novel grain patterns is considerably resource intensive.
This is a significant limitation in parametric design, optimization,
and testing of solid rocket propellants.
In contrast to conventional casting, additive manufacturing (AM)
or 3D printing is inherently capable of a rapid design and
manufacturing cycle irrespective of the geometric complexity of
objects to be manufactured. In typical 3D printing process, three-
dimensional objects are created by successive deposition of
layers of a given material, which is typically a thermoplastic or
a UV hardening resin. Fused deposition modeling (FDM) and
selective laser sintering (SLS) are two AM techniques, which
have found widespread usage in many fields. The application of
AM technology to solid rocket propellants would provide greater
freedom for testing multiple grain patterns, novel compositions,
and optimization of solid rocket motors.
Previously, the FDM technology has been used for fabrication of
hybrid rocket grain by Fuller et al. [4 , Whitmore et al. [5, 6 ,
and Derrick et al. [7 . While, sugar-KNO3 based composite
propellants were manufactured using the SLS technique by
Brown et al. [8 . Furthermore, Cattani et al. [9 have recently
reported a preliminary study regarding printing energetic
composite filaments to be used for 3D printing.
1.1 Basics of 3D printing
The term 3D printing is most commonly used to refer to fused
deposition modelling. In this technique, a thermoplastic polymer
such as acrylonitrile butadiene styrene (ABS) and polylactic acid
(PLA) in the form of a filament is heated to its melting point and
pushed through a heated nozzle. The movement of the nozzle is
controlled through a computer and molten material exiting the
nozzle is laid on a plate to create desired shape. The
thermoplastic laid on the plate cools rapidly, below the glass
transition temperature of the polymer, and acquires a solid form.
The repeated extrusion and controlled nozzle movement is used
to build successive layers of plastic to create desired object. The
key requirement for the correct function of a FDM based 3D
printer lies in keeping the thermoplastic “liquid in the nozzle and
solid on the build plate”.
1.2 Objective
The objective of the current study may be stated as assessing
simple 3D printing technology for manufacturing ammonium
perchlorate composite propellants (APCP). The techniques
envisaged here seek to replace the conventional casting method
and may provide several advantages such as relatively quick
design and fabrication of any grain shape, rapid testing with
novel compositions, reduced cost due to due reduced tooling,
scalability, and accuracy of geometrical patterns, and possibility
of creating functionally graded propellants. The 3D printing
techniques can potentially also create grains with longitudinally
varying geometry.
In addition to being the most common material used for 3D
printing, ABS has been considered as a fuel for hybrid [10 as
well as composite propellants [11 . Current study conducts a
theoretical assessment of the performance of an ABS based
propellant with conventional APCP and proposes a fabrication
technique for such a propellant.
2 Potential techniques of 3D printing APCP
The origin of this study was merely based on the notion that 3D
printers may be used for composite propellant manufacture. The
study in this initial stage has been largely exploratory with
significant literature review and various trials to ascertain
viability of future scope.
Corresponding author. Fax: +82-2-882-1507
E-mail address: [email protected]
A commercial FDM printer (Ecubmaker fantasy II) shown in Fig.
1 was utilized for this study in conjunction with slicing software
Cura 15.04 and 3D modelling software freeCAD version 0.16.
Figure 1: Ecubmaker fantasy II FDM 3D printer with assortment
of components.
The potential techniques, which may be used to manufacture
APCP with a modified 3D printer, include direct printing with
AP-HTPB slurry, 3D printing of molds, dual extrusion technique,
and solvent extrusion technique. Following paragraphs discuss
each of these methods in detail.
2.1 Direct printing with AP-HTPB slurry
Typical composite propellants consist of the oxidizer ammonium
perchlorate (AP), aluminium particles as fuel, the binder
hydroxyl-terminated polybutadiene (HTPB), and certain curing
agents. The ingredients are typically mixed in batch process and
the resulting slurry is cast into moulds for curing. The initial
viscosity of the slurry [ 12 is similar to that of molten
thermoplastic [13 .
