From: Microgravity Research Program Office
Posted: Wednesday, February 27, 2002
Physical Sciences Division
Weekly Highlights for Week Ending 2/20/2002
*** Indicates item is appropriate for the HQ senior staff and may appear on the OBPR Web site: http://spaceresearch.nasa.gov
CURRENT AND FORMER MICROGRAVITY COMBUSTION INVESTIGATORS BECOME NEW MEMBERS OF NATIONAL ACADEMY OF ENGINEERING: The National Academy of Engineering has elected 74 members and seven foreign associates to its membership, NAE President Wm. A. Wulf announced. This brings the total U.S. membership to 1,857 active members and 250 members emeriti, and the number of foreign associates to 158.
Election to the National Academy of Engineering is one of the highest professional distinctions that can be accorded an engineer. Academy membership honors those who have made "important contributions to engineering theory and practice" and those who have demonstrated "unusual accomplishment in the pioneering of new and developing fields of technology." A list of the newly elected members and foreign associates follows, with their primary affiliations at the time of election and a brief statement of their principal engineering accomplishments.
Ronald K. Hanson, chair, department of mechanical engineering, Stanford University, Stanford, Calif. For the development and application of innovative laser diagnostics and sensors in the fields of combustion, chemical kinetics, and power conversion.
James C. Keck, Ford Professor of Engineering Emeritus and senior lecturer, Massachusetts Institute of Technology, Cambridge. For developing innovative, widely used new concepts for modeling coupled chemical and physical phenomena in engine combustion and high-temperature flows.
Chung K. (Ed) Law, Robert H. Goddard Professor, department of aerospace and Mechanical engineering, Princeton University, Princeton, N.J. For outstanding contributions to the understanding of the fundamentals of combustion processes and theory and the applications in propulsion systems.
William A. Sirignano, professor of mechanical and aerospace engineering, University of California, Irvine. For contributions to the science and technology of spray combustion systems for propulsion.
NAE New Foreign Associates
Norbert Peters, Center for Turbulence Research, Stanford University, Stanford, Calif. For contributions to the field of combustion modeling of turbulent flames and the development of chemical kinetic mechanisms for hydrocarbon oxidation.
EDUCATION and OUTREACH
EDUCATIONAL OUTREACH: As part of National Engineers Week, John McQuillen (GRC) visited Jefferson Area Jr./Sr. High School in Jefferson, Ohio. John talked about engineering as a career as well as presented various math and science concepts involved in microgravity.
ISS FLIGHT PROGRAM
PHYSICS OF COLLOIDS IN SPACE ON ISS: During the 138 hours of run time this week, EXPPCS successfully initiated the aggregation of the fast fractal sample by performing an in situ combination of its colloid and salt solutions. The data clearly show the silica fractal network has formed and is continuing to evolve. We have observed a curious phenomenon this week. Since the transition to XPOP attitude on Sunday 2/17 (early in Day 049), low angle dynamic light scattering has been detecting a signal with approximately a 90 minute period. This appears to be due to small periodic temperature variations within the experiment possibly correlated with the ISS orbit. This has little impact on the science, but the science team is working to understand why this effect has not been seen in previous low angle dynamic measurements on other samples.
InSPACE FLIGHT HARDWARE TURNED OVER TO KSC: Members of the Investigating the Structure of Paramagnetic Aggregates of Colloidal Emulsions (InSPACE) Glovebox Investigation team supported several activities at KSC. Following successful Off-Line testing, InSPACE became the first science research payload to be integrated and tested with the flight MSG (On-Line testing was performed with SAMS one day prior to this activity). Increment 5 astronaut Peggy Whitson performed the hardware installation. InSPACE Project Scientist, Juan Agui (GRC) and Project Lead, Adabelle Narvaez-Legeza (GRC) together with several MSG and KSC personnel then performed a number of functional interface tests. While there were many delays and a few procedural deviations, testing was ultimately successful. This testing was performed via a temporary transfer of the hardware to KSC. The InSPACE hardware was transferred back Off-Line again so that a few outstanding items could be completed such as labeling and cleanliness. InSPACE hardware, with the exception of the Coil Assemblies, which are late stow were then turned over to KSC on 2/7/02.
MICROGRAVITY RESEARCH PROGRAM OFFICE (MRPO) PAYLOAD OPERATIONS STATUS ON THE INTERNATIONAL SPACE STATION (ISS) UF1 STAGE: Have successfully completed Week#10 (2/17-23/02) of Increment 4 UF1 Stage, and have entered into Week#11. All MRPO payloads have completed their scheduled operations and are looking forward to a busy week involving plant growth, crystal growth, cell preservation phase, and the study of colloids in space. On the morning of 2/26/02, the Physics of Colloids in Space (PCS) experiment (study of colloids) reported a possible failure with their data/Operating System hard drive and troubleshooting is now in progress to correct the problem.
MICROGRAVITY SCIENCE GLOVEBOX (MSG): The MSG Flight Unit Acceptance Review II was conducted at the Kennedy Space Center (KSC), 2/11-20/02. Acceptance of the Flight Unit by the European Space Agency (ESA) from ASTRIUM will occur after Action Items from the review have been completed. No items were identified from the review as a constraint for Multi-Purpose Logistics Module (MPLM) installation. A de-cable review was conducted on 2/20/02, concluding that MSG on-line testing has been successfully completed and the MSG Rack was ready for closeout activities. The MSG Rack is scheduled for MPLM installation on 2/27/02. Turnover of stowage items is ongoing in support of the Bench review, scheduled 3/5-6/02.
