Some mapping properties of rc and rl driving- point impedance functions.
Mapping properties of RC and RL driving point impedance functions in right half of frequency plane
MAPPING↗
SEARCH · Engineering Papers
Results for “RL”
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
RC-RL decomposition of a fourth-order polynomial
Fourth order polynomial RC-RL decomposition conditions
Chan, S. P.↗
Stress relaxation and mechanical properties of RL-1973 and PD-200-16 silicone resin sponge materials
Stress relaxation tests were conducted by loading specimens in double-lap shear to a preselected strain level and monitoring the decay of stress with time. The stress relaxation response characteristics were measured over a temperature range of 100 to 300 K and four strain levels. It is concluded that only a slight amount of stress relaxation was observed, and the stiffness increased approximately two orders of magnitude over the range of temperatures.
Saylak, D.↗
Deep RL for Fast Long-Horizon Operations Scheduling on NASA's Carruthers Geocorona Observatory Mission
Spacecraft operations scheduling is a highly constrained, long-horizon combinatorial optimization problem that traditionally relies on heuristics, constraint programming, or manual planning. We present a scalable deep reinforcement learning framework developed and deployed for NASA’s Carruthers Geocorona Observatory mission. Our framework introduces a macro-action abstraction known as activity blocks coupled with dynamic action-masking to navigate the intractably large search space and strictly enforce complex power, thermal, and instrument constraints. The resulting architecture generates globally feasible schedules with overwhelming probability, establishes operational trust, and executes a full training cycle in under six hours, circumventing the need for policy robustness by enabling rapid, on-demand retraining. Further, resulting schedules outperform baseline heuristics in scheduled science quality. The deep reinforcement learning framework was deployed as the default operational scheduler for the Carruthers Geocorona Observatory mission from the outset of the mission, demonstrating that deep reinforcement learning can be trusted for real spacecraft operations under complex, evolving constraints.
Geocorona↗
Design study of RL10 derivatives. Volume 2: Engine design characteristics, appendices
Calculations, curves, and substantiating data which support the engine design characteristics of the RL-10 engines are presented. A description of the RL-10 ignition system is provided. The performance calculations of the RL-10 derivative engines and the performance results obtained are reported. The computer simulations used to establish the control system requirements and to define the engine transient characteristics are included.
Source record↗
Photographic Study of Liquid-Oxygen Boiling and Gas Injection in the Injector of a Chugging Rocket Engine
High-speed motion pictures were taken of conditions in the injector liquid-oxygen cavity of an RL-10 rocket engine during throttled engine operation. Photographs were taken during operation of the engine in the chugging region as the helium gas was injected to stabilize combustion, during operation at rated thrust, and during transition into chugging conditions as the gas injection was discontinued. Results of the investigation indicate that, during chugging rocket operation of the RL-10 engine, a high population of fairly large bubbles formed and collapsed within the liquid-oxygen cavity at the same frequency as the chamber pressure oscillations. When gaseous helium was injected into the liquid-oxygen cavity, a fog rapidly spread over the entire field of view, and the system immediately became stable. The injection of gaseous helium at rated conditions produced a very slight increase in engine performance but not enough to produce a net gain in a typical mission payload with the extra equipment needed. The inherent low-frequency system instability associated with the fuel system at low thrust levels was reduced by injecting either gaseous helium or hydrogen. Complete stabilization was achieved in some cases, and a reduction in the severity of the oscillations in others. This was apparently due to the ·anchoring of the phase change front to the location of the gas injection.
Conrad, E. William↗
Design study of RL10 derivatives. Volume 2: Engine design characteristics
The design characteristics of the RL-10 rocket engine are discussed. The results from critical elements evaluation, baseline engine design, parametric and special study tasks are presented. Critical element evaluation established the feasibility of various engine features such as tank head idle, pumped idle, autogenous tank pressurization, and two-phase pumping. Three baseline engines, derived from the RL-10 were conceptually designed. Parametric life and performance data were generated. Special studies were conducted to establish the impact on the engine design of environment, safety, interchangeability, and maintenance.
