The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform
Sejin Kwon - One of the best experts on this subject based on the ideXlab platform.
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A mixture of hydrogen peroxide and tetraglyme as a green energetic monopropellant
Combustion and Flame, 2019Co-Authors: Hongjae Kang, Sejin KwonAbstract:Abstract An effort is presented to seek a promising candidate for a green energetic monopropellant based on hydrogen peroxide. The novel premixed monopropellant is composed of 90 wt.% H2O2 as the oxidizer and tetraglyme (C10H22O5) as the fuel. Different mixture ratios were prepared by varying the weight percentage of the fuel in the mixture, and the mixtures were named HPM-08 (8 wt.% of fuel), HPM-12 (12 wt.% of fuel), and HPM-20 (20 wt.% of fuel). The theoretical performance of the mixtures was estimated, and their thermostability in air was evaluated via thermogravimetric analysis. A small-scale packed-bed catalytic reactor was utilized to assess the feasibility of the catalytic ignition of HPM-08 with a lanthanum-doped manganese oxide catalyst. Ground hot-firing tests were implemented with an engineering model monopropellant thruster on the scale of 10 N. The demonstrations of the thruster operation using HPM-08 and HPM-12 were successful, but an explosion was caused in the case of HPM-20. A technical speculation suggested that the explosion could be closely related to the phenomenon of detonation. In this study, the configuration of the catalyst bed was regarded as the principal factor in the triggering of detonation in the thruster module. The packed-bed-type catalyst bed containing millimeter-scale pellets may accelerate the phenomenon of deflagration-to-detonation transition, resulting from the rapid compressive heating process based on the superposition of the pressure waves. These results should be taken into account during the design of the catalyst bed in order to utilize particular types of this premixed monopropellant. In addition, a new ignition technique may be applied to prevent the explosion.
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Development of High-Performance Green-Monopropellant Thruster with Hydrogen Peroxide and Ethanol
Journal of Propulsion and Power, 2018Co-Authors: Seungkwan Baek, Woosuk Jung, Hongjae Kang, Sejin KwonAbstract:Green liquid monopropellant thrusters provide an alternative to toxic hydrazine. A premixed liquid monopropellant based on hydrogen peroxide with ethanol blending was suggested to replace hydrazine...
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Preheating characteristics of H2O2 monopropellant thruster using manganese oxide catalyst
Aerospace Science and Technology, 2015Co-Authors: Dongwook Jang, Shinjae Kang, Sejin KwonAbstract:Abstract Preheating characteristics of hydrogen peroxide monopropellant thruster with manganese oxide catalyst were investigated. Monopropellant thruster requires to preheat a catalyst bed for efficient operation in space environment. Optimum preheating temperature of hydrazine monopropellant thruster was well studied. However, preheating characteristics of 90 wt% hydrogen peroxide monopropellant thruster with manganese oxide catalyst are still a subject to research. For this purpose, a 50 N vacuum thrust class monopropellant thruster was employed. The preheating temperature was from 50 °C to 250 °C in increments of 50 °C, and a test in cold start was included as a control group. Their preheating characteristics were expressed in terms of rising time and pressure instability. The results indicate that a significant improvement in rising time and pressure instability was observed until the preheating temperature reached 150 °C. However, in further preheating temperature, the results showed no noteworthy improvements.
