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The history of testing of compact tubular modules in flowing NaK loops is summarized. Test procedures, data handling, and instrument calibration are discussed. Also included is descriptive information of the test facilities, operational problems encountered, and some recommendations for testing.
Computer programming, data processing, and a correlation study that employed data collected in the first phase test were used to demonstrate that standard test procedures and equipment could be used to collect a significant number of transfer functions from tests of the Lunar Module test article LTA-11. The testing consisted of suspending the vehicle from the apex fittings of the outrigger trusses through a set of air springs to simulate the free-free state. Impulsive loadings were delivered, one at a time, at each of the landing gear's attachment points, in three mutually perpendicular directions; thus a total of 36 impulses were applied to the vehicle. Time histories of each pulse were recorded on magnetic tape along with 40 channels of strain gage response and 28 channels of accelerometer response. Since an automated data processing system was not available, oscillograph playbacks were made of all 2400 time histories as a check on the validity of the data taken. In addition, one channel of instrumentation was processed to determine its response to a set of forcing functions from a prior LTA-11 drop test. This prediction was compared with drop test results as a first measure of accuracy.
The feasibility of using the space shuttle to launch planetary and DoD entry flight experiments was examined. The results of the program are presented in two parts: (1) simulating outer planet environments during an earth entry test, the prediction of Jovian and earth radiative heating dominated environments, mission strategy, booster performance and entry vehicle design, and (2) the DoD entry test needs for the 1980's, the use of the space shuttle to meet these DoD test needs, modifications of test procedures as pertaining to the space shuttle, modifications to the space shuttle to accommodate DoD test missions and the unique capabilities of the space shuttle. The major findings of this program are summarized.
The aerodynamic flight test procedures and results for the Space Shuttle orbiter are presented. The aerodynamic characteristics used in testing were determined from flights STS-1 and through STS-4. Normal force and pitching moment were different than predicted, suggesting an unanticipated aerodynamic force acting upward on the end of the orbiter. However, lateral-directional aerodynamic characteristics were in good management with good predictions. The flight measured aerodynamics are repeatable and show good correlation with angle of attack and angle of sideslip.
The unique capabilities of the National Full-Scale Aerodynamics Complex (NFAC) for testing rotorcraft systems are described. The test facilities include the 40- by 80-Foot Wind Tunnel, the 80- by 120-Foot Wind Tunnel, and the Outdoor Aerodynamic Research Facility. The Ames 7- by 10-Foot Subsonic Wind Tunnel is also used in support of the rotor research programs conducted in the NFAC. Detailed descriptions of each of the facilities, with an emphasis on helicopter rotor test capability, are presented. The special purpose rotor test equipment used in conducting helicopter research is reviewed. Test rigs to operate full-scale helicopter main rotors, helicopter tail rotors, and tilting prop-rotors are available, as well as full-scale and small-scale rotor systems for use in various research programs. The test procedures used in conducting rotor experiments are discussed together with representative data obtained from previous test programs. Specific examples are given for rotor performance, loads, acoustics, system interactions, dynamic and aeroelastic stability, and advanced technology and prototype demonstration models.
Three read/write random access memories, AM91L24, HM1-6514, and MWS 5114, were subjected to total dose irradiation at three dose rates, with electrical testing after each increment of dosage. Annealing measurements were performed after the radiation tests were completed. The AM91L24 showed a strong dose rate effect and substantial post-irradiation annealing of radiation-induced damage. The dose rate effect was that a lower dose rate produced less net damage than an eqivalent total dose applied at a higher rate. The HM1-6514 showed essentially no dose rate effect and no annealing damage, and the MWS 5114 exhibited a moderate effect with some annealing. It was concluded that dose rate is an important parameter in radiation test procedures for MOS microcircuits and that annealing measurements may be important evaluation aids for such tests.
