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MOL The Mission Operations Laboratory MOL The Mission Operations Laboratory NASA MSFC Engineering Directorate Huntsville, Alabama Delta Training Strategy Team (TST) May 29, 2012 Coarsening in Solid-Liquid Mixtures 2 (CSLM-2) Glenn A. Ferraro EO20 256-961-02334 glenn.a.ferraro@nasa.gov
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MOL The Mission Operations Laboratory Page 2 NASA MSFC Engineering Directorate Huntsville, Alabama Objective The TST is a structured planning and decision-making group who determines the payload training requirements for each payload or complement of payloads or experiments. Payload training requirements, and what will be needed to fulfill those requirements for crewmembers, are discussed, defined, and agreed upon during this process.
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MOL The Mission Operations Laboratory Page 3 NASA MSFC Engineering Directorate Huntsville, Alabama Agenda CSLM-2 Overview CSLM-2 Hardware Description CSLM-2 Operations CSLM-2 Operations Flow Chart CSLM-2 Crew Training Inc 33/34 Training Development Milestones
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MOL The Mission Operations Laboratory Page 4 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Overview Science Objectives The experiment will examine how dendrites form during solidification into an under cooled melt. These dendrites possess secondary and sometimes even ternary arms. While the tip radius and tip velocity of the dendrite are set by the growth conditions, the side branches behind the tip undergo a coarsening process under nearly isothermal conditions. This coarsening process sets the final arm thicknesses and distances between dendrite arms in the solidified structure, almost independent of the length-scale given by the dendrite tip. Since there is a close relationship between the size scale of the coarsened dendritic structure and the mechanical properties of the material, a greater understanding of this process will have important practical implications. Purpose The objective is to study coarsening in solid-liquid mixtures at low volume fractions of solid. The topology and morphology of these dendritic mixtures will be determined using three-dimensional reconstructions and phase field simulations that employ these reconstructions as initial conditions will provide insights into the mechanisms of coarsening. These low volume fractions will enable the PD/PI team to examine coarsening of single or a few dendrites, something that is impossible on the ground. These studies will provide insights into the dynamics of morphological evolution of these systems and will point the way to the formulation of models of this technologically important coarsening process. Coarsening Is a process in which particle-matrix interfacial area in a two-phase system decreases with time, thus reducing the energy of the system. Small particles dissolve and transport their mass by material diffusion due to a concentration gradient in the particle-matrix interface. Concentration depends upon particle curvature. Particles which are smaller than the average size have a concentration at the interface which is higher than that in the matrix, while particles which are larger have a lower concentration at the interface. Thus the large particles tend to grow at the expense of the small particles, the average particle size increases, and the total number of particles decreases with time.
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MOL The Mission Operations Laboratory Page 5 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Hardware Electronics Control Unit (ECU) The Electronics Control Unit (ECU) contains both the Power Distribution System and the Data Acquisition and Control System. ECU software controls each experiment through a series of operating states. During these states, the status of selected parameters is displayed on an LCD screen. Crew procedures will periodically direct crew members to check LCD displays to verify humidity and other experiment parameters. Power Two lever-lock toggle switches control experiment power and activate the experiment. A third lever-lock toggle switch controls experiment modes in the event of off-nominal conditions requiring the manual quench of the sample holder. Temperature Control The primary function of the ECU is to control the heating of the lead-tin samples in the Sample Chamber. The ECU monitors and records sample temperatures. Software performs closed-loop control of the heater power based upon the sample temperature. Following the heat/soak cycle, the ECU software initiates the Quench mode. Data The ECU contains a hard drive that records data during the experiment run. This data is transferred to the MSG Laptop Computer following the experiment run and is eventually downlinked to the ground.
