NOISE PROBLEMS ASSOCIATED WITH LAUNCHING LARGE SPACE VEHICLES
Space vehicle launching and associated noise - saturn launch vehicle - operational problems resulting from vibration
LAUNCHING↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Romie: A Domain-Independent Tool for Computer-Aided Robust Operations Management
Romie is a decision support tool based on AI's latest advances in the domain of robust scheduling. Unlike all its predecessors, the tool allows to (i) visually model the operational problem and context entirely (ii) optimize to find near-optimal schedules while taking uncertainty into account and deals with (iii) a combination of various {key performance indicators (KPIs). It comes with a web user interface. Part or all of the modelled activities may be associated to random variables describing their stochastic durations, in order to produce schedules that are robust w.r.t. temporal uncertainty. Hence, depending on the pursued KPIs, the schedules maximize a combination of the following terms: the probability of satisfying the problem constraints, the expected return/efficiency, the expected outcome quality, and even the operators' wellness by minimizing its expected extra-hours. Initially developed for spatial exploration and demonstration in the context of Mars analog missions, this versatile tool is here applied to operations management in both biotechnology manufacturing and robots parametrization in a cave exploration context.
Chien, Steve A.↗
Operational Experiences with the X-14A Deflected-Jet VTOL Aircraft
During 5 1/2 years of flight research with a deflected-jet VTOL aircraft a 2 number of operational problems were experienced and investigated. These experiences can be grouped into two general categories: (1) the effects of the jet engine and its operation and (2) the restrictions imposed upon the pilot's operation due to reduced visual reference. This report is an examination of these problems and., in some cases, presents possible solutions to these problems.
Rolls, L. Stewart↗
Recent Studies of Runway Roughness
Recent studies of NASA research related to aircraft operating problems on rough runways are presented. Some of these investigations were conducted cooperatively with the airport operators, with the Federal Aviation Agency, and with the U.S. Air Force. The studies show that criteria based on power spectral levels of runway-profile data are not sufficient to define acceptable levels of runway roughness from the piloting viewpoint. Because of the large variation in response characteristics between various types of aircraft, a runway may be acceptable for some aircraft and unacceptable for others. A criterion for roughness, therefore, should be expressed in terms of aircraft response - preferably, cockpit acceleration. A criterion suggested is that the maximum vertical acceleration in the cockpit should not exceed +/- 0.4 g for sections of the runway where precise aircraft control is required.
Morris, Garland↗
Operability engineering in the Deep Space Network
Many operability problems exist at the three Deep Space Communications Complexes (DSCC's) of the Deep Space Network (DSN). Four years ago, the position of DSN Operability Engineer was created to provide the opportunity for someone to take a system-level approach to solving these problems. Since that time, a process has been developed for personnel and development engineers and for enforcing user interface standards in software designed for the DSCC's. Plans are for the participation of operations personnel in the product life-cycle to expand in the future.
Wilkinson, Belinda↗
Space clinical medicine - A prospective look at medical problems from hazards of space operations.
Clinical medical problems of space operation hazards covering hypoxia, decompression, dehydration, weightlessness, radiation, etc
Busby, D. E.↗
Current status and some future test directions for the U.S. National Transonic Facility
The construction of the National Transonic Facility was completed in September 1982 and the start-up and checkout of the tunnel systems were performed over the following two years. In August 1984, the facility was declared operational for final checkout of cryogenic instrumentation and control systems, and for the aerodynamics calibration and testing to commence. Since 1984 several operational problems have been identified and successfully solved which is demonstrated by the fact that the facility has operated the last year with no significant facility down times. Also during this time period, development of test techniques and instrumentation has continued. This paper will review some of the recent test techniques and instrumentation developments, and will briefly review the status of the facility.
Gloss, Blair B.↗
Summary of DM1200 WESP History and Performance
The principal objective of this report was to summarize the testing experience on the DM1200 WESP. Further objectives were to provide descriptions of the history of all modifications and maintenance, methods of operation, problems and unit failures, and performance while processing a variety of feeds, and while employing a variety of operating methods, and to provide comparisons to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) high level waste (HLW) and low activity waste (LAW) WESP designs.