An attempt was made to use the 3D printing technology for
directly printing the grain shape with the propellant slurry. The
3D printer was modified to interface with a paste extruder. The
paste extruder was fabricated in-house using ABS thermoplastic
and the 3D printer. Figure 2 shows different views of the paste
extruder assembly spate and mounted on the 3D printer. The
original design of the paste extruder was tweaked to accept
standard 5 ml syringes which would hold the propellant slurry.
Figure 2: Paste extruder for APCP slurry printing.
However, as the curing time for HTPB bonded propellants is
significantly longer [14 , the printed shape of the grain was not
maintained. Figure 3 shows an attempt of printing the wagon
wheel grain with AP-HTPB propellants mixed in 75:25 ratio.
However, the shape of the profile could not be maintained due to
low viscosity of the propellant composition at this stage of
curing.
Figure 3: A trial print of wagon-wheel grain geometry with 75:25
AP-HTPB slurry showing issues due to low viscosity and high
curing time.
Therefore, due to the long curing times AP-HTPB based
composite propellants cannot satisfy the “liquid in the nozzle and
solid on the build plate” requirements and use of molds was
deemed necessary.
2.2 3D printing of molds
This method provides a simple approach wherein the mold of the
desired shape is pre-printed using a standard 3D printing
technique. The 3D printing process of the mold provides the
opportunity of rapid manufacture of intricate core shapes
without the need of complex tooling. The typical 3D printing
materials such as ABS and PLA may be utilized for this purpose.
Figure 4 shows the 2D and 3D model as well as samples
fabricated from ABS plastic for a simple star grain designated
‘A’ and a helical star grain ‘B’.
Figure 4: 2D cross-section of a star grain, 3D model a helical star
grain, and samples fabricated from ABS plastic.
The fabrication of complex helical geometry was rendered easily
with the 3D printing method. Thus, establishing the utility of this
method for creating complex grain geometry. With appropriate
design process determining the various dimensions of the mold,
sufficient mechanical strength can be ensured.
The central core, forming the internal geometry of the propellant
grain, may be designed to be removable through techniques such
as melting and solvent dissolution or it could be designed to be
burnt in place with the AP-HTPB propellant. The outer layer of
the mold may be integrated into or function as a part of the motor
casing similar to recently 3D printed rocket motor [15 .
The technique of 3D printed molds was implemented with two
simplified geometries viz. wagon wheel and plane cylinder. The
outer diameter of the wagon wheel grain was 30 mm with
minimum web thickness of approximately 4 mm and a thickness
of 5 mm. the end burning plane cylindrical grain had an outer
diameter of approximately 18 mm and height of 8 mm. A hand-
mixed composition with AP-HTPB-IPDI in the proportion of
77%:20.5%:2.5% was manually filled in these molds. The filled
molds were cured at 60 ° for 8 days and the cured propellant was
separated from the mold by cutting. The resulting sample grains
have been shown in Fig. 5.
(a) (b)
Figure 5: (a) Cylindrical grain (b) wagon wheel grain.
Although, the grain geometry was successfully created, further
development to ensure the elimination of voids and cracks in the
propellant matrix is necessary.
2.3 Dual extrusion technique
In this technique, the first extruder would be a conventional
heated 3D printer head used for polymer filaments while the
second extruder would be an unheated paste extruder. In order to
implement this technique, a custom multi-extruder 3D printer
will have to be designed and constructed. This technique will
allow printing any grain shape accurately without needing
intricate molds and patterns of a fixed shape. The 3D printed
mold created by the first extruder can be designed to be of any
shape and appropriate strength. The quasi-simultaneous
construction of the mold and pouring of the propellant slurry
would eliminate the possibility of voids or trapped air bubbles
typically associated with the filling process of full sized molds.
Furthermore, the mold could be made of a low melting point
material to reduce the exposure of the propellant to high
temperatures. Candidate materials for this purpose include PLA,
paraffin wax, and other commercially available low temperature
3D printing materials.
