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Viewing 1 to 30 of 1325
2010-10-25
Journal Article
2010-01-2091
Michael J. Lance, C. Scott Sluder, Samuel Lewis, John Storey
Exhaust gas recirculation (EGR) cooler fouling has become a significant issue for compliance with nitrogen oxides (NOx) emissions standards. In order to better understand fouling mechanisms, eleven field-aged EGR coolers provided by seven different engine manufacturers were characterized using a suite of techniques. Microstructures were characterized using scanning electron microscopy (SEM) and optical microscopy following mounting the samples in epoxy and polishing. Optical microscopy was able to discern the location of hydrocarbons in the polished cross-sections. Chemical compositions were measured using thermal gravimetric analysis (TGA), differential thermal analysis (DTA), gas chromatography-mass spectrometry (GC-MS), x-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD). Mass per unit area along the length of the coolers was also measured.
2010-10-25
Journal Article
2010-01-2090
Michael Marr, James S. Wallace, Silvio Memme, Sanjeev Chandra, Larry Pershin, Javad Mostaghimi
Surface temperature and heat flux were measured in a single cylinder SI engine piston when uncoated and with two different surface coatings: a metal TBC and YSZ. Average heat flux into the piston substrate was 33 % higher with the metal TBC and unchanged with the YSZ relative to the uncoated surface. The increase with the metal TBC was attributed to its surface roughness. However, the metal TBC and YSZ reduced peak heat flux into the substrate surface by 69 % and 77 %, respectively.
2011-04-12
Technical Paper
2011-01-0155
Vinod Shigarkanthi, Vijayakanthan Damodaran, Deepak Soundararaju, Kannan Kanniah
Aero shutter is device used for controlling air flow through front grille of the vehicle for optimal thermal and energy management. Conventionally shutters were controlled by reactive algorithm - that actuate based on reaction to powertrain cooling system response like engine coolant temperature. The predictive algorithm of aero shutter proactively actuates engine cooling fans and shutter to different positions to meet real time cooling requirement. This algorithm needs map of shutter position required for a given air flow requirement which is function of vehicle speed, fan speed, opening of another shutter (if dual shutters are used on two grilles). Deriving such map requires enormous number of simulations or wind tunnel tests at each of these parameter combinations. This paper presents Design of Experiments (DOE) studies using statistical approach to have minimal number of runs to develop such map.
2011-04-12
Technical Paper
2011-01-0523
William Nicholas Dawes, William Kellar PhD, Simon Harvey PhD, Neil Eccles PhD
Successful product development, especially in motorsport, increasingly depends not just on the ability to simulate aero-thermal behavior of complex geometrical configurations, but also the ability to automate these simulations within a workflow and perform as many simulations as possible within constrained time frames. The core of these aero-thermal simulations - and usually the main bottleneck - is generating the computational mesh. This paper describes recent work aimed at developing a mesh generator which can reliably produce meshes for geometries of essentially arbitrary complexity in an automated manner and fast enough to keep up with the pace of an engineering development program. Our goal is to be able to script the mesh generation within an automated workflow - and forget it.
2004-07-19
Technical Paper
2004-01-2469
MariaCristina Tosi, Luca Tentoni, Antoine Joulot, Jose' Antonio, Romera Perez
The Automated Transfer Vehicle (ATV) Thermal Control System (TCS) has the task to ensure the required internal environment at level of pressurized module and to thermally control the not pressurised modules and installed equipment, using passive and active control means, in response to the relevant applicable requirements. The ATV vehicle is assially subdivided into three main modules: the Integrated Cargo Carrier (ICC), the Equipped Avionics Bay (EAB) and the Equipped Propulsion Bay (EPB). Each of these modules present elaborated and specific thermal design solutions, to satisfy the different required operative tasks. The extensive thermal analysis campaign performed at ATV vehicle level and in progress for the next Qualification Review (QR) to justify and support the thermal control design solutions and verification status is described.
2004-07-19
Technical Paper
2004-01-2438
H. Y. (Jannivine) Yeh, Cheryl B. Brown, Frank F. Jeng, Chin H. Lin, Michael K. Ewert
The development of the Advanced Life Support (ALS) Sizing Analysis Tool (ALSSAT) using Microsoft® Excel was initiated by the Crew and Thermal Systems Division (CTSD) of Johnson Space Center (JSC) in 1997 to support the ALS and Exploration Offices in Environmental Control and Life Support System (ECLSS) design and studies. It aids the user in performing detailed sizing of the ECLSS for different combinations of the ALS regenerative system technologies (1, 2). This analysis tool will assist the user in performing ECLSS preliminary design and trade studies as well as system optimization efficiently and economically.