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Design, fabrication and thrust measurement of a micro liquid monopropellant thruster
Journal of Micromechanics and Microengineering, 2014Co-Authors: Sejin KwonAbstract:A liquid monopropellant MEMS thruster was designed, fabricated and tested. For application on a nanosatellite for orbit control, a liquid propellant MEMS thruster delivers better performance than a solid thruster. Two issues must be addressed for a liquid monopropellant MEMS thruster: high energy content of the monopropellant to overcome the excessive heat loss associated with the small scale of the thruster, and repeatability of generated thrust force. The present study proposed blending 90 wt% hydrogen peroxide with ethanol at an oxidizer to fuel ratio of 30 to enhance the energy content of the propellant. The thruster structure was constructed using glass layers that were individually patterned by wet etching. The decomposition catalyst was separately prepared by wet impregnation of the active material, Pt, on the gamma alumina pellets and inserted into the thrust chamber before the UV bonding process of the glass layers. The firing test of the assembled MEMS thruster was conducted and thrust was measured both with ethanol blended hydrogen peroxide and pure hydrogen peroxide as a reference monopropellant. The measured thrusts were approximately 30 mN for both 1.7 ml min−1 flow rate of blended hydrogen peroxide and 2.0 ml min−1 flow rate of pure hydrogen peroxide. The measured thrust for 1.7 ml min−1 pure hydrogen peroxide was approximately 24 mN. The measured thrust was 40% less than the design thrust for both Monopropellants. The uncertainty of the thrust was less with blended monopropellant than with pure hydrogen peroxide.
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Design, fabrication and thrust measurement of a micro liquid monopropellant thruster
J Micromechanics and Microengineering, 2014Co-Authors: Jeongmoo Huh, Sejin KwonAbstract:A liq. monopropellant MEMS thruster was designed, fabricated and tested. For application on a nanosatellite for orbit control, a liq. propellant MEMS thruster delivers better performance than a solid thruster. Two issues must be addressed for a liq. monopropellant MEMS thruster: high energy content of the monopropellant to overcome the excessive heat loss assocd. with the small scale of the thruster, and repeatability of generated thrust force. The present study proposed blending 90 wt% hydrogen peroxide with ethanol at an oxidizer to fuel ratio of 30 to enhance the energy content of the propellant. The thruster structure was constructed using glass layers that were individually patterned by wet etching. The decompn. catalyst was sep. prepd. by wet impregnation of the active material, Pt, on the gamma alumina pellets and inserted into the thrust chamber before the UV bonding process of the glass layers. The firing test of the assembled MEMS thruster was conducted and thrust was measured both with ethanol blended hydrogen peroxide and pure hydrogen peroxide as a ref. monopropellant. The measured thrusts were approx. 30 mN for both 1.7 mL min-1 flow rate of blended hydrogen peroxide and 2.0 mL min-1 flow rate of pure hydrogen peroxide. The measured thrust for 1.7 mL min-1 pure hydrogen peroxide was approx. 24 mN. The measured thrust was 40% less than the design thrust for both Monopropellants. The uncertainty of the thrust was less with blended monopropellant than with pure hydrogen peroxide. [on SciFinder(R)]
Keiichi Hori - One of the best experts on this subject based on the ideXlab platform.
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New HAN-based mixtures for reaction control system and low toxic spacecraft propulsion subsystem: Thermal decomposition and possible thruster applications
Combustion and Flame, 2015Co-Authors: Rachid Amrousse, Toshiyuki Katsumi, Noboru Itouyama, Nobuyuki Azuma, Hideshi Kagawa, Keigo Hatai, Hirohide Ikeda, Keiichi HoriAbstract:HAN-based liquid monopropellant has been studied for its possible substitution of hydrazine toxic component. The onset temperature of decomposition was provided by DTA-TG thermal analysis. Moreover, the effect of 5M HNO3and 5M NH2OH addition on catalytic decomposition was also examined. The major products measured by mass spectrometer were N2, NO, N2O, NO2, H2O and NH3. Otherwise, the burning rates of HAN-based Monopropellants were measured from the strand burner videos taken by high speed camera. The effect of methanol addition; as fuel; on the burning rates was demonstrated. On the other hand, HAN-based liquid monopropellant was tested and decomposed in 20N thruster and different catalysts were compared. Honeycomb catalysts were tested instead Shell 405 catalysts, the obtained data demonstrate the improvement of burning reactions and pressure slopes after HAN-based decomposition.