2.4 Solvent extrusion technique
This technique is particularly applicable to the ABS-based
propellants where the slow curing HTPB is replaced with ABS,
which can solidify quickly. The similarity between the energetic
nature of HTPB and ABS has been established [ 16 . The
theoretical performance of a rocket utilizing ABS-based
propellant was estimated using NASA CEA code [17 instead of
conventional APCP. The chemical formulae and the heat of
formation for both ABS and HTPB were obtained from the
literature [16 . The chamber pressure for this hypothetical rocket
was assumed 20 bar and complete expansion of the combustion
products was assumed to occur in an infinite area combustor. The
vacuum specific impulse for a rocket operating on a
stoichiometric mixture of AP-HTPB was found to be 210.2 s,
while the ABS-based propellant with a AP:ABS molar ratio of
4.05:1 yielded a vacuum specific impulse of 188.85 s, which is
comparable to the conventional propellant case.
In addition to being a thermoplastic, ABS is also soluble in
acetone, and butanone. This method may be implemented
through fewer modifications to the existing printers without a
heated extruder. Solvent extrusion technique attempts to create
the “liquid in the nozzle and solid on the build plate” condition
with AP based compositions. The combination of AP, ABS, and
a suitable solvent may be optimized such that the resulting slurry
will remain in liquid phase within the extrusion nozzle while
exposure to ambient air after extrusion will allow evaporation of
the solvent and resulting AP-ABS structure will form a
composite propellant grain.
Implementing this technique requires investigation into the
rheological and evaporative properties of AP-ABS-solvent
combinations. The ratio of mixing will have to be optimized for
obtaining the correct properties such as viscosity of the semi-
liquid mixture and short enough solidification time. As this
approach adds the novelty of using a new binder system for AP
based composite, a study into reaction of kinetics of the new
combination will also need to be carried out.
Preliminary study was conducted with AP-ABS-acetone
mixtures, which form a slurry. The slurry contained 1.151 gram
ABS, 6 gram AP, and 5 ml Acetone. AP and ABS were mixed in
stoichiometric ratio and acetone acted as the solvent. This slurry
was subsequently extruded through the paste extruder to create
a layer of AP-ABS propellant in the shape of a propellant grain.
However, due to the low boiling point of acetone, significant
amount of slurry was solidifying at the nozzle of the syringe
leading to blockage. This prevented the printing of a proper
propellant grain. Future studies may use butanone instead of
acetone in order to alleviate this problem.
3 Conclusions and future scope of work
So far, the proposed study was focused on establishing the
feasibility of 3D printing technique for composite propellant
manufacture. The work done so far has given valuable insights
into the problem at hand. The short term objective of the study
viz. designing, assembling, and testing of simple hardware
related to 3D printer capable of printing conventional AP-HTPB
based composite propellants was accomplished. Theoretical
calculations comparing the performance of ABS based
composite propellants with conventional APCP were also carried
out.
Although, direct printing of APCP using 3D printing technique
was found to be impractical at this stage, the advantages of 3D
printing technique may be utilized through other techniques. The
utility of 3D printing technique for rapidly creating intricate
molds for complex grain shapes was established by 3D printing
simple grain molds and successfully casting small rocket grains.
The solvent extrusion technique could not be implemented due
to rapid evaporation of acetone solvent.
In conclusion, the study shows that 3D printing techniques
demonstrate encouraging prospects for advantageous and
successful application towards manufacture of composite
propellants.
Future scope of work includes further development with the pre-
printed molds. This area demands an investigation into proper
method of filling the mold, propellant curing, and separation of
the mold and the propellant. The development of a dual extruder
printer is the primary requirement for implementing the quasi-
simultaneous printing of mold and the propellant while the
solvent extrusion technique requires a study into rheology and
chemical kinetics of various solvent-based compositions.
The combustion characterization of these propellants through
burning rate measurement, calorimetry, and thrust measurements
is also a part of the future scope of work.
5 Acknowledgment
This work was financially supported by BK21 PLUS program at
the Department of Mechanical and Aerospace Engineering,
Seoul National University. Additional support came from
Advanced Research Center Program (NRF-
2013R1A5A1073861) contracted through Advanced Space
Propulsion Research Center at Seoul National University.
[1 F. Dong-Hui, H.F. Yang, Z. Wei-Hua, Proc. Inst. Mech. Eng.
Part G J. Aerosp. Eng. 228(7) (2014) 1156–1170.
[2 H.L. Archer Jr, U.S. Patent No. 6,431,072. 13 Aug. 2002.