2004-07-19
Technical Paper
2004-01-2425
Gaetana Bufano, Elena Brach Prever, Valter Perotto, Paolo Vaccaneo, Zoltan Szigetvari, Jan Persson, Johannes Witt
The Columbus ECS PFM Test was intended as the final verification of the Module Thermal Design after a series of successful tests at subsystems level (e.g. the Active Thermal Control Subsystem and the Environmental Control and Life Support System) The test campaign has been articulated as a sequence of several test cases to investigate the main thermal aspects, to prove the Module thermal design in the extreme operative conditions and to correlate the thermal mathematical model (TMM). The interpretation of test results and the correlation confirmed that the thermal design of the module is adequate, but some areas of concern remain, mainly for the difficulty to translate to 0-g the results of a complex test in 1-g environment, and for some aspects of the air and cabin loops.
2004-07-19
Technical Paper
2004-01-2430
Jon B. Holladay, Shawn E. Reagan, Greg Day
A newly developed solid-state temperature controller will offer greater flexibility in the thermal control of aerospace vehicle structures. A status of the hardware development along with its implementation on the Multi-Purpose Logistics Module will be provided. Numerous advantages of the device will also be discussed with regards to current and future flight vehicle implementations.
2004-07-19
Technical Paper
2004-01-2354
Kazutaka Miyatake, Kazumi Kobayashi, Yas Takashima, Masaaki Suzuki
The use of Superheated Steam (SHS) has been known for nearly 100 years. Utilization of SHS has been limited due to lack of technological development and knowledge about its potential application. SHS is achieved by heating the saturated steam to temperatures exceeding 100° C. This research was conducted to investigate the multipurpose applications of superheated steam particularly for cooking, which is an area lacking in technological developments. Even under normal or hypo baric conditions, high thermal energy from combined latent and superheat generated from a carbon-heating element controlled by varying electromagnetic induction. Multiple applications includes instrument sterilization, sterilization and deodorization of air, material recovery, removal of contaminants, induction of chemical reactions and cooking.
2004-07-19
Technical Paper
2004-01-2365
John A. Hogan, Julie A. Levri, Rich Morrow, Jim Cavazzoni, Luis F. Rodriguez, Rebecca Riaño, Dawn R. Whitaker
An ongoing effort is underway at NASA Ames Research Center (ARC) to develop an On-line Project Information System (OPIS) for the Advanced Life Support (ALS) Program. The objective of this three-year project is to develop, test, revise and deploy OPIS to enhance the quality of decision-making metrics and attainment of Program goals through improved knowledge sharing. OPIS will centrally locate detailed project information solicited from investigators on an annual basis and make it readily accessible by the ALS Community via a Web-accessible interface. The data will be stored in an object-oriented relational database (created in MySQL®) located on a secure server at NASA ARC. OPIS will simultaneously serve several functions, including being an research and technology development (R&TD) status information hub that can potentially serve as the primary annual reporting mechanism for ALS-funded projects.
2004-07-19
Technical Paper
2004-01-2359
F. Michard, C. Combes, E. Fournier, E. Werling
In the short term, traditional thermal control techniques, currently reaching their potential limit, will no longer meet the challenge imposed by the natural evolution in electronic packaging, characterized by an ever-increasing level of integration and power. In this context, new architectures must be developed, with thermal control based on high performance heat transfer devices. The Integration of Miniature Heat Pipe (MHP) seems to be one of the most effective and promising solutions for the future. This paper summarizes the work, performed within the frame of a partnership with the CNES, aiming at contributing to develop and evaluate this technology. Beyond theoretical and technological studies, we have manufactured or supplied several miniature heat pipe devices (MHPD) to constitute the elementary thermal control blocks, corresponding to the main packaging hierarchical levels (components, boards, equipment) of future generation of space vocation electronic units.
2004-07-19
Technical Paper
2004-01-2309
R. V. Gavrylov, Yu. A. Melenevskiy, V. I. Dranovskiy, M. I. Koshkin
The stand rig facility for thermo-vacuum testing of Space vehicles (STVT), described in this paper, is intended for simulation of: space vacuum, cold Space environment, electromagnetic radiation by the Sun and Earth, and Earth-albedo, as well as determination of influence of these factors on thermal regime of hardware and instruments of SV.