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Chemical engineering study for hydroxylammonium nitrate monopropellant decomposition over monolith and grain metal-based catalysts
Reaction Kinetics Mechanisms and Catalysis, 2014Co-Authors: Rachid Amrousse, Toshiyuki Katsumi, Ahmed Bachar, Rachid Brahmi, Mohamed Bensitel, Keiichi HoriAbstract:The influence of the catalyst support shapes on the performance of liquid monopropellant thrusters was investigated. In the present work, two supports: monolith honeycombs and alumina grains were tested and their relative performances were compared. Ir-monolith catalysts with total metallic contents of 30 wt% in mass were prepared by the wet impregnation method. The characterization of these materials, before and after their use for liquid monopropellant decomposition in a satellite thruster, was performed by measurement techniques of specific surface area, H_2 chemisorption, ICP, SEM and TEM measurements. The catalytic decomposition tests display the best catalytic activity for the grain catalyst (Shell 405) with a complete decomposition of liquid monopropellant, due to a good contact between solid–liquid phases, and monolith catalyst with longer catalyst bed. Moreover, the monolith catalyst leads only to partial liquid monopropellant decomposition, due to injection model and preferential channels through the catalyst bed. The performance of the thruster when using monolith honeycomb and alumina grains as the catalyst bed was evaluated by measuring the product-gas temperatures and pressures at different points of the catalyst bed.
Adam Brand - One of the best experts on this subject based on the ideXlab platform.
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Reduced Toxicity High Performance Monopropellant
2011Co-Authors: Adam BrandAbstract:Abstract : These briefing charts are an overview of reduced toxicity, high performance monopropellant. Performance of hydrazine limits spacecraft payload, range, lifetime and operational response time. The focus is to replace SOTA Hydrazine with Monopropellants based on energy dense ionic liquids.
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Reduced Toxicity, High Performance Monopropellant at the U.S. Air Force Research Laboratory
2010Co-Authors: Tom Hawkins, Adam Brand, Milton Mckay, Michael TinnirelloAbstract:Abstract : Current programs are aiming to develop reduced toxicity monopropellant formulations to replace spacecraft hydrazine monopropellant. The Air Force Research Laboratory's (AFRL's) approach to replacing hydrazine is the synthesis and development of energetic compounds/formulations with substantially less vapor toxicity and superior performance (specific impulse and density). Characterization and testing of these high energy density materials is an essential part of the screening process for viable advanced propellants. Hazardous handling characteristics, undesirable physical properties or unacceptable sensitivity behaviors must also be identified and/or modified to further development by a potential user. AFRL has successfully identified a novel monopropellant (designated AF-M315E) that shows great promise as an avenue toward replacement of hydrazine monopropellant for spacecraft propulsion. Hazard and safety/sensitivity, stability, and toxicity studies have been conducted on the monopropellant and will be described. The results from AF-M315E indicate that a >50% improvement in propulsion system performance over hydrazine is achievable while simultaneously providing a safer environment for the general public, ground personnel, crews and flight participants.
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evaluation of Monopropellants for reusable launch vehicles
2001Co-Authors: Paul F Jones, Tom Hawkins, Adam Brand, Milton Mckay, Stephen L RodgersAbstract:Abstract : Previously, the Air Force has been investigating high performance salt-based, liquid Monopropellants for low thrust spacecraft applications. The focus of this effort has been on finding a reduced toxicity monopropellant with a predicted density performance impulse greater than 50% over hydrazne. During this same period of time, NASA has been investigating reusable launch vehicle (KLV) concepts and has considered using Monopropellants in this application. Anticipating a possible RLV payoff, NASA and the Air Force are working on a trade study to gauge the potential applicability of the salt-based Monopropellants in booster applications. This study will include a performance comparison of salt-based Monopropellants; a list of minimum safety, hazard, and physical property requirements based on operational and logistical support environments for an RLV.