The work accomplished in the summer of 1989 in association with the NASA/ASEE Summer Faculty Research Fellowship Program at Marshall Space Flight Center is summarized. The task involved study of the Orbital Maneuvering Vehicle (OMV) Video Compression Scheme. This included such activities as reviewing the expected scenes to be compressed by the flight vehicle, learning the error characteristics of the communication channel, monitoring the CLASS tests, and assisting in development of test procedures and interface hardware for the bit error rate lab being developed at MSFC to test the VCU/VRU. Numerous comments and suggestions were made during the course of the fellowship period regarding the design and testing of the OMV Video System. Unfortunately from a technical point of view, the program appears at this point in time to be trouble from an expense prospective and is in fact in danger of being scaled back, if not cancelled altogether. This makes technical improvements prohibitive and cost-reduction measures necessary. Fortunately some cost-reduction possibilities and some significant technical improvements that should cost very little were identified.
Two 22-cells 19Ah Nickel-Hydrogen (Ni-H2) Single Pressure Vessel (SPV) Qual batteries, one each from EPI/Joplin and EPI/Butler, were designed and procured. The two batteries differ in the cell encapsulation technology, stack preload, and activation procedure. Both the Butler and Joplin batteries met the specified requirements when subjected to qualification testing and completed 2100 and 1300 LEO cycles respectively, with nominal performance. This paper discusses advantages, design features, testing procedures, and results of the two single pressure vessel Ni-H2 batteries.
This is the Performance Verification Report, METSAT (S/N: 107) AMSU-A1 Receiver Assemblies, P/N 1356429-1, SIN: F04, P/N 1356409- 1, S/N: F04, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The AMSU-A receiver subsystem comprises two separated receiver assemblies; AMSU-A1 and AMSU-A2 (P/N 1356441-1). The AMSU-A1 receiver contains 13 channels and the AMSU-A2 receiver 2 channels. The AMSU-A receiver assembly is further divided into two parts; AMSU-A I - I (P/N 13 5 6429- 1) and AMSU-A 1 -2 (P/N 1356409-1), which contain 9 and 4 channels, respectively. The AMSU-A receiver subsystem is located in between the antenna and signal processing subsystems of the AMSU-A instrument and comprises the RF and IF components from isolators to attenuators. It receives the RF signals from the antenna subsystem, down-converts the RF signals to IF signals, amplifies and defines the IF signals to proper power level and frequency bandwidth as specified for each channel, and inputs the IF signals to the signal processing subsystem. The test reports for the METSAT AMSU-A receiver subsystem are prepared separately for Al and A2 receivers so that each receiver stands alone during integration of instruments into the spacecraft. This test report presents the test data of the N4ETSAT AMSU-A1 Flight Model No. 4 (FM-4) receiver subsystem. The tests are performed per the Acceptance Test Procedure (ATP) for the AMSU-A Receiver Subsystem, AE-26002/6A. The functional performance tests are conducted either at the component or subsystem level. While the component-level tests are performed over the entire operating temperature range predicted by thermal analysis, most subsystem-level tests are conducted at ambient temperature only. Key performances (bandpass characteristics and noise figure) of the receiver subsystem are verified over the operating temperature.
The Spaceport Command and Control System (SCCS) is the National Aeronautics and Space Administration's (NASA) launch control system for the Orion capsule and Space Launch System, the next generation manned rocket currently in development. This large system requires a large amount of intensive testing that will properly measure the capabilities of the system. Automating the test procedures would save the project money from human labor costs, as well as making the testing process more efficient. Therefore, the Exploration Systems Division (formerly the Electrical Engineering Division) at Kennedy Space Center (KSC) has recruited interns for the past two years to work alongside full-time engineers to develop these automated tests, as well as innovate upon the current automation process.
The off-gassing of ammonia from hardware and metabolic sources presents a unique challenge to trace contaminant control system design, driving process flowrates to meet crewed air quality requirements. Accurately simulating representative trace contaminant cabin loads during ground testing is necessary to validate component design as well as understand potential contaminant propagation across life-support system process interface boundaries. This effort is complicated by the observed temporal concentration instability of gaseous ammonia in ground test chambers. To this end, ammonia concentration decay rates were characterized under controlled environmental conditions to better understand underlying phenomena and quantify incidental mass losses. The suspected chemical interaction between ammonia and trace acetaldehyde was investigated and its effect on species quantification was examined by both gas chromatography-mass spectrometry and Fourier-transform infrared spectroscopy. Recommendations for ground test procedures were made in order to best compensate for undesirable ammonia mass losses and mitigate test artifacts.