FLUIDS AND COMBUSTION FACILITY (FCF): The Fluids and Combustion Facility is a payload planned for the US Laboratory Module on the International Space Station. The assembly of the Engineering Model of the Combustion Integrated Rack is nearing completion, with the major milestone of integration of the combustion chamber and optics bench into the EM rack being accomplished. Testing of the gas delivery, flow, and exhaust systems were completed with success. The Passive Rack Isolation System being developed by Boeing was selected to provide the reduced acceleration environment for the CIR. The Active Rack Isolation System was deleted from the CIR design after considering the science requirements for the acceleration environment, the predicted performance of a passive isolation system, and the benefits to having a passive system rather than an active, electronically controlled system
DEVELOPMENT OF A NEUTRON SPECTROMETER TO ASSESS BIOLOGICAL RADIATION DAMAGE BEHIND SPACECRAFT MATERIALS: Principal Investigator, Dr. Richard H. Maurer of the Johns Hopkins University, has reported that a paper, entitled "High Energy Neutron Spectroscopy with Thick Silicon Detectors," has been submitted to the journal Radiation Research (Oakridge, TN). The results reported are a validation and verification of the methods used to infer high-energy neutron spectra (supplied by Los Alamos) from depositions in thick silicon detectors. This detector type is the basis of the high-energy channel to be used on a balloon flight instrument and originally proposed and accepted for the now cancelled Mars 03 Lander. The National Space Biomedical Research Institute (NSBRI) and NASA are co-sponsors.
IDENTIFICATION AND QUANTITATIVE MEASUREMENTS OF CHEMICAL SPECIES BY MASS SPECTROMETRY: The objective of this work is to develop and demonstrate a new microscale mass spectrometer system for chemical species measurements. The construction and evaluation of a prototype continues with some limits to the mass resolution being found that were not as good as predicted. Various causes were identified and improved. The resolution is still sufficient to perform gross respiration measurements that are now performed on the Space Station using the GASMAP system. The system is quite small: the mass spectrometer itself weighs only 153 gm. Also accomplished was the remote communication over a wireless modem and the Ethernet. The co-I successfully accessed an instrument located in St. Louis from his office in Santa Fe, NM.
MODELING RELAXATION AND JAMMING IN GRANULAR MEDIA: Fluid Physics PI Prof P. Schiffer (penn State), and Co-I A.-L. Baraba´si (Notre Dame) introduce a stochastic microscopic model to investigate the jamming and reorganization of grains induced by an object moving through a granular medium. The model reproduces the experimentally observed periodic sawtooth fluctuations in the jamming force and predicts the period and the power spectrum in terms of the controllable physical parameters. It also predicts that the avalanche sizes, defined as the number of displaced grains during a single advance of the object, follow a power law, where the exponent is independent of the physical parameters. This was reported in the following paper:
B. Kahng, I. Albert, P. Schiffer, and A.-L. Baraba´si " Modeling relaxation and jamming in granular media," PHYSICAL REVIEW E, VOLUME 64, 051303, 2001.
GRANULAR DRAG ON A DISCRETE OBJECT: SHAPE EFFECTS ON JAMMING: Fluid Physics PI Prof P. Schiffer (penn State), and Co-I A.-L. Baraba´si (Notre Dame) study the drag force on discrete objects with circular cross section moving slowly through a spherical granular medium. Variations in the geometry of the dragged object change the drag force only by a small fraction relative to shape effects in fluid drag. The drag force depends quadratically on the object's diameter as expected. They do observe, however, a deviation above the expected linear depth dependence, and the magnitude of the deviation is apparently controlled by geometrical factors. This was reported in the following paper:
I. Albert, J. G. Sample, A. J. Morss, S. Rajagopalan, A.-L. Baraba´si, and P. Schiffer "Granular drag on a discrete object: Shape effects on jamming," PHYSICAL REVIEW E, VOLUME 64, 061303, 2001.
MIT GROUP STIRS THE BEC: In a recent article in Physical Review Letters, Wolfgang Ketterle's group describes how they studied the nucleation of vortices in a Bose-Einstein condensate stirred by a laser beam. They were able to see the vortex cores by using time-of-flight absorption imaging. Either a discrete resonance or a broad response of the condensate was visible as the stir frequency was varied, depending on the size of the stirring beam. Because stirring beams small compared to the condensate size generated vortices below the critical rotation frequency for the nucleation of surface modes, a local mechanism of vortex generation is suggested. The group also observed centrifugal distortion of the condensate due to the rotating vortex lattice and found evidence for bent vortices.
The article "Vortex Nucleation in a Stirred Bose-Einstein Condensate" by C. Raman, J. R. Abo-Shaeer, J. M. Vogels, K. Xu, and W. Ketterle (Phys. Rev. Lett. 87, 210402 (2001)) is available at http://ojps.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRLTAO000087000021210402000001&idtype=cvips&gifs=yes
Additional meetings and symposia can be found at: http://microgravity.grc.nasa.gov/ugml/ugmltext.htm
The MRPO Program Calendar can be found at:
March 18-22, 2002, 2002 American Physical Society March Meeting, Indianapolis, IN
April 20-23, 2002, 2002 American Physical Society April Meeting, Albuquerque, NM
April 22-25 2002, 2002 Applied Computational Research Society Joint Meeting: Computational Micro And Nano Technology, International Conference on Computational Nano Science , Modeling & Simlation of Microsystems
San Juan Marriott Resort, San Juan, Puerto Rico
May 9-11, 2002, Fundamental Physics Investigator Workshop, laguna Cliffs Marriott Resort, Dana Point, CA
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