[3 M. Golafshani, M. Farshchi, H. Ghassemi, J. Propuls. Power,
18(1) (2002) 123–130.
[ 4 J. Fuller, D. Ehrlich, P. Lu, R. Jansen, J. Hoffman,
Advantages of Rapid Prototyping for Hybrid Rocket Motor Fuel
Grain Fabrication, 47th AIAA/ASME/SAE/ASEE Joint
Propulsion Conference, 2011, pp. 1–10.
[5 S.A. Whitmore, S.D. Walker, D.P. Merkley, M. Sobbi, J.
Propuls. Power. 31 (2015) 1727–1738.
[6 S.A. Whitmore, S.L. Merkley, L. Tonc, S.D. Mathias, J.
Propuls. Power. (2016) 1–11.
[7 A. Derrick, E. Boyer, B. R. McKnight, J. D. DeSain, J. K.
Fuller, K. K. Kuo, B. B. Brady, and T. J. Curtiss, Int. J. Ener. Mat.
Chem. Prop., 13(4) (2014) 287-307.
[ 8 C.B. Brown, E. Chewakin, M. Feldman, A. Lima, N.
Lindholm, C. Lipscomb, R. Niedzinski, J. Sobol, Solid
Propellant Additive Manufacturing ( SPAM ), Project Report,
University of Colorado Boulder.
[9 P.A. Cattani, T.J. Fleck, J.F. Rhoads, S.F. Son, I.E. Gunduz,
Applications of Additive Manufacturing Techniques in Making
Energetic Materials The Summer Undergraduate Research
Fellowship (SURF) Symposium, 4 August 2016, Purdue
University, West Lafayette, Indiana, USA.
References
[10 T.S. Elliott, B. Jenkins, R. Zeineldin, J. Johnson, M. Simons,
J. Godfrey, Additive Manufacturing of Small Scale Rocket Grain
Cartridges with Uniformly Distributed Aluminum Particles”
52nd AIAA/SAE/ASEE Joint Propulsion Conference, 2016, pp.
1–7.
[11 B. Clark, Z. Zhang, G. Christopher, and M. L. Pantoya, J.
Mater. Sci., 52(2) (2017) 993–1004.
[12 R. Muthiah, V.N. Krishnamurthy, B.R. Gupta, Propellants
Explos. Pyrotech. 21 (1996) 186–192.
[13 J. Pasquale, M.G.M. Marascio, J.A. Månson, D. Pioletti, P.E.
Bourban, Eur. Cells Mater. 32 (2016) 29.
[ 14 W. M. Adel, L. Guo-zhu, Developing a Viscoelastic
Relaxation Model for AP-HTPB Composite Solid Propellant
Based on Experimental Data, 21st AIAA International Space
Planes and Hypersonics Technologies Conference. 2017.
[15 Charlie Garcia available at,
<http://rocketry.mit.edu/2017/04/100-3d-printed-solid-rocket-
motor/>
[16 S. A. Whitmore, Z. W. Peterson, and S. D. Eilers, Analytical
and Experimental Comparisons of HTPB and ABS as Hybrid
Rocket Fuels, 47th AIAA/ASME/SAE/ASEE Joint Propulsion
Conference, 2011 1–48.
[ 17 Gordon, S. and B.J. McBride, Computer program for
calculation of complex chemical equilibrium compositions and
applications. 1996.
11th Asia-Pacific Conference on Combustion,
The University of Sydney, NSW Australia
10th -14th December 2017.
Assessment of 3D printing technology for potential application towards manufacturing
composite propellants
Anirudha Ambekar1 and Jai-ick Yoh1
1Department of Mechanical and Aerospace Engineering, Seoul National University
Seoul, 151-742, Korea
Abstract
Ammonium perchlorate based solid composite propellants are
conventionally manufactured by a casting process. The casting
of propellants is highly resource intensive and demands a shaped
mold for each grain shape to be casted. This limits the number
of grain shapes that can be tested with various propellant
compositions. As the grain shape directly affects the
performance of a propellant charge, innovative grain geometries
could provide significant boost in performance. 3D printing
techniques are a subset of additive manufacturing or rapid
prototyping and provide the capability of quick and economical
manufacture. Thus, application of these techniques for
composite propellant manufacture has the potential to allow the
study of parametric variation of propellant shapes with ease. This
article presents an exploratory study aimed at application of 3D
printing techniques for manufacturing composite propellants.