2004-07-19
Technical Paper
2004-01-2307
Pierre Jamotton, Antonio Cucchiaro, Isabelle Domken
Both Planck and Herschel satellite are cryogenic payloads, the first one having a cold point around 0.1 [K], the second one around 0.3 [K]. Not only the detectors are cooled, but also major subsystems and systems of the spacecraft’s. The Centre Spatial de Liège (CSL) is involved in the testing of several parts of the spacecraft’s, starting from optical tests on the mirrors or on the telescopes, going on with cryogenic vibration testing of scientific focal plane instruments, ending with the full Planck spacecraft testing. Each test requires temperature lower than 20 [K], in volumes ranging from 1 [m3] to 60 [m3], cooling down several kilograms to more than one ton, and withstanding heat load up to 150 [W] in stabilization. These tests are done is 4 different facilities of CSL, linked to a common cold Helium network. This latter allows full flexibility for operation of the different facilities quasi independently.
2004-07-19
Technical Paper
2004-01-2310
M. T. Pauken, G. M. Kinsella, K. S. Novak, G. T. Tsuyuki, C. J. Phillips
In January 2004, two Mars Exploration Rovers (MER) landed on the surface of Mars to begin their mission as robotic geologists. A year prior to these historic landings, both rovers and the spacecraft that delivered them to Mars, were completing a series of environmental tests in facilities at the Jet Propulsion Laboratory. This paper describes the test program undertaken to validate the thermal design and verify the workmanship integrity of both rovers and the spacecraft. The spacecraft, which contained the rover within the aeroshell, were tested in a 7.5 m diameter thermal vacuum chamber. Thermal balance was performed for the near earth (hot case) condition and for the near Mars (cold case) condition. A solar simulator was used to provide the solar boundary condition on the solar array. IR lamps were used to simulate the solar heat load on the aeroshell for the off-sun attitudes experienced by the spacecraft during its cruise to Mars.
2004-07-19
Technical Paper
2004-01-2274
Vincenzo Mareschi, Valter Perotto, Matteo Gorlani, Danilo Lazzeri, Olivier Pin
Stochastic method is being used in several domains for design optimisation, but its application to spacecraft thermal control design is not yet consolidated. The paper presents an assessment of this technique applied to spacecraft thermal control design, made by Blue Engineering and Alenia Spazio under ESA contract, with the objective to assess the applicability of the method, the requirements for its implementation, the effects on the design process.
2004-07-19
Technical Paper
2004-01-2273
D. Martin
Traditionally, the preliminary thermal design is behind the mechanical and electrical spacecraft design. Many factors contribute to this including a lack of detailed physical characteristics of the spacecraft and knowledge of the distribution of the thermal loads within the spacecraft. Therefore, the thermal design typically reacts to the mechanical and electrical designs. The thermal analyst gets a configuration and then tries to wrap an acceptable solution around it. The analyst relies on years of experience and trial and error to determine the appropriate design cases and create a thermal design. Depending on the experience level of the engineer, several iterations may be necessary to determine the worst-case design points and an acceptable thermal design.
2004-07-19
Technical Paper
2004-01-2276
R. V. Gavrilov, V. N. Fenchenko, A. M. Kislov, V. G. Romanenko
The software package for computerized modeling of thermal regimes of a spacecraft (S/C) provided with passive and active means of temperature control, under conditions of orbital flight mission and at thermo-vacuum testing conditions, is represented. The programs of the package have been developed in Object Pascal programming language. Description of the package programs and their basic functions is outlined. An example of calculations for thermal regimes of satellite, with its longitudinal axis oriented on the Sun, is represented.
2004-07-19
Technical Paper
2004-01-2306
A. Robson, S. Dolce, P. Ayache
MetOp is a series of three meteorology and climate monitoring satellites, which will be launched using the Russian Soyuz-Fregat vehicle over a period of 14 years starting in 2005. MetOp will form part of the American ‘Polar Orbiting Environmental Satellites’ (POES) programme, a further step in European/American collaboration in space. The MetOp satellites will fly in a sun-synchronous polar orbit at an altitude of between 800 and 850km, with a repeat cycle of 29 days. The satellite is based on the successful Spot platform, which has carried a number of European earth observation satellites over the last 15 years, and consists of two parts: 1. The Payload Module (or PLM) which carries twelve instruments, provided by the European Space Agency (ESA), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), the American National Oceanic and Atmospheric Administration (NOAA) and the French space agency, CNES. 2.