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Summary of DM1200 SBS history and performance
The principal objective of this report is to summarize the testing experience on the DM1200 SBS. Further objectives are to provide descriptions of the history of all modifications and maintenance, methods of operation, problems and unit failures, and performance while processing a variety of feeds, and while employing a variety of operating methods, and to provide comparisons to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) High Level Waste (HLW) and Low Activity Waste (LAW) Submerged Bed Scrubber (SBS) designs.
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 5: OEPSS final briefing for first year study
This study was initiated to identify operations problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advanced Launch System (ALS) Program, the results of the Operationally Efficient Propulsion System Study (OEPSS) were organized into a series of OEPSS Data Books. This volume contains the final briefing on the OEPSS first-year effort. This briefing was presented to MSFC as part of an effort to promote greater interaction between the design community and the launch site operator.
Wong, George S.↗
Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 4: OEPSS design concepts
This study was initiated to identify operations problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advanced Launch System (ALS) program, the results of the OEPSS study have been organized into a series of OEPSS Data Books. This volume describes three propulsion concepts that will simplify the propulsion system design and significantly reduce operational requirements. The concepts include: (1) a fully integrated, booster propulsion module concept for the ALS that avoids the complex system created by using autonomous engines with numerous artificial interfaces; (2) an LOX tank aft concept which avoids potentially dangerous geysering in long LOX propellant lines; and (3) an air augmented, rocket engine nozzle afterburning propulsion concept that will significantly reduce LOX propellant requirements, reduce vehicle size and simplify ground operations and ground support equipment and facilities.
Wong, George S.↗
International Space Station Multi-Element Integrated Test
The International Space Station offers a unique challenge for integrated testing since the entire station is not launched as an integrated vehicle. The ISS design evolved for over 10 years from the station Freedom program that was based on a "ship and shoot" approach. Ship and shoot assumed the program would accept the hardware for launch and integrate the vehicle on orbit without any ground element-to-element integrated testing. Element-to-Element powered-on integrated testing is needed to identify operational problems on the ground rather than once the hardware is on orbit. The industry is accustomed to testing an integrated vehicle and then verifying it is ready for its operational missions. These tests require ground element emulators to represent on-orbit elements. The ISS Multi-Element Integrated Tests (MEIT) are element-to-element integrated tests bringing together hardware representing several flights. The major purpose of these tests is: 1) Element-to-Element interface compatibility, 2) Systems end-to-end operability and functionality and 3) utilize on-orbit procedures with the crew and mission control center. Execution of these tests is critical since the hardware is available for only a limited period of time. Test configurations are defined which test specific interfaces or functionality. These tests develop operational confidence in the Element-to-Element interfaces and identify major problems on the ground to avoid on-orbit anomalies that could threaten mission success, element survivability or assembly activities. This paper addresses the MEIT process, configurations and lessons-learned from these tests.
Filler, Russell E.↗
Study to determine the IFR operational profile and problems to the general aviation pilot
A study of the general aviation single pilot operating under instrument flight rules (GA SPIFR) has been conducted for NASA Langley Research Center. The objectives of the study were to (1) develop a GA SPIFR operational profile, (2) identify problems experienced by the GA SPIFR pilot, and (3) identify research tasks which have the potential for eliminating or reducing the severity of the problems. To obtain the information necessary to accomplish these objectives, a mail questionnaire survey of instrument rated pilots was conducted. Complete questionnaire data is reported in NASA CR-165805, "Statistical Summary: Study to Determine the IFR Operational Profile and Problems of the General Aviation Single Pilot'-Based upon the results of the GA SPIFR survey, this final report presents the general aviation IFR single pilot operational profile, illustrates selected data analysis, examples, identifies the problems which he is experiencing, and recommends further research.
Weislogel, S.↗
Fluorine disposal
A preliminary design of an F2 dispoal system for HELSTF is presented along with recommendations on operational policy and identification of potential operational problems. The analysis is based on sizing a system to handle two different modes of the HELSTF Fluorine Flow System (one operational and one catastrophic). This information should serve both as a guide to a final detailed design for HELSTF as well as a reference for subsequent monitoring and/or modification of the system which consists of a charcoal reactor followed by a dry soda lime scrubber.
