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A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

This SAE standard establishes the minimum construction and performance requirements for a combination cable consisting of 9 conductors and 2 twisted pairs for use on trucks, trailers, and dollies. The cable includes power, ground and 2 jacketed/unshielded twisted paired signal circuits. This standard will be used in conjunction with the SAEJ XXXX “13 Conductor Electrical Connector (Plug and Receptacle) between Towing Vehicle and Trailer”. The standard will also include the test procedures, design and performance requirements for the cable.

Three-component Particle Image Velocimetry (3D PIV) is a fluid velocity measurement technique that has evolved from the laboratory to become a method appropriate for use in large-scale wind tunnel testing. An example application of 3D PIV in a wind tunnel test is described. The PIV technique was applied to characterize the wake of The Ground Transportation System (GTS) model developed for the Department of Energy (DOE) Heavy Vehicle Drag Reduction (HVDR) program. The test was performed in the Ames/Army 7×10 foot wind tunnel. The objective of the PIV measurements was to validate the HVDR computational fluid dynamics code. The PIV method and PIV system are described. Sample truck wake data with and without boattail attachments are shown. 3D PIV system successfully captured the effects of the boattails on the truck wake.

Coated refractory metals, coated and alloyed graphites, hafnium-tantalum alloys, refractory borides, and stabilized zirconias are considered for the 3600–4000 F high-velocity air environment. Only refractory borides and stabilized zirconias are indicated as offering long duration and reuse capabilities for such high-temperature utilization. Iridium, as coatings on substrates of either graphites or refractory metals, appears attractive for shorter times (less than 1 hr). Environmental evaluation and the need for a theoretical framework to enable the prediction of performance data for such materials are indicated to be major problems facing users and suppliers.

A 500 hours endurance test was performed with a heavy-duty engine (Euro IV); MAN type D 0836 LFL 51 equipped with a PM-Kat®. As fuel 100% biodiesel was used that met the European specification EN 14214. The 500 hours endurance test included both the European stationary and transient cycle (ESC and ETC) as well as longer stationary phases. During the test, regulated emissions (carbon monoxide, nitrogen oxides, hydrocarbons and particulate matter), the particle number distribution and the aldehydes emission were continuously measured. For comparison, tests with fossil diesel fuel were performed before and after the endurance test. During the endurance test, the engine was failure-free for 500 hours with the biogenic fuel. There were almost no differences in specific fuel consumption during the test, but the average exhaust gas temperature increased by about 15°C over the time. Emissions changed only slightly during the test.

Flight control technology for 8000 psi has emerged almost simultaneously with new fire-resistant hydraulic fluids, such as MIL-H-83282 and CTFE. A proliferation of industry recommendations has resulted in a wide variety of mechanisms for solving associated actuator design problems, including tighter clearances, special seals, finishes, materials, and many others. As there are few common agreements on the issues, an extensive three-phase test program was undertaken to attempt to corroborate some of these approaches or suggest others that may be better or more cost effective.

A hydrogen economy is an increasingly popular solution to lower global carbon dioxide emissions. Previous research has been focused on the economic conditions necessary for hydrogen to be cost competitive, which tends to neglect the effectiveness of greenhouse gas mitigation for the very solutions proposed. The holistic carbon footprint assessment of hydrogen production, distribution, and utilization methods, otherwise known as “well-to-wheels” carbon intensity, is critical to ensure the new hydrogen strategies proposed are effective in reducing global carbon emissions. When looking at these total carbon intensities, however, there is no single clear consensus regarding the pathway forward. When comparing the two fundamental technologies of steam methane reforming and electrolysis, there are different scenarios where either technology has a “greener” outcome.

As mission length and the number and complexity of payload experiments increase, so does the probability of thermodegradation contingencies (e.g. fire, chemical release and/or smoke from overheated components or burning materials), which could affect mission success. When a thermodegradation event occurs on board a spacecraft, potentially hazardous levels of toxic gases could be released into the internal atmosphere. Experiences on board the Space Shuttle have clearly demonstrated the possibility of small thermodegradation events occurring during even relatively short missions. This paper will describe the Combustion Products Analyzer (CPA), which is being developed under the direction of the Toxicology Laboratory at Johnson Space Center to provide necessary data on air quality in the Shuttle following a thermodegradation incident.

Both humans and onboard radiosensitive systems (electronics, materials, payloads and experiments) are exposed to the deleterious effects of the harsh space radiations found in the space environment. The purpose of this paper is to present the space radiation environment extended to deep space based on environment models for the moon, Mars, Jupiter, and Saturn and compare these radiation environments with the earth's radiation environment, which is used as a comparative baseline. The space radiation environment consists of high-energy protons and electrons that are magnetically “trapped” in planetary bodies that have an intrinsic magnetic field; this is the case for earth, Jupiter, and Saturn (the moon and Mars do not have a magnetic field). For the earth this region is called the “Van Allen belts,” and models of both the trapped protons (AP-8 model) and electrons (AE-8 model) have been developed.

Nickel-5 Aluminum (95 % Nickel-5 % Aluminum) is widely used in the aircraft engine industry. The excellent adhesive and cohesive strength of the coating, oxidation resistance and machinability make it an ideal material as both a bond coat for subsequent topcoats and as a build up material for dimensional restoration of worn or mismachined components. Plasma spraying has traditionally been the thermal spray process used to apply nickel aluminum, and the technical properties and performance characteristics are well documented. More recently, wire arc sprayed nickel aluminum is becoming widely used as an alternative to plasma spraying due to higher bond strengths, reproducibility, better machinability and more favorable economics. This paper presents the results of a testing program designed to compare the technical properties of arc sprayed versus plasma sprayed Nickel-5 Aluminum coatings.