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MOL The Mission Operations Laboratory Page 6 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Hardware (cont.) Sample Processing Unit (SPU) The Sample Processing Unit (SPU) houses the chamber where the lead-tin samples are contained and provides the Vacuum, Heating, and Quench systems needed for the experiment. The SPU is connected to the Electronics Control Unit (ECU) via an interconnect cable. After sample processing is complete, the SPU is removed and replaced by another SPU. Key components include the following: Sample Chamber Large cylinder housing experiment samples. The Sample Chamber is evacuated prior to each experiment run. Following processing, it is returned to stowage. SPU Comm Port Provides SPU identification to the ECU and receives solenoid valve power and control from the ECU. Water Reservoir Contains the cooling water used to quench the samples at the end of sample processing. When water quench is required, a solenoid valve automatically opens, allowing air to pressurize the water in the reservoir. The burst disc in the reservoir opens and allows water flow into the spray nozzles and onto the Sample. Air Cylinder When activated by experiment software, the Air Cylinder provides the pressure required to force water into the Sample Chamber for quenching. Pressure Gauge Indicates pressure inside air cylinder
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MOL The Mission Operations Laboratory Page 7 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Hardware (cont.) Base Plate The plate between CSLM-2 experiment hardware and MSG Work Volume Floor. Both the ECU and SPU mount to this 33 cm x 31.2 cm plate Cables Provide the power and data interface between CSLM-2 hardware and MSG. ECU Power and ECU Data connects between the ECU and the back of the MSG Work Volume. ECU Comm connects between the ECU and the SPU.
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MOL The Mission Operations Laboratory Page 8 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Hardware (cont.) Vacuum Hose Vacuum hose is used to evacuate the sample chamber via ISS VES prior to SPU processing. Downlink Adapter Shorting Cap Backshell used to modify a specific SPUs processing parameters When connected to ECU J750, it triggers ground support mode in the ECU and allows for the transfer of files from the MLC into the ECU.
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MOL The Mission Operations Laboratory Page 9 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Operations Operations The four main phases in CSLM-2 Operations are: Setup, Vacuum Draws, Sample Processing, and Stow. During the setup phase, the hardware is installed and configured and a VES leak test is performed. Next, the Vacuum Draws are performed to prepare the sample chamber. Four Vacuum Draws are performed in each Vacuum Draw Sequence, each lasting 8, 16, 6, and 23 hours, respectively. A Vacuum Draw sequence is schedule prior to Sample Processing. Upon conclusion of each Vacuum Draw Sequence the samples are processed. At the end of the experiment, all hardware is stowed.
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MOL The Mission Operations Laboratory Page 10 NASA MSFC Engineering Directorate Huntsville, Alabama CSLM-2 Operations Flowchart 1.ACTIVATE MSG AND LOAD SW 2.CONFIGURE MSG 3.INSTALL CSLM-2 ECU AND SPU 4.ACTIVATE CSLM-2 5.SECURE WV AND POWER DOWN MSG FACILITY 1.INITIATE SAMPLE HEATING 2.UNATTENDED DELAY 3.UNATTENDED SAMPLE PROCESSING 4.DATA TRANSFER 5.VERIFY TRANSFER AND EXCHANNGE SPU 6. UNATTENDED DOWNLINK 1.CONFIGURE MSG FACILITY 2.CHECK HUMIDIY LEVELS 3.OPEN VENT AND VACUUM VALVES 4.UNATTENDED VACUUM DRAWS (1-4) 5.TERMINATE VACUUM DRAW 6.PREP FOR NEXT DRAW (OR SAMPLE PROCESSING IF DRAWS ARE COMPLETE) 1.POWER DOWN MSG FACILITY 2.DISCONNECT CSLM-2 ECU 3.STOW ALL CSLM-2 HARDWARE 1. SETUP 2. VACUUM DRAWS (1-4) 3. SAMPLE PROCESSING 4. STOW CONTINUE UNTIL LAST SPU PROCSSED
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MOL The Mission Operations Laboratory Page 11 NASA MSFC Engineering Directorate Huntsville, Alabama Crew Training Current Training Plan 1 hour Instructor Lead Ground Training provided at JSC SSTF, CSLM-2 Hardware is setup in the MSG Training Unit. Proposed Training Plan for Inc 33/34 No ground training. Training will be conducted via OBT. Training will be conducted via on board video training.
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MOL The Mission Operations Laboratory Page 12 NASA MSFC Engineering Directorate Huntsville, Alabama Inc 33/34 Training Development Milestones Courseware DeliverySept. 2012 PTDROct. 2012 Dataset Baseline – Curriculum/HoursOct. 2012 Ready for TrainingDec. 2012
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