2004-07-19
Technical Paper
2004-01-2305
Juergen Schilke, Silvio Dolce, Elena Checa, Gaetan Piret
The METOP satellite is Europe’s polar-orbiting meteorological satellite. It balances the US provided POES (Polar Orbiting Environmental Satellite) program. 3 flight models are built under EUMETSAT/ESA contract by an industrial consortium led by Astrium. Instruments are supplied by NOAA and EUMETSAT. This paper gives a summary on the thermal testing of METOP payload module. The testing started with TB test on EM, conducted in may 2001 at ESTEC Large Space Simulator. It was followed by a TV test on the same model in June 2001. The test was split into a TB part with solar simulation and a TV part without. Between both tests a test jig carrying a set of stimuli and test equipment was installed on the PLM. In November 2002 the PLM flight model 1 was subjected to a TV test at ESTEC with additional TB phases to improve the TMM. In February 2004 PLM flight model 2 has executed also TV testing at ESTEC.
2004-07-19
Technical Paper
2004-01-2304
Christian Vettore, Federico Pamio, A. A. Sochivko, I. P. Lukaschuk, A. S. Smoljaninov
This paper describes the Thermal Balance test that has been performed on the PAMELA telescope Pressurized Container (PC) to verify the performance of the PC Thermal Control System (TCS). The PC will be attached outside the Russian satellite RESOURS DK to be flown in2004 The thermal control system of the PAMELA PC is based on a mechanical pumped loop fed with Isooctane as working fluid. The test has been performed with PAMELA Structural Thermal Model (STM) inside the PC to have representative interfaces for the thermal control system. Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber by means of a complex system of IR lamps suitably oriented toward the PC and mechanically mounted on a tubular structure outside the PC. Overall test results have been excellent; PAMELA thermal control system thermal/fluidic requested performance have been verified. PAMELA telescope thermal interfaces have been confirmed as well.
2011-10-04
Technical Paper
2011-36-0129
Luiz Carlos Sandoval Góes, Eduardo Augusto Gallo
It was purposed in this study the use of thermal comfort index as feedback parameter for multivariable control of aeronautical air conditioned system. Simulating the developed thermal model, the efficiency gain by using this control law was observed by comparing it with standard control models.
2011-06-13
Technical Paper
2011-38-0034
Michael Papadakis, Alonso O. Zamora Rodriguez, Rodrigo Hoffmann Domingos
Results from a two-dimensional computer model developed at Wichita State University (WSU) for bleed air system analysis are compared with experimental data from icing tunnel tests performed with a wing model equipped with a hot air ice protection system. The computer model combines a commercial Navier-Stokes flow solver with a steady-state thermodynamic analysis model that applies internal flow heat transfer correlations to compute wing leading edge skin temperatures and the location and extent of the runback ice. The icing tunnel data used in the validation of the computer model were obtained at the NASA Icing Research Tunnel using representative in-flight icing conditions and a range of bleed air system mass flows and hot air temperatures. Correlation between experiment and analysis was good for most of the test cases used to assess the performance of the simulation model.
2004-07-19
Technical Paper
2004-01-2391
Michele Cairola, Roberto Passini, Federica Tessarin, Ludovic Ouchet, Claudio Damasio
ESA has planned two important missions for performing astronomical investigations in the infrared and sub-millimetre wavelength range: Herschel satellite has an observatory type mission and is the fourth cornerstone mission (CS4) of the “Horizon 2000” programme. It will carry three instruments (HIFI, SPIRE, and PACS) for high and medium resolution spectroscopy, imaging and photometry over the sub-millimetre and far-infrared range. A 3.5 m telescope will focus the incoming radiation on the Focal Plane Units of these instruments. Planck satellite has a survey type mission and is the third Medium mission (M3) of the “Horizon 2000” programme. It will provide a definitive high-angular resolution map of the cosmic microwave background anisotropies over at least 95% of the sky and over a wide frequency range. A 1.5 m telescope will focus the incoming radiation on the focal plane shared by the two instruments (LFI and HFI).
2004-07-19
Technical Paper
2004-01-2569
Atindra K. Mitra, Keith W. Jones
An architecture for thermal management of avionics and electronics systems based on integrated electronics and thermal design at the PCB board level is introduced. Advantages of this approach include the reduction of the number of external components that are required in relation to existing approaches to advanced liquid-based thermal management techniques along with other gains in efficiency due to the PCB board-level adaptivity that is embedded in this design solution. In addition, this type of system can potentially be implemented as a sealed self-contained solution that will allow maintenance personnel to avoid dealing to hazardous cooling compounds as part of the system maintenance procedures.