Corrosion problems associated with using titanium fasteners to assemble aluminum airframe structures are reviewed. Data are presented describing the effectiveness of metallic platings and an aluminum filled organic based coating on fasteners to render the titanium-aluminum electrochemical couple inoperative. The aluminum enriched organic coating known as Hi-Kote 1 is shown to be more effective in minimizing corrosive attack on aluminum airframe structure in both saline and acidic environments. The effectiveness of Hi-Kote 1 in corrosion-fatigue tests of fastened aluminum structure is also reported.

Considering the rising cost and diminished availability of 100-octane, low-lead (100 LL) aviation gasoline, owners of aircraft certified for 100 LL may be forced to find an alternative fuel in the near future. This study proposed a blend of 200-proof anhydrous ethanol ($1.70 per gallon) and automotive gasoline ($1.15 per gallon) as a replacement for aviation gasoline ($1.90 per gallon). The research program included materials compatibility tests, Cooperative Fuel Research (CFR) engine tests, static thrust tests, and a flight test to determine the feasibility of such a blend as a fuel for an unmodified aircraft engine. Throughout all tests, blends burned as well as aviation gasoline. The static thrust tests indicated that a blend of 35% ethanol/65% automotive gasoline yielded the maximum thrust output. The materials tests revealed metals to be unaffected by contact with the blend fuel. Fibrous growths were discovered in the blend and in the automotive gasoline samples.

The BSTCA (Battery Section Thermal Control Assembly) is a module of the Columbus MTFF (Man Tended Free Flyer). Electrical power required during eclipse periods, is made available from six nickel hydrogen batteries. A sophisticated multi-radiator configuration, with a hybrid heat pipe network, has evolved. Autonomous control of the assembly heat rejection capability has been achieved by a integrated network of LTHP's (Liquid Trap Heat Pipes) and CCHP's (Constant Conductance Heat Pipes) under the control of a conventional HCU (Heater Control Unit). The process of design selection and verification is discussed, for the BSTCA, with a detailed LTHP component presentation.

A general discussion of the problems resulting from the introduction of contaminated jet turbine fuel into integral fuel tanks and a five-point program designed to eliminate the contamination problem are presented. Some areas covered are: inspection of fuel sources for contamination to prevent contaminants from entering the aircraft fuel system; decontamination of fuel sources; inspection and decontamination of the aircraft fuel system; use of additives for the control of microorganisms; materials and methods, including a simple system for introducing the additives. The good and bad points of all fuel tank sealing and finishing systems presently in use are discussed, and a new finish system completely resistant to degradation by microorganisms is introduced. Simple means of controlling fuel quality entering the aircraft from uncontrolled sources are outlined.

A FRS for grit blasting and plasma spraying is ideally suited for most companies that use the plasma process. FRS brings a capability of diversity to plasma spraying never before available. Different parts with different geometries requiring different coatings can now be grit blasted and plasma sprayed on the same line at will.

Hydrogen has difficulties in handling in a fuel cell vehicle, and has a fault with taking a big space there. The authors have proposed a hydrogen generation system using ammonia as a liquid fuel for fuel-cell electric vehicles. Ammonia has an advantage not to emit greenhouse effect gases because it does not contain a carbon atom. Hydrogen content of ammonia is 17.6 wt% and hydrogen quantity per unit mass is large. Ammonia can be easily dissociated to hydrogen and nitrogen by heating. Therefore, ammonia is an attractive hydrogen supply source for fuel cell vehicles. The ammonia hydrogen generation system of this study consists of a vaporizer, a heat exchanger and a cracking reactor with a separator. Ammonia is heated with the heat exchanger and sent to the cracking reactor, after it is evaporated through the vaporizer from the liquid ammonia. The ammonia is cracked to hydrogen and nitrogen with an appropriate catalyst.

The factors involved in the selection of a quick-disconnect are grouped into the following classifications for the purpose of discussion: (a) Functional considerations. (b) Weight considerations. (c) Environmental performance factors. (d) End fitting types. (e) Additional considerations.

Heat pipes, loop heat pipes and capillary pumped loops are heat transfer devices driven by capillary forces with high-effectiveness & performance, offering high-reliability & flexibility in varying g-environments. They are suitable for spacecraft thermal control where the mass, volume, and power budgets are very limited. The Canadian Space Agency is developing loop heat pipe hardware aimed at understanding the thermal performance of two-phase heat transfer devices and in developing numerical simulation techniques using thermo-hydraulic mathematical models, to enable development of novel thermal control technologies. This loop heat pipe consists of a cylindrical evaporator, compensation chamber, condenser along with vapor and liquid lines, which can be easily assembled/disassembled for test purposes. This laboratory setup is especially designed to enable the visualization of fluid flow and phase change phenomena.

Thermo-mechanical fatigue and natural aging due to environmental conditions are difficult to simulate in an actual test with the advanced fiber-reinforced composites, where their fatigue and aging behavior is little understood. Predictive modeling of these processes is challenging. Thermal cyclic tests take a prohibitively long time, although the strain rate effect can be scaled well for accelerating the mechanical stress cycles. Glass fabric composites have important applications in aircraft and spacecraft structures including microwave transparent structures, impact-resistant parts of wing, fuselage deck and many other load bearing structures. Often additional additively manufactured features and coating on glass fabric composites are employed for thermal and anti-corrosion insulations. In this paper we employ a thermo-mechanical fatigue model based accelerated fatigue test and life prediction under hot to cold cycles.

A method for analyzing cracking in the finish coatings on aircraft composite parts is described. The method is based on a model in which cracking is caused by hygrothermal tensile strain induced by cold and dry conditions, enhanced by creep relaxation of hygrothermal compressive stress from hot wet conditions.