Rakow, A.↗
Prediction of solar induced currents and effects on power transmission systems in central Canada
The auroral-electrojet zone covers three quarters of Manitoba and consequently, solar storms strongly affect transmission lines. Harmonics are generated at transformers due to the saturation of their cores by induced currents, and the level of harmonics produced may cause malfunction of control relays, and yield unacceptable distortions in normal ac waveforms. The expected effects of long ac transmission systems were studied with emphasis on a 500 kv line to be built from Winnipeg to Minneapolis-St. Paul. Spectral analysis of induced current records from Manitoba Hydro's LaVerendrye station and magnetograms from IMS stations in Manitoba were used along with results of Campbell's work on the Alaskan pipeline induction problem (1978) in order to predict periodic and surge currents. It is concluded that the surge currents will produce significant levels of harmonics and corresponding operating problems during magnetic storms.
Goddard, W. R.↗
Relaxations of the steady optimal gas flow problem for a non-Ideal gas
Natural gas ranks second in U.S. primary energy consumption. Because most production sites are remote, gas must be transported through pipeline networks equipped with compressors, valves, and other components. For both economic efficiency and system reliability, it is desirable to operate these networks optimally. The governing physics across pipeline components entails nonlinear, non-convex equality and inequality constraints, and the most general steady-flow operations problem is a Mixed-Integer Nonlinear Program (MINLP).This work focuses on one such steady-flow problem-the Optimal Gas Flow (OGF) for a natural gas pipeline network-which minimizes production cost subject to the steady-flow physics. For day-to-day operations, the ability to quickly compute a globally optimal solution and a strong lower bound for varying demand profiles is crucial. A promising strategy is to build tight relaxations of the OGF’s nonlinear constraints. However, many nonlinearities arising from non-ideal equations of state either lack relaxations or have relaxations that do not scale to realistic network sizes. We address this gap by combining recent advances in polyhedral relaxations for univariate functions to construct tight, computationally efficient relaxations of the OGF with a non-ideal equation of state. These relaxations solve within seconds on a standard laptop. In conclusion, we demonstrate their quality through extensive numerical experiments on very large-scale test networks from the literature and find that the proposed approach proves optimality in 92% of tested instances.
03 NATURAL GAS↗
Robust operative diagnosis as problem solving in a hypothesis space
This paper describes an approach that formulates diagnosis of physical systems in operation as problem solving in a hypothesis space. Such a formulation increases robustness by: (1) incremental hypotheses construction via dynamic inputs, (2) reasoning at a higher level of abstraction to construct hypotheses, and (3) partitioning the space by grouping fault hypotheses according to the type of physical system representation and problem solving techniques used in their construction. It was implemented for a turbofan engine and hydraulic subsystem. Evaluation of the implementation on eight actual aircraft accident cases involving engine faults provided very promising results.
Abbott, Kathy H.↗
The development of a solid-state hydrogen sensor for rocket engine leakage detection
Hydrogen propellant leakage poses significant operational problems in the rocket propulsion industry as well as for space exploratory applications. Vigorous efforts have been devoted to minimizing hydrogen leakage in assembly, test, and launch operations related to hydrogen propellant. The objective has been to reduce the operational cost of assembling and maintaining hydrogen delivery systems. Specifically, efforts have been made to develop a hydrogen leak detection system for point-contact measurement. Under the auspices of Lewis Research Center, the Electronics Design Center at Case Western Reserve University, Cleveland, Ohio, has undertaken the development of a point-contact hydrogen gas sensor with potential applications to the hydrogen propellant industry. We envision a sensor array consisting of numbers of discrete hydrogen sensors that can be located in potential leak sites. Silicon-based microfabrication and micromachining techniques are used in the fabrication of these sensor prototypes. Evaluations of the sensor are carried out in-house at Case Western Reserve University as well as at Lewis Research Center and GenCorp Aerojet, Sacramento, California. The hydrogen gas sensor is not only applicable in a hydrogen propulsion system, but also usable in many other civilian and industrial settings. This includes vehicles or facility use, or in the production of hydrogen gas. Dual space and commercial uses of these point-contacted hydrogen sensors are feasible and will directly meet the needs and objectives of NASA as well as various industrial segments.
Liu, Chung-Chiun↗