Adams, A.↗
Orbit transfer vehicle engine study. Volume 2: Technical report
The orbit transfer vehicle (OTV) engine study provided parametric performance, engine programmatic, and cost data on the complete propulsive spectrum that is available for a variety of high energy, space maneuvering missions. Candidate OTV engines from the near term RL 10 (and its derivatives) to advanced high performance expander and staged combustion cycle engines were examined. The RL 10/RL 10 derivative performance, cost and schedule data were updated and provisions defined which would be necessary to accommodate extended low thrust operation. Parametric performance, weight, envelope, and cost data were generated for advanced expander and staged combustion OTV engine concepts. A prepoint design study was conducted to optimize thrust chamber geometry and cooling, engine cycle variations, and controls for an advanced expander engine. Operation at low thrust was defined for the advanced expander engine and the feasibility and design impact of kitting was investigated. An analysis of crew safety and mission reliability was conducted for both the staged combustion and advanced expander OTV engine candidates.
Source record↗
Saturn i launch vehicle sa-8 and launch complex 37b functional systems description. volume ix- rl10a-3 engine and hydraulic system functional description, index of finding numbers, and mechanical schematics
Saturn I /SA-8/ launch vehicle and Launch Complex 37B - RL-10 A-3 engine and hydraulic system
HYDRAULIC EQUIPMENT↗
Saturn i launch vehicle sa-10 and launch complex 37b functional systems description. volume ix- rl10a-3 engine and hydraulic system functional description, index of finding numbers, and mechanical schematics
Saturn I /SA-10/ launch vehicle and Launch Complex 37B - RL-10 A-3 engine and hydraulic systems
RL-10 A-3 ROCKET ENGINE↗
Apollo vehicle propulsion systems.
H-1, F-1, J-2 and RL-20 Apollo vehicle propulsion systems must have preflight design maturity due to man-rating requirement
PROPULSION SYSTEM PERFORMANCE↗
RL10A-3-3 rocket engine Design report
Design features of RL-10 A-3 liquid propellant rocket engine
RL-10 A-3 ROCKET ENGINE↗
Development of LOX-hydrogen engines for the Saturn Apollo launch vehicles.
RL-10 and J-2 hydrogen oxygen engine design and development for Saturn Apollo launch vehicles, noting performance parameters from ground and flight tests
Burks, A. J.↗
FLOX/methane pump-fed engine study
FLOX and methane rocket propellant for use with modified RL-10-A-1 engine
Bailey, T. E.↗
FLOX/methane pump-fed engine systems.
Flox/methane pump fed engine, discussing RL-10-1-A engine tests and optimized 5000 lb thrust engine design
Brooke, A. W.↗
Low speed inducers for cryogenic upper stages
Briefing charts are presented, which were used in an oral presentation of the results and recommendations for the design and analysis of low speed hydrogen and oxygen inducers and their drive systems applicable to the space tug. A discussion of the design of the 15K and RL-10 inducers is included.
King, J. A.↗
Propulsion system tests on a full scale Centaur vehicle to investigate 3-burn mission capability of the D-lT configuration
Propulsion system tests were conducted on a full scale Centaur vehicle to investigate system capability of the proposed D-lT configuration for a three-burn mission. This particular mission profile requires that the engines be capable of restarting and firing for a final maneuver after a 5-1/2-hour coast to synchronous orbit. The thermal conditioning requirements of the engine and propellant feed system components for engine start under these conditions were investigated. Performance data were also obtained on the D-lT type computer controlled propellant tank pressurization system. The test results demonstrated that the RL-10 engines on the Centaur vehicle could be started and run reliably after being thermally conditioned to predicted engine start conditions for a one, two and three burn mission. Investigation of the thermal margins also indicated that engine starts could be accomplished at the maximum predicted component temperature conditions with prestart durations less than planned for flight.
Groesbeck, W. A.↗
Centaur feedline dynamics study using power spectral methods
Tests were conducted to determine the dynamic characteristics of the Centaur/RL-10 oxygen and hydrogen feedlines. The fundamental-mode resonant frequencies were determined by applying power spectral methods to noise-generated data from hot firings of the RL-10 engine. The effect of net positive suction pressure of the main feed pumps on resonant frequency characteristics was determined to be a straight-line relation. Power spectral methods were also used to determine the dynamic characteristics of the boost pumps.
Lorenzo, C. F.↗