The development of intumescent technologies to be used as both an excellent means of fire protection and resiliency and as a radioactive fixative, would most definitely benefit the safety of the general public and also the environment. The remediation and safe disposal of radioactive waste is of great important to both national security and the public health, as we carry the responsibility to not develop new ways of mitigating these hazards but also to lay the groundwork for future generations. The overall goal of this research is to enhance the fire resiliency and protection of fixatives and nuclear facilities in support of D and D activities. Specific objectives include: 1) identify and evaluate commercial-off-the-shelf (COTS) intumescent technologies, 2) conduct baseline fire testing of intumescent technologies, 3) develop a set of international standards to meet operational and safety requirements for D and D Technologies. In order to evaluate the above proposed research objectives, the following hypotheses have been postulated. - Select, test, and evaluate the suitability of certain 'near fit' ASTM flammability standards. - Baseline and down-select a set of existing COTS intumescent technologies (coatings and foams) to support D and D problem sets. - Determine feasibility of application methods for use inside a radioactive glovebox and hot cells for D and D purposes. - Develop international testing protocols for adapting the use of intumescent technologies to address needs of the D and D process. The proposed research will primarily take place at FIU-ARC. ARC and SRNL have conducted extensive coordination with the Savannah River Site's (SRS) 235-F PuFF facility personnel to facilitate planning in order to expedite the research and development (R and D) related to this effort. An initial set of documents associated with the specific facility hot cells, including schematics, assessment of the manipulator arms, anticipated particulate sizes of the Pu-238 contamination, an approved tooling list, etc., were formally reviewed and approved for release by the site to ARC. Utilizing these as a foundation, pre-planning for further adaptation of the intumescent technologies and the application during a full-scale cold demo at a hot cell testbed at ARC. One of the primary objectives is the testing and evaluation of the resistance of radiological shielding foams to thermal stressors. This objective was accomplished by conducting a flammability test and incremental temperature test. The goal of the flammability test is to conduct analytical tests to provide a classification for the foams as outlined below in accordance with IEC 60695-11-10. This test method is uniformly accepted throughout the industry as being critical indicators that quantifiably establish the flammability characteristics of plastics. It should be noted that polyurethane is not classified as a plastic, however, they do share similar properties deeming this a near fit test. IEC 60695-11-10:2013 specifies small-scale laboratory test procedures intended to compare the burning behavior of different materials when vertically or horizontally oriented test bar specimens are exposed to a small flame ignition source. Two test methods are described. Method A is a horizontal burning test and is intended to determine the linear burning rate of materials under specific test conditions. Method B is a vertical burning test and is intended to determine whether materials self-extinguish under specific test conditions. The purpose of the incremental temperature testing is to evaluate mass loss and dimensional changes that occurs to the radiological shielding foams when exposed to high temperatures in a muffle furnace. High temperatures often cause materials to undergo physical changes such as swelling or expanding. This is caused by the increase in kinetic energy and atomic and molecular movement.
A battery pack consisting of standard cylindrical 18650 lithium-ion cells has been chosen for small satellite missions based on previous flight heritage and compliance with NASA battery safety requirements. However, for batteries that transit through the International Space Station (ISS), additional certification tests are required for individual cells as well as the battery packs. In this manuscript, we discuss the development of generalized testbeds for testing and certifying different types of batteries critical to small satellite missions. Test procedures developed and executed for this certification effort include: a detailed physical inspection before and after experiments; electrical cycling characterization at the cell and pack levels; battery-pack overcharge, over-discharge, external short testing; battery-pack vacuum leak and vibration testing. The overall goals of these certification procedures are to conform to requirements set forth by the agency and identify unique safety hazards. The testbeds, procedures, and experimental results are discussed for batteries chosen for small satellite missions to be launched from the ISS.