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novel catalysts for non toxic Monopropellants
2001Co-Authors: Ender Savrun, Eckart Schmidt, Adam BrandAbstract:Abstract : Reduced toxicity ionic salt Monopropellants containing hydroxylammonium nitrate (HAN, HO(-)NH3(+)NO3(-)) in highly concentrated aqueous solutions have been proposed as replacements for hydrazine. To be competitive with the rocket performance of hydrazine, HAN-based Monopropellants will have to operate at temperatures above the limit of the state-of-the-art catalyst Shell 405 (l37l degrees centigrade). To realize the benefits of reduced toxicity propellants without a concomitant loss of performance, catalysts and chamber materials capable of withstanding operating temperatures above 1371 degrees centigrade have to be developed. Sienna Technologies, Inc., has successfully demonstrated the feasibility of a family of ceramic-based catalysts that can decompose nontoxic HAN-based liquid Monopropellants, and withstand the high temperature, acidic and steam-rich environment encountered during thruster operations. Several processing techniques were developed to manufacture these carriers and potential catalysts in granular forms that result in reproducible packing densities in packed bed reactors. Rocket engine tests demonstrated that STI-developed catalysts are more active and more durable than any other catalysts tested to date with the hot AFRL-developed ionic salt Monopropellants.
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characterization of reduced toxicity high performance Monopropellants at the u s air force research laboratory
2001Co-Authors: T W Hawkins, Adam Brand, Milton Mckay, Ismail IsmailAbstract:Abstract : Current U.S. Air Force programs are working to develop reduced toxicity monopropellant formulations to replace spacecraft hydrazine monopropellant and exceed the monopropellant performance objective (greater than 50% increase in density impulse) specified by the Integrated High Payoff Rocket Propulsion Technology (IHPRPT) Program. The creation of such Monopropellants can offer considerable cost savings associated with handling and loading, longer spacecraft service life, smaller vehicle design, and heavier payloads. The Air Force Research Laboratory's (AFRL) approach to replacing hydrazine is the development of energetic liquid salt mixtures with substantially less vapor toxicity and superior performance (specific impulse and density). These liquid salt mixtures show promise as one avenue toward replacement of hydrazine monopropellant. During the last year, work has centered on the production and characterization of a few of these reduced toxicity monopropellant formulations. Aside from a low melting point and toxicity, there are a number of properties that are desirable for a monopropellant successor to hydrazine. This report presents the results of tests of specific properties of a new monopropellant (AFN1) that is under investigation by AFRL and compared them to hydrazine. Experimental results are provided for density, vapor toxicity, carbon content of exhaust, melting point, detonability, friction and impact sensitivity, Adiabatic compressibility, thermal stability, critical diameter, viscosity, velocity, and theoretical performance with regard to specific impulse, density, volumetric impulse, and detonation velocity. The report also provides thruster test results for AFN1 and hydrazine in the following areas: theoretical, measured, and efficiency of catalytic decomposition at 64% ammonia dissociation; chamber pressure; throughput; and pulse duration. (6 tables, 2 figures, 5 refs.)
Charles Kappenstein - One of the best experts on this subject based on the ideXlab platform.
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Pulse response times of hydrogen peroxide monopropellant thrusters
45th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2009Co-Authors: Sungyong An, Rachid Brahmi, Charles Kappenstein, Sejin KwonAbstract:The transient behavior of a monopropellant thruster was investigated. Throughout the study, MnO2/Al2O3 was used as the catalyst bed in order to eliminate the influence of the catalyst bed on the transient behavior. Three 50 Newton level test thrusters with different injectors, ullage volumes, and bed sizes were built. H2O2 (90 wt%) was used as the monopropellant in the thrusters and experiments were carried out using these thrusters. The transient characteristics of the thrusters—the ignition delay and the time taken for pressure rise and pressure decay—were determined. Among the injectors considered, the transient characteristics of the shower-head injector are better than those of the spray injector The shower-head injector showed the best performance when a catalyst bed with a small volume was used: the ignition delay was 14 ms; the pressure rise, 108 ms, and the pressure decay, 94 ms.