1 Introduction
Solid composite propellants are prominent amongst the range of
available energetic materials due to their high energy density,
simplicity, and relative safety. The conventional method of solid
rocket motor manufacturing involves casting of a slurry
containing oxidizer, fuel, binder, and curing agents into a mold.
This technique relies on molds and shaped patterns to create the
grain shape, which subsequently determines the thrust profile for
a given rocket. Furthermore, longitudinally varying grain
geometry has been proposed [1 , 2 , 3 for improved grain
performance. However, the process of creating these molds and
patterns is costly and time consuming. Thus, production and
testing novel grain patterns is considerably resource intensive.
This is a significant limitation in parametric design, optimization,
and testing of solid rocket propellants.
In contrast to conventional casting, additive manufacturing (AM)
or 3D printing is inherently capable of a rapid design and
manufacturing cycle irrespective of the geometric complexity of
objects to be manufactured. In typical 3D printing process, three-
dimensional objects are created by successive deposition of
layers of a given material, which is typically a thermoplastic or
a UV hardening resin. Fused deposition modeling (FDM) and
selective laser sintering (SLS) are two AM techniques, which
have found widespread usage in many fields. The application of
AM technology to solid rocket propellants would provide greater
freedom for testing multiple grain patterns, novel compositions,
and optimization of solid rocket motors.
Previously, the FDM technology has been used for fabrication of
hybrid rocket grain by Fuller et al. [4 , Whitmore et al. [5, 6 ,
and Derrick et al. [7 . While, sugar-KNO3 based composite
propellants were manufactured using the SLS technique by
Brown et al. [8 . Furthermore, Cattani et al. [9 have recently
reported a preliminary study regarding printing energetic
composite filaments to be used for 3D printing.
1.1 Basics of 3D printing
The term 3D printing is most commonly used to refer to fused
deposition modelling. In this technique, a thermoplastic polymer
such as acrylonitrile butadiene styrene (ABS) and polylactic acid
(PLA) in the form of a filament is heated to its melting point and
pushed through a heated nozzle. The movement of the nozzle is
controlled through a computer and molten material exiting the
nozzle is laid on a plate to create desired shape. The
thermoplastic laid on the plate cools rapidly, below the glass
transition temperature of the polymer, and acquires a solid form.
The repeated extrusion and controlled nozzle movement is used
to build successive layers of plastic to create desired object. The
key requirement for the correct function of a FDM based 3D
printer lies in keeping the thermoplastic “liquid in the nozzle and
solid on the build plate”.
1.2 Objective
The objective of the current study may be stated as assessing
simple 3D printing technology for manufacturing ammonium
perchlorate composite propellants (APCP). The techniques
envisaged here seek to replace the conventional casting method
and may provide several advantages such as relatively quick
design and fabrication of any grain shape, rapid testing with
novel compositions, reduced cost due to due reduced tooling,
scalability, and accuracy of geometrical patterns, and possibility
of creating functionally graded propellants. The 3D printing
techniques can potentially also create grains with longitudinally
varying geometry.
In addition to being the most common material used for 3D
printing, ABS has been considered as a fuel for hybrid [10 as
well as composite propellants [11 . Current study conducts a
theoretical assessment of the performance of an ABS based
propellant with conventional APCP and proposes a fabrication
technique for such a propellant.
2 Potential techniques of 3D printing APCP
The origin of this study was merely based on the notion that 3D
printers may be used for composite propellant manufacture. The
study in this initial stage has been largely exploratory with
significant literature review and various trials to ascertain
viability of future scope.
Corresponding author. Fax: +82-2-882-1507
E-mail address: [email protected]
A commercial FDM printer (Ecubmaker fantasy II) shown in Fig.
1 was utilized for this study in conjunction with slicing software
Cura 15.04 and 3D modelling software freeCAD version 0.16.
Figure 1: Ecubmaker fantasy II FDM 3D printer with assortment
of components.