Stochastic Preignition (SPI) is an abnormal combustion phenomenon that can occur in spark-ignition engines particularly under high-load operation. SPI is characterized by uncontrolled initiation of combustion prior to spark discharge, an abnormal combustion process that can lead to severe knock events and significant engine damage. SPI has been associated with fuel properties, lubricant composition, and engine design and operation. Here, in this work, a single-cylinder test engine with a dry-sump oil system was utilized to study the SPI response of E10 and E25 fuels with a range of Reid Vapor Pressure (RVP). An automated test procedure was employed, consisting of ten square-waved load profile segments, with each segment composed of 5 min of low-load operation followed by 25 min of sustained high-load operation. These tests were replicated across multiple days of testing including a lubricant triple flush between tests, and an online Fuel in Oil diagnostic measurement. Exhaust particulate emissions were continuously measured by an AVL microsoot sensor (MSS). Elevated particulate matter emissions were observed to occur concurrently with SPI events as blooms of soot. Particularly after clustered events (i.e., multiple SPI cycles occurring within 10 consecutive engine cycles), high soot emissions were observed to persist over several days of sequential operation despite daily lubricant changes, a complete warm-up procedure, and sustained low-load operation between test segments. This result implies that the particulate emissions trends may be dominated by deposit-based effects, where higher load operation is needed to alter deposition and formation processes. The observed soot blooms were also found to correspond to a reduction in the engine fueling and the fuel engine oil dilution rate despite the engine exhaust remaining at stoichiometric exhaust operation. These observations suggest that post-SPI events, pathways for lubricant migration and consumption into the combustion chamber may occur until these pathways are closed from deposit formation or ring dynamics during extended operation. These observed sooting propensity persisted with all fuels tests, but a linear correlation was observed between the summation of soot and particulate matter index (PMI) value for each fuel as well as SPI events, proving that PMI is a crucial fuel property for reducing SPI.
We present details of a high-accuracy absolute scalar magnetometer based on pulsed proton NMR. The B-field magnitude is determined from the precession frequency of proton spins in a cylindrical sample of water after accounting for field perturbations from probe materials, sample shape, and other corrections. Features of the design, testing procedures, and corrections necessary for qualification as an absolute scalar magnetometer are described. The device was tested at B = 1.45 T but can be modified for a range exceeding 1–3 T. The magnetometer was used to calibrate other NMR magnetometers and measure absolute magnetic field magnitudes to an accuracy of 19 parts per billion as part of a measurement of the muon magnetic moment anomaly at Fermilab.
Shock and vibration tests were performed to determine the electron optical properties of the electron gun. The test procedure included complete mechanical inspection including a dimensional check of all critical parts. Electrical inspection involved tests for dielectric strengths and element to element leakage resistance. All test circuits and equipment for each test are specified in the test plan.
Anhydrous ammonia has been proposed as the working fluid for a number of two-phase thermal control systems to be used in future space applications, including the Space Station Freedom and the Earth Observing Station (EOS). The compatibility of ammonia with the components in these systems is a major concern due to the corrosive nature of the fluid. Compatibility of ammonia with stainless steel and some aluminum alloys is well documented; however, data on other materials potentially suitable for aerospace use is less common. This paper documents the compatibility testing of nine materials with both gaseous and liquid ammonia. The test procedures are presented along with the resulting measurement data. Tensile strength was the only mechanical property tested that indicated a significant material incompatibility.
This report summarizes work performed in setting up and performing tests on a regenerator test rig. An earlier status report presented test results, together with heat transfer correlations, for four regenerator samples (two woven screen samples and two felt metal samples). Lessons learned from this testing led to improvements to the experimental setup, mainly instrumentation as well as to the test procedure. Given funding and time constraints for this project it was decided to complete as much testing as possible while the rig was set up and operational, and to forego final data reduction and analysis until later. Additional testing was performed on several of the previously tested samples as well an on five newly fabricated samples. The following report is a summary of the work performed at OU, with many of the final test results included in raw data form.