2004-07-19
Technical Paper
2004-01-2568
A. Hauser, J. Hinger, K. Wagner
Herschel is an ESA scientific satellite with a cryogenic payload for astronomical infrared observations, to be launched in 2007. The thermal control system of the Herschel Extended Payload Module (EPLM) shall provide a 1.65 K heat sink for 3.5 years mission lifetime. The major parts of the EPLM are the Cryostat Vacuum Vessel (CVV), the Herschel Solar Array and Sunshade (HSS) and the 3.5 m Telescope. The CVV contains a 2367 ❘ superfluid Helium tank and the Optical Bench, which carries the three scientific instruments. The CVV also carries the Telescope and the Local Oscillator Unit (LOU) used for one scientific instrument. Furthermore, the CVV is equipped with external radiators and internal vapour-cooled shields. The EPLM is mounted on top of the Herschel Service Module (SVM). In addition, a thermal shield is arranged between SVM and CVV. This paper describes the EPLM thermal design and the main thermal analysis results for operation on ground and in orbit.
2004-07-19
Technical Paper
2004-01-2570
Scott Newland, Roland Watts
Abstract High thermal conductivity composite heat sinks for various advanced fighter and helicopter avionics applications have been designed, fabricated, and tested. Baselines are existing VME and SME architecture module aluminum and AlBeMet heat sink thermal planes for avionic boxes. Novel manufacturing approaches combined with pitched-based graphite fiber materials and non-destructive thermal validation methodologies led to delivery of hardware to prime systems contractors for qualification. The composite heatsink has a definite advantage in price, weight, stiffness, performance and manufacturing (1).
2004-07-19
Technical Paper
2004-01-2573
Randy Ashford
The F/A-22 Raptor Environmental Control System/Thermal Management System (ECS/TMS) software is a real-time digital control system application. The system is comprised of 4 separate computer software configuration items (CSCI). Verification & Validation (V& V) activities of such a system is complex and performed in stages. The process begins with structured design and analysis techniqes and culminates with actual flight test. This paper provides an overview of the V& V effort to perform the formal software qualification testing to flight certify this software. First, an overview of the system and software architecture is provided. Then each level of testing is described. Development and problem report metrics are shown. Finally, lessons learned are presented.
2004-07-19
Technical Paper
2004-01-2572
Jeffry Ramsey, Keith W. Jones, Atindra K. Mitra
The bipolar junction transistor (BJT) generates heat that can lead to thermal runaway. BJT temperature increases can affect how well this device performs. Moreover, integrated circuits (IC) consisting of large numbers of BJTs can have an adverse effect on how the device performs in aggregate. This paper discusses the BJT functionality and causes of heat generation and proposes potential solutions to this thermal problem.
2004-07-19
Technical Paper
2004-01-2556
J. van Es, G. van Donk, A. Pauw, C.A.M. Rens, J. Jaarsma, M.P.A.M. Brouwer, B. Verlaat
The AMS Tracker Thermal Control System (TTCS) is a two-phase cooling system developed by NIKHEF (The Netherlands), Geneva University (Suisse), INFN Perugia (Italy), Sun Yat Sen University Guangzhou (China) and NLR (The Netherlands). The TTCS is a mechanically pumped two-phase carbon dioxide cooling loop. Main objective is to provide accurate temperature control of AMS Tracker front-end electronics. Additional objective is to prove and qualify a two-phase pumped cooling in orbit and collect operational data in μ-g environment over a period of three years. The paper describes the concept selection, breadboard results and an outlook to the experiments in orbit.
2004-07-19
Technical Paper
2004-01-2558
E. Grob, C. Baker, T. McCarthy
Goddard Space Flight Center’s Geoscience Laser Altimeter System (GLAS) is the sole scientific instrument on the Ice, Cloud and land Elevation Satellite (ICESat) that was launched on January 12, 2003 from Vandenberg AFB. A thermal control architecture based on propylene Loop Heat Pipe technology was developed to provide selectable/stable temperature control for the lasers and other electronics over the widely varying mission environment. Following a nominal LHP and instrument start-up, the mission was interrupted with the failure of the first laser after only 36 days of operation. During the 5-month failure investigation, the two GLAS LHPs and the electronics operated nominally, using heaters as a substitute for the laser heat load. Just prior to resuming the mission, following a seasonal spacecraft yaw maneuver, one of the LHPs deprimed and created a thermal runaway condition that resulted in an emergency shutdown of the GLAS instrument.
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