The potential techniques, which may be used to manufacture
APCP with a modified 3D printer, include direct printing with
AP-HTPB slurry, 3D printing of molds, dual extrusion technique,
and solvent extrusion technique. Following paragraphs discuss
each of these methods in detail.
2.1 Direct printing with AP-HTPB slurry
Typical composite propellants consist of the oxidizer ammonium
perchlorate (AP), aluminium particles as fuel, the binder
hydroxyl-terminated polybutadiene (HTPB), and certain curing
agents. The ingredients are typically mixed in batch process and
the resulting slurry is cast into moulds for curing. The initial
viscosity of the slurry [ 12 is similar to that of molten
thermoplastic [13 .
An attempt was made to use the 3D printing technology for
directly printing the grain shape with the propellant slurry. The
3D printer was modified to interface with a paste extruder. The
paste extruder was fabricated in-house using ABS thermoplastic
and the 3D printer. Figure 2 shows different views of the paste
extruder assembly spate and mounted on the 3D printer. The
original design of the paste extruder was tweaked to accept
standard 5 ml syringes which would hold the propellant slurry.
Figure 2: Paste extruder for APCP slurry printing.
However, as the curing time for HTPB bonded propellants is
significantly longer [14 , the printed shape of the grain was not
maintained. Figure 3 shows an attempt of printing the wagon
wheel grain with AP-HTPB propellants mixed in 75:25 ratio.
However, the shape of the profile could not be maintained due to
low viscosity of the propellant composition at this stage of
curing.
Figure 3: A trial print of wagon-wheel grain geometry with 75:25
AP-HTPB slurry showing issues due to low viscosity and high
curing time.
Therefore, due to the long curing times AP-HTPB based
composite propellants cannot satisfy the “liquid in the nozzle and
solid on the build plate” requirements and use of molds was
deemed necessary.
2.2 3D printing of molds
This method provides a simple approach wherein the mold of the
desired shape is pre-printed using a standard 3D printing
technique. The 3D printing process of the mold provides the
opportunity of rapid manufacture of intricate core shapes
without the need of complex tooling. The typical 3D printing
materials such as ABS and PLA may be utilized for this purpose.
Figure 4 shows the 2D and 3D model as well as samples
fabricated from ABS plastic for a simple star grain designated
‘A’ and a helical star grain ‘B’.
Figure 4: 2D cross-section of a star grain, 3D model a helical star
grain, and samples fabricated from ABS plastic.
The fabrication of complex helical geometry was rendered easily
with the 3D printing method. Thus, establishing the utility of this
method for creating complex grain geometry. With appropriate
design process determining the various dimensions of the mold,
sufficient mechanical strength can be ensured.
The central core, forming the internal geometry of the propellant
grain, may be designed to be removable through techniques such
as melting and solvent dissolution or it could be designed to be
burnt in place with the AP-HTPB propellant. The outer layer of
the mold may be integrated into or function as a part of the motor
casing similar to recently 3D printed rocket motor [15 .
The technique of 3D printed molds was implemented with two
simplified geometries viz. wagon wheel and plane cylinder. The
outer diameter of the wagon wheel grain was 30 mm with
minimum web thickness of approximately 4 mm and a thickness
of 5 mm. the end burning plane cylindrical grain had an outer
diameter of approximately 18 mm and height of 8 mm. A hand-
mixed composition with AP-HTPB-IPDI in the proportion of
77%:20.5%:2.5% was manually filled in these molds. The filled
molds were cured at 60 ° for 8 days and the cured propellant was
separated from the mold by cutting. The resulting sample grains
have been shown in Fig. 5.
(a) (b)
Figure 5: (a) Cylindrical grain (b) wagon wheel grain.
Although, the grain geometry was successfully created, further
development to ensure the elimination of voids and cracks in the
propellant matrix is necessary.
2.3 Dual extrusion technique
In this technique, the first extruder would be a conventional
heated 3D printer head used for polymer filaments while the
second extruder would be an unheated paste extruder. In order to
implement this technique, a custom multi-extruder 3D printer
will have to be designed and constructed. This technique will
allow printing any grain shape accurately without needing
intricate molds and patterns of a fixed shape. The 3D printed
mold created by the first extruder can be designed to be of any
shape and appropriate strength. The quasi-simultaneous
construction of the mold and pouring of the propellant slurry
would eliminate the possibility of voids or trapped air bubbles
typically associated with the filling process of full sized molds.