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catalytic and thermal decomposition of ionic liquid Monopropellants using a dynamic reactor comparison of powder and sphere shaped catalysts
Chemical Engineering and Processing, 2007Co-Authors: Daniel Amariei, Sylvie Rossignol, Laurence Courtheoux, Charles KappensteinAbstract:Abstract A dynamic reactor with mass spectroscopy online product analysis has been used to study the thermal and catalytic decompositions of ionic liquid HAN-based Monopropellants. The activity of different catalysts has been evaluated by determining qualitatively and quantitatively the reaction products. A careful calibration of the expected products detected by the mass spectrometer (MS) (N 2 , O 2 , N 2 O, NO and NO 2 ) has been performed. The analytical results have been supplemented by Raman spectroscopy of the aqueous solutions trapped after the reactor. The thermal and catalytic decomposition of water–HAN (80 wt.%, hydroxylammonium nitrate NH 3 OH + NO 3 − ) mixture gave primary products (major N 2 , medium NO) and secondary products (medium N 2 O and traces NO 2 ). From the data, a reaction mass balance could be proposed, based on the combination of two parallel competitive reactions: 6NH 3 OHNO 3 (aq) = 3N 2 (g) + 2NO(g) + 10H 2 O(g) + 4HNO 3 (g), Δ r H ° = −117.8 kJ HAN mol −1 6NH 3 OHNO 3 (aq) = 2N 2 (g) + 2N 2 O(g) + 10H 2 O(g) + 4HNO 3 (g), Δ r H ° = −121.0 kJ HAN mol −1 The influence of the catalyst shape (powder or spheres) has been followed. The isothermal tests at 50 °C display the best activity for the powder catalyst with a complete decomposition of the HAN solution, due to a good contact between catalyst bed and monopropellant. On the other hand, the sphere-shaped catalyst leads only to a partial HAN decomposition, due to preferential paths through the catalyst bed. The thermal decomposition at 200 °C, leads also to a partial reaction.
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development and test of a miniature hydrogen peroxide monopropellant thruster
42nd AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2006Co-Authors: Carsten Scharlemann, Charles Kappenstein, Rachid Brahmi, M Schiebl, K Marhold, Martin Tajmar, Pierpaolo Miotti, Yann Batonneau, C HunterAbstract:Analysis of present and future missions concluded that a miniaturised hydrogen peroxide monopropellant rocket engine is the optimum solution for the increasing demand for small and low cost propulsion systems for small satellites. The attractiveness of monopropellant thrusters is based on its operational and structural simplicity. Additionally, the utilization of hydrogen peroxide as propellant instead of hydrazine allows the reduction of the overall costs and would qualify such a system as a green propellant propulsion system. The present paper describes the development of a monopropellant thruster utilizing hydrogen peroxide and advanced catalyst beds. The utilization of a monolithic catalyst reduces the pressure loss across the catalyst bed significantly compared to formerly used pellet or gauze catalyst. This allows the use of relative lightweight tank and significantly minimizes the total weight. For Two different catalyst materials have been developed to achieve optimized decomposition. The present paper summarizes the experimental evaluation of the catalysts. Decomposition temperatures of up to 670°C and decomposition efficiencies up to 99% have been achieved. Up to 1.2 kg of hydrogen peroxide has been decomposed by a single catalyst, corresponding to about 1.25 hrs of operation. This is estimated to correspond in vacuum condition to a total delivered total impulse of 1600 Ns. A thrust balance was designed and built. Preliminary thrust measurements under atmospheric conditions have shown that the laboratory model can generate thrust in a range of at least 50 to 550 mN.
