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Browsing ThinkTech by Author "Ababneh, Mohammed"
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Item 3D Printed Thermal Management System for the Next Generation of Gallium Nitride-based Solid State Power Amplifiers(49th International Conference on Environmental Systems, 2019-07-07) Ababneh, Mohammed; Tarau, Calin; Anderson, WilliamCurrent Gallium Nitride (GaN)-based solid state power amplifiers (SSPAs) are limited in their operational capabilities due to the limitations of the overall thermal management system in dissipating the high heat fluxes. However, GaN based SSPAs are desirable for satellite communication due to their superior linearity, built-in redundancy, reliability, power density and energy efficiency as compared to current technologies such as traveling wave tube amplifiers (TWTAs). In order to enable higher power GaN amplifiers and next generation phased arrays, it is critical to reduce the heat flux on the thermal management system by spreading the heat efficiently across a larger area. Aluminum/ammonia constant conductance heat pipes have been a proven technology for spacecraft thermal control for more than 40 years with both high heat transport capability (76 to 254 Watt-m) and reasonably low mass. Unfortunately, ammonia only works up to about 80°C, while the use of high- temperature electronics such as GaN power amplifiers, allows operation up to 150 °C. This further allows significant reduction in radiator size and mass. Advanced Cooling Technologies, Inc. (ACT) is devloping a novel, low-cost and low-mass thermal management system (TMS) which is capable of handling power densities and temperatures of next generation GaN power amplifiers and phased arrays. The design is based on integration of 3D printed vapor chamber and freeze/thaw tolerant titanium-water heat pipes with several novel features designed to ensure cooling of GaN devices during start-up or operation in space (vacuum and zero gravity) as well as earth environments.Item Advanced Passive Thermal eXperiment (APTx) for Warm Reservior Hybrid Wick Variable Conductance Heat Pipes on the International Space Station(48th International Conference on Environmental Systems, 2018-07-08) Tarau, Calin; Ababneh, Mohammed; Anderson, William; Alvarez-Hernandez, Angel; Ortega, Stephania; Farmer, Jeff; Hawkins, RobertAs NASA prepares to further expand human and robotic presence in space, it is well known that spacecraft architectures will be impacted by unprecedented power requirements and thermal environments in deep space. In addition, there is a need to extend the duration of the missions in both cold and hot environments, including cis-lunar and planetary surface excursions. The heat rejection turn–down ratio of the increased thermal loads in the above-mentioned conditions is crucial for minimizing vehicle power needs. Therefore, future exploration activities will have the need of thermal management systems that can provide higher reliability and performance, and power and mass reduction. In an effort to start addressing the current technical gaps in thermal management systems, novel new passive thermal technologies have been selected and tested on the board of the International Space Station (ISS). This testing was performed under the Advanced Passive Thermal eXperiment (APTx) project that is a collaboration between the Johnson Space Center (JSC), Marshall Space Flight Center (MSFC), University of Texas, and Advanced Cooling Technologies, Inc. (ACT) with funding from ISS Technology Demonstration Office at JSC as well as NASA’s Small Business Innovative Research Program. A hybrid-wick copper-Monel-water Variable Conductance Heat Pipe (VCHP) with warm reservoir design that consists of a copper evaporator (with sintered wick), a monel adiabatic section and a condenser both with grooved wick inside was developed and tested successfully on ground. The VCHP worked on the board of the ISS, but at higher temperatures than expected. Hence, a new flight VCHP design is currently under development to mitigate the shortcomings encountered in microgravity. The final paper will include some results and conclusions from the original flight testing and the ground test results for the improved VCHP.Item Analyses of Blue Origin Blue Moon Lunar Landing Descent Engine Plume Effects(2023 International Conference on Environmental Systems, 2023-07-16) Hoey, William; Maxwell, Martin; Alred, John; Soares, Carlos; Ababneh, MohammedPowered landings onto airless bodies like the Moon generate rarefied gas dynamic environments composed of engine plume flows and surface materials including mobilized dusts. These induced atmospheres can cause harmful degradations of spacecraft performance. In particular, lunar dust can cause severe operational problems for human and cargo landing systems, astronauts, and deployed scientific observatories as was observed during the Apollo program. The need to understand and quantify the effects of plume-surface interactions during powered landings onto airless bodies has motivated the development of physics-based modeling approaches at NASA’s Jet Propulsion Laboratory. JPL incorporates inputs from Blue Origin and literature surveys of lunar regolith and applies computational fluid dynamics, direct simulation Monte Carlo, and Lagrangian particle-tracing simulation methodologies to model the plume exhaust flowfields generated by the Blue Moon descent engines during the final meters of landing, as well as the effects of that plume flow in eroding, entraining, and transporting lunar regolith to the descent element. The effects of dust deposition onto thermal control system radiators are of primary interest in this work, but other detrimental effects can include deposition onto landing sensors and optical systems during and after landing; damage induced by dust impact or subsequent abrasion within exposed lander cavities; and the performance degradation of solar arrays and scientific payload instruments. Plume interactions will also result in lunar dust clouds which may obscure visibility during landing, and may cause mechanical erosion of surfaces downstream of the plume-surface interaction.Item Demonstration of Copper-Water Heat Pipes Embedded in High Conductivity (HiK™) Plates in the Advanced Passive Thermal eXperiment (APTx) on the International Space Station(48th International Conference on Environmental Systems, 2018-07-08) Ababneh, Mohammed; Tarau, Calin; Anderson, William; Alvarez-Hernandez, Angel; Ortega, Stephania; Farmer, Jeffrey; Hawkins, RobertCopper-water heat pipes are commonly used for thermal management of electronics systems on earth and aircraft, but