TFE coating extends life of flexible metal compressor diaphragm

Tetrafluoroethylene /TFE/ aerosol sprayed onto entire surface of diaphragm acts as film lubricant and permits diaphragm to slide between upper and lower plates in a reciprocating compressor. Flexing occurs over an area rather than about a single line of action and operating life of diaphragm is more than quadrupled

Results from Symposium on Future Orbital power systems technology requirements

The technology requirements for future orbital power systems were reviewed. Workshops were held in 10 technology disciplines to discuss technology deficiencies, adequacy of current programs to resolve those deficiencies and recommendations for tasks that might reduce the testing and risks involved in future orbital energy systems. Those recommendations are summarized

Radiation exposure and performance of multiple burn LEO-GEO orbit transfer trajectories

Many potential strategies exist for the transfer of spacecraft from low Earth orbit (LEO) to geosynchronous (GEO) orbit. One strategy has generally been utilized, that being a single impulsive burn at perigee and a GEO insertion burn at apogee. Multiple burn strategies were discussed for orbit transfer vehicles (OTVs) but the transfer times and radiation exposure, particularly for potentially manned missions, were used as arguments against those options. Quantitative results concerning the trip time and radiation encountered by multiple burn orbit transfer missions in order to establish the feasibility of manned missions, the vulnerability of electronics, and the shielding requirements are presented. The performance of these multiple burn missions is quantified in terms of the payload and propellant variances from the minimum energy mission transfer. The missions analyzed varied from one to eight perigee burns and ranged from a high thrust, 1 g acceleration, cryogenic hydrogen-oxygen chemical prpulsion system to a continuous burn, 0.001 g acceleration, hydrogen fueled resistojet propulsion system with a trip time of 60 days

Control of contaminants in liquid-metal systems

Contaminant controls and cleaning procedures in SNAP-8 simulation loop of liquid metal

Space R/T base: Propulsion (high thrust chemical)

The topics presented are covered in viewgraph form. The programmatic objective is to provide a technology base and maintain an institutional capability for continued advances in the development of advanced space propulsion systems to support launch, upper stage, orbit transfer and ascent/descent engines. The technical objectives are to study: (1) validated design and analytical codes for cryogenic turbopump bearings and seals; (2) design methodologies and diagnostic capabilities for combustion stability; and (3) reduced operations cost, increase life, safety, higher energy density propellants, and in-situ engine concepts

Continuous monitor for gas ratios in a mixture

Fluidic oscillator, incorporating piezoelectric transducer to sense molecular weight of gas mixture, is used to continuously monitor ratio of a mixture of two gases in a flowing system. Device is lightweight, compact, reliable, easy to install, and also produces a simple output signal for controller. Frequency of oscillation is measured and signal converted to ac output

Transportation technology: Earth-to-orbit propulsion

The topics presented are covered in viewgraph form and include the following: (1) sensor autodiagnosis and autocalibration; (2) autodiagnostic and autocalibration program; (3) plume diagnostics; (4) plume diagnostics program; (5) failure modeling; (6) mass data storage and retrieval; (7) fiber optic instrumentation bus; (8) model based diagnostics; (9) safety monitoring system (SMS); (10) control and real time diagnostics; (11) current intelligent controls program; (12) augumented intelligent controls program; (13) current real time diagnostics program; (14) augumented RT diagnostics program; and (15) control and diagnostic system hardware

Performance and evaluation of two liquid-metal pumps for sodium-potassium service

Performance tests on liquid metal pumps for sodium potassium loop