Furthermore, the mold could be made of a low melting point
material to reduce the exposure of the propellant to high
temperatures. Candidate materials for this purpose include PLA,
paraffin wax, and other commercially available low temperature
3D printing materials.
2.4 Solvent extrusion technique
This technique is particularly applicable to the ABS-based
propellants where the slow curing HTPB is replaced with ABS,
which can solidify quickly. The similarity between the energetic
nature of HTPB and ABS has been established [ 16 . The
theoretical performance of a rocket utilizing ABS-based
propellant was estimated using NASA CEA code [17 instead of
conventional APCP. The chemical formulae and the heat of
formation for both ABS and HTPB were obtained from the
literature [16 . The chamber pressure for this hypothetical rocket
was assumed 20 bar and complete expansion of the combustion
products was assumed to occur in an infinite area combustor. The
vacuum specific impulse for a rocket operating on a
stoichiometric mixture of AP-HTPB was found to be 210.2 s,
while the ABS-based propellant with a AP:ABS molar ratio of
4.05:1 yielded a vacuum specific impulse of 188.85 s, which is
comparable to the conventional propellant case.
In addition to being a thermoplastic, ABS is also soluble in
acetone, and butanone. This method may be implemented
through fewer modifications to the existing printers without a
heated extruder. Solvent extrusion technique attempts to create
the “liquid in the nozzle and solid on the build plate” condition
with AP based compositions. The combination of AP, ABS, and
a suitable solvent may be optimized such that the resulting slurry
will remain in liquid phase within the extrusion nozzle while
exposure to ambient air after extrusion will allow evaporation of
the solvent and resulting AP-ABS structure will form a
composite propellant grain.
Implementing this technique requires investigation into the
rheological and evaporative properties of AP-ABS-solvent
combinations. The ratio of mixing will have to be optimized for
obtaining the correct properties such as viscosity of the semi-
liquid mixture and short enough solidification time. As this
approach adds the novelty of using a new binder system for AP
based composite, a study into reaction of kinetics of the new
combination will also need to be carried out.
Preliminary study was conducted with AP-ABS-acetone
mixtures, which form a slurry. The slurry contained 1.151 gram
ABS, 6 gram AP, and 5 ml Acetone. AP and ABS were mixed in
stoichiometric ratio and acetone acted as the solvent. This slurry
was subsequently extruded through the paste extruder to create
a layer of AP-ABS propellant in the shape of a propellant grain.
However, due to the low boiling point of acetone, significant
amount of slurry was solidifying at the nozzle of the syringe
leading to blockage. This prevented the printing of a proper
propellant grain. Future studies may use butanone instead of
acetone in order to alleviate this problem.
3 Conclusions and future scope of work
So far, the proposed study was focused on establishing the
feasibility of 3D printing technique for composite propellant
manufacture. The work done so far has given valuable insights
into the problem at hand. The short term objective of the study
viz. designing, assembling, and testing of simple hardware
related to 3D printer capable of printing conventional AP-HTPB
based composite propellants was accomplished. Theoretical
calculations comparing the performance of ABS based
composite propellants with conventional APCP were also carried
out.
Although, direct printing of APCP using 3D printing technique
was found to be impractical at this stage, the advantages of 3D
printing technique may be utilized through other techniques. The
utility of 3D printing technique for rapidly creating intricate
molds for complex grain shapes was established by 3D printing
simple grain molds and successfully casting small rocket grains.
The solvent extrusion technique could not be implemented due
to rapid evaporation of acetone solvent.
In conclusion, the study shows that 3D printing techniques
demonstrate encouraging prospects for advantageous and
successful application towards manufacture of composite
propellants.
Future scope of work includes further development with the pre-
printed molds. This area demands an investigation into proper
method of filling the mold, propellant curing, and separation of
the mold and the propellant. The development of a dual extruder
printer is the primary requirement for implementing the quasi-
simultaneous printing of mold and the propellant while the
solvent extrusion technique requires a study into rheology and
chemical kinetics of various solvent-based compositions.