have not been used in spacecraft thermal control applications to date, due to the satellite industry’s requirement that any device or system be successfully tested in a microgravity environment prior to adoption. Recently, Advanced Cooling Technologies Inc., (ACT), in coordination with engineers from NASA’s Marshall Space Flight Center (MSFC) and Johnson Space Center (JSC) demonstrated successful flight operation of these heat pipes in low-Earth orbit. The testing was conducted aboard the International Space Station (ISS) under the Advanced Passive Thermal eXperiment (APTx) project, a project to test a suite of passive thermal control devices funded by the ISS Technology Demonstration Office at NASA JSC. The heat pipes were embedded in a high conductivity (HiK™) aluminum base plate and subject to a variety of thermal tests over a temperature range of -10 to 38 ºC for a ten-day period. Results showed excellent agreement with both predictions and ground tests. The HiK™ plate underwent 15 freeze-thaw cycles between -30 and 70 ºC during ground testing, and an additional 14 freeze-thaw cycles during the ISS testing. The following was demonstrated during 10 days of testing on the ISS: 1. Successful operation of the copper-water heat pipes and HiK™ plate 2. Ability of the copper-water heat pipes and HiK™ plate to survive multiple freeze/thaw cycles 3. As-designed heat transport via Copper-water heat pipes. 4. Reliable, repeatable start up of Copper-water heat pipes and HiK™ plate from a frozen state. This paper describes the test hardware, ground and flight test campaign, and discusses the results and conclusions of the testing.Item Design Analysis and Performance testing of a Novel Passive Thermal Management System for Future Exploration Missions(48th International Conference on Environmental Systems, 2018-07-08) Alvarez, Angel; Ortega, Stephania; Farmer, Jeff; Breeding, Shawn; Tarau, Calin; Ababneh, Mohammed; Anderson, WilliamIn response to an announcement of opportunity from the NASA’s Science Mission Directorate (SMD) Discovery Program, the Southwest Research Institute in collaboration with the Aerospace Corporation and the NASA Johnson Space Center (JSC) proposed a lunar lander science mission. The Moon Age and Regolith Explorer (MARE) would use a lunar lander to reach a young, nearside lunar lava flow for the collection and analysis of the lunar soil. This would be used for the determination of the impact history of the inner solar system and the evolution and differentiation of the interiors of one-plate planets. The lunar lander proposed was based on the NASA JSC Morpheus lander vehicle. The thermal environments for the proposed mission were both challenging and unprecedented, since survival of multiple lunar day/night cycles at the south-west region of the Aristarchus plateau were required. Other thermal design challenges included the need of a low mass, simple, robust and reliable thermal management system that would assure the success of the proposed mission. As part of the proposal effort, and leveraging on existing NASA Small Business Innovative Research (SBIR), a completely passive thermal control system concept was used to meet mission requirements. The thermal management system proposed uses a novel type of hybrid grooved and sintered wick variable conductance heat pipe and a high conductivity heat spreader; the thermal management systems tested wer developed by Advanced Cooling Technologies, Inc. (ACT) in Landcaster, Pennsylvania. This publication will present the design, analysis and prototype component and system level performance testing done at NASA JSC.Item High Heat Flux (>50 W/cm^2) Hybrid Constant Conductance Heat Pipes(48th International Conference on Environmental Systems, 2018-07-08) Ababneh, Mohammed; Tarau, Calin; Anderson, William; Fisher, JesseNovel hybrid wick aluminum-ammonia constant conductance heat pipes (CCHPs) are developed to handle heat flux requirements for spacecraft thermal control applications. The 5-10 W/cm^2 heat density limitation of aluminum-ammonia grooved heat pipes has been a fundamental limitation in the current design for space applications. The recently demonstrated >50W/cm^2 capability of the hybrid high heat flux heat pipes provides a realistic means of managing the high heat density anticipated for the next generation space designs. The hybrid wick high heat flux aluminum-ammonia CCHP transported a heat load of 275 Watts with heat flux input of > 50 W/cm^2 and with a thermal resistance of 0.015 ºC/W at 0.1 inch adverse elevation. This demonstrates an improvement in heat flux capability of more than 5 times over the standard axial groove aluminum-ammonia CCHP design.Item Hybrid Heat Pipes for Lunar and Martian Surface and High Heat Flux Space Applications(46th International Conference on Environmental Systems, 2016-07-10) Ababneh, Mohammed; Tarau, Calin; Anderson, William; Farmer, Jeffery; Alvarez-Hernandez, AngelNext generation of polar rovers and equatorial landers is among the immediate NASA planetary applications. These landers and rovers have a Warm Electronics Box (WEB) and a battery, both of which must be maintained in a fairly narrow temperature range. So, a variable thermal link between the WEB and radiator is required. During the day, the thermal link must transfer heat from the WEB to the radiator as efficiently as possible, to minimize the radiator size. On the other hand, the thermal link must be as ineffective as possible during the Lunar night. This will preserve the electronics and battery warm with minimal power, even with the very low heat sink temperature. This variable thermal link can be a variable conductance heat pipe (VCHP) would require hybrid wick to allow liquid return during operation under unfavorable orientation of the evaporator. Also, future spacecraft and instruments developed for NASA's Science Mission Directorate will involve highly integrated electronics, such as for CubeSat/SmallSat. This high density electronics packaging leads to substantial improvement in performance per unit, mass, volume and power. However, it also results in requirement of sophisticated thermal control technology to dissipate the high heat flux generated by these electronics systems. For example, the current incident heat flux for laser diode applications is on the order of 5-10 W/cm2, although this is expected to increase towards 50 W/cm2. This is a severe limitation for the commonly employed axial groove aluminum/ammonia constant conductance heat pipes (CCHPs). Hence, high flux heat acquisition and transport devices are required. The paper reports on the development of VCHPs and CCHPs with a hybrid grooved and sintered wick.