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design and use of a batch reactor for catalytic decomposition of different Monopropellants
36th AIAA ASME SAE ASEE Joint Propulsion Conference and Exhibit, 2000Co-Authors: Rachel Eloirdi, Sylvie Rossignol, Michael Chauveau, Charles Kappenstein, Daniel Duprez, Nicolas PilletAbstract:The use of pure hydrazine as monopropellant for small thrusters suffers some disadvantage due to the toxicity of this molecule associated with its rather high vapor pressure at room temperature. With the aim to replace hydrazine by less toxic but just as efficient propellant, we have developed a constant volume computerized batch reactor which permit to study different Monopropellants and their associated catalysts. This reactor can be used as a screening reactor and its main advantages are: easy use, fast change of catalyst or propellant, very limited consumption of propellant or catalyst, simultaneous recording of reactor pressure, catalyst and gas phase temperatures. The catalyst can be preheated and the working pressure is between vacuum and 2 bars. The main parameters that can be obtained are the efficiency and the rate of the catalytic decomposition as well as the ignition delay and the onset temperature. Three propellants have been checked: pure hydrazine, hydrogen peroxide and a HAN-TEAN-water mixture; they display similar rates and ignition delays but the HAN-based propellant needs higher initial temperature and leads to the parallel formation of solid products. For a specific propellant, this reactor permits to classify different catalytic beds before further investigations.
Rachid Amrousse - One of the best experts on this subject based on the ideXlab platform.
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New HAN-based mixtures for reaction control system and low toxic spacecraft propulsion subsystem: Thermal decomposition and possible thruster applications
Combustion and Flame, 2015Co-Authors: Rachid Amrousse, Toshiyuki Katsumi, Noboru Itouyama, Nobuyuki Azuma, Hideshi Kagawa, Keigo Hatai, Hirohide Ikeda, Keiichi HoriAbstract:HAN-based liquid monopropellant has been studied for its possible substitution of hydrazine toxic component. The onset temperature of decomposition was provided by DTA-TG thermal analysis. Moreover, the effect of 5M HNO3and 5M NH2OH addition on catalytic decomposition was also examined. The major products measured by mass spectrometer were N2, NO, N2O, NO2, H2O and NH3. Otherwise, the burning rates of HAN-based Monopropellants were measured from the strand burner videos taken by high speed camera. The effect of methanol addition; as fuel; on the burning rates was demonstrated. On the other hand, HAN-based liquid monopropellant was tested and decomposed in 20N thruster and different catalysts were compared. Honeycomb catalysts were tested instead Shell 405 catalysts, the obtained data demonstrate the improvement of burning reactions and pressure slopes after HAN-based decomposition.
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Chemical engineering study for hydroxylammonium nitrate monopropellant decomposition over monolith and grain metal-based catalysts
Reaction Kinetics Mechanisms and Catalysis, 2014Co-Authors: Rachid Amrousse, Toshiyuki Katsumi, Ahmed Bachar, Rachid Brahmi, Mohamed Bensitel, Keiichi HoriAbstract:The influence of the catalyst support shapes on the performance of liquid monopropellant thrusters was investigated. In the present work, two supports: monolith honeycombs and alumina grains were tested and their relative performances were compared. Ir-monolith catalysts with total metallic contents of 30 wt% in mass were prepared by the wet impregnation method. The characterization of these materials, before and after their use for liquid monopropellant decomposition in a satellite thruster, was performed by measurement techniques of specific surface area, H_2 chemisorption, ICP, SEM and TEM measurements. The catalytic decomposition tests display the best catalytic activity for the grain catalyst (Shell 405) with a complete decomposition of liquid monopropellant, due to a good contact between solid–liquid phases, and monolith catalyst with longer catalyst bed. Moreover, the monolith catalyst leads only to partial liquid monopropellant decomposition, due to injection model and preferential channels through the catalyst bed. The performance of the thruster when using monolith honeycomb and alumina grains as the catalyst bed was evaluated by measuring the product-gas temperatures and pressures at different points of the catalyst bed.