The combustion characterization of these propellants through
burning rate measurement, calorimetry, and thrust measurements
is also a part of the future scope of work.
5 Acknowledgment
This work was financially supported by BK21 PLUS program at
the Department of Mechanical and Aerospace Engineering,
Seoul National University. Additional support came from
Advanced Research Center Program (NRF-
2013R1A5A1073861) contracted through Advanced Space
Propulsion Research Center at Seoul National University.
[1 F. Dong-Hui, H.F. Yang, Z. Wei-Hua, Proc. Inst. Mech. Eng.
Part G J. Aerosp. Eng. 228(7) (2014) 1156–1170.
[2 H.L. Archer Jr, U.S. Patent No. 6,431,072. 13 Aug. 2002.
[3 M. Golafshani, M. Farshchi, H. Ghassemi, J. Propuls. Power,
18(1) (2002) 123–130.
[ 4 J. Fuller, D. Ehrlich, P. Lu, R. Jansen, J. Hoffman,
Advantages of Rapid Prototyping for Hybrid Rocket Motor Fuel
Grain Fabrication, 47th AIAA/ASME/SAE/ASEE Joint
Propulsion Conference, 2011, pp. 1–10.
[5 S.A. Whitmore, S.D. Walker, D.P. Merkley, M. Sobbi, J.
Propuls. Power. 31 (2015) 1727–1738.
[6 S.A. Whitmore, S.L. Merkley, L. Tonc, S.D. Mathias, J.
Propuls. Power. (2016) 1–11.
[7 A. Derrick, E. Boyer, B. R. McKnight, J. D. DeSain, J. K.
Fuller, K. K. Kuo, B. B. Brady, and T. J. Curtiss, Int. J. Ener. Mat.
Chem. Prop., 13(4) (2014) 287-307.
[ 8 C.B. Brown, E. Chewakin, M. Feldman, A. Lima, N.
Lindholm, C. Lipscomb, R. Niedzinski, J. Sobol, Solid
Propellant Additive Manufacturing ( SPAM ), Project Report,
University of Colorado Boulder.
[9 P.A. Cattani, T.J. Fleck, J.F. Rhoads, S.F. Son, I.E. Gunduz,
Applications of Additive Manufacturing Techniques in Making
Energetic Materials The Summer Undergraduate Research
Fellowship (SURF) Symposium, 4 August 2016, Purdue
University, West Lafayette, Indiana, USA.
References
[10 T.S. Elliott, B. Jenkins, R. Zeineldin, J. Johnson, M. Simons,
J. Godfrey, Additive Manufacturing of Small Scale Rocket Grain
Cartridges with Uniformly Distributed Aluminum Particles”
52nd AIAA/SAE/ASEE Joint Propulsion Conference, 2016, pp.
1–7.
[11 B. Clark, Z. Zhang, G. Christopher, and M. L. Pantoya, J.
Mater. Sci., 52(2) (2017) 993–1004.
[12 R. Muthiah, V.N. Krishnamurthy, B.R. Gupta, Propellants
Explos. Pyrotech. 21 (1996) 186–192.
[13 J. Pasquale, M.G.M. Marascio, J.A. Månson, D. Pioletti, P.E.
Bourban, Eur. Cells Mater. 32 (2016) 29.
[ 14 W. M. Adel, L. Guo-zhu, Developing a Viscoelastic
Relaxation Model for AP-HTPB Composite Solid Propellant
Based on Experimental Data, 21st AIAA International Space
Planes and Hypersonics Technologies Conference. 2017.
[15 Charlie Garcia available at,
<http://rocketry.mit.edu/2017/04/100-3d-printed-solid-rocket-
motor/>
[16 S. A. Whitmore, Z. W. Peterson, and S. D. Eilers, Analytical
and Experimental Comparisons of HTPB and ABS as Hybrid
Rocket Fuels, 47th AIAA/ASME/SAE/ASEE Joint Propulsion
Conference, 2011 1–48.
[ 17 Gordon, S. and B.J. McBride, Computer program for
calculation of complex chemical equilibrium compositions and
applications. 1996.