Propellant condensation on surfaces near an electric rocket exhaust

Reynolds, T. W.; Richley, E. A.

doi:10.2514/3.29779

Cited by 11 publications

(8 citation statements)

References 3 publications

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“…(13). If one neglects the second-order influence of the J 22 contributions to Bj and B 2 , the ratio of orbit angle changes is given by AX r /AX t = 2/3 TT (17) This means that radial thrusting will produce only about one-fifth of the angle change that tangential thrusting can over any given continuous thrusting interval, assuming near-circular orbits. Station relocation can be performed more efficiently (from the standpoint of total impulse required) if one employs high thrust coplanar transfers using two or more impulses.…”

Section: Fig 2 Geosynchronous Station Relocation Phase Planementioning

confidence: 99%

“…Such a system is described in Ref. 17 for the western European region. The system characteristics are summarized in Table 4, and the five-beam cluster is depicted in Fig.…”

Section: Microminiaturized Digital Phase Shifter Configurationmentioning

confidence: 99%

“…A survey of the problems arising from multitransponder operation is given in Ref. 17. In TDMA systems with demand-assigned channel allocation this will be performed most probably by a small processor.…”

Section: Approaches For Future Tdma Systemsmentioning

confidence: 99%

“…(17) and (21) give a new yaw equation, kl -kT ( 2 2 ) This is interpreted as a damped second-order system with forcing functions T^ , kT^, and -kl^, the roll coupling term. This latter term is not desirable because it represents yaw errors resulting from roll transients.…”

Section: Roll/yaw Autopilotmentioning

confidence: 99%

“…Boundary condition analysis of deployed solar array temperature-propellant condensation relations appear in Refs. 5,7,17,19. Electrical effects of films are discussed in Refs.…”

Section: Finally If a Spacecraft Surface Intrudes Far Enough In-mentioning

confidence: 99%

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Communications Satellite Technology

Bargellini¹

1974

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One of the first applications of Earth-orbiting satellites considered was for intercontinental communications.Neither of the other means available--cables and high-frequency radio---completely meets the current requirements of intercontinental communications. A modern system must be capable of furnishing real-time contact between any two points on the Earth whenever the user or customer wants it. It must be reliable and it must be flexible. Cables are reliable but have fixed end points and, therefore, lack flexibility and require a high density of traffic between these points to justify their installation. Highfrequency radio, on the other hand, has the requisite flexibility and can provide communication between any two points having the necessary local fixed equipment; but it leaves much to be desired in reliability.It depends on the ionosphere acting as a reflector to direct the signals over the horizon, and the user is left at the mercy of a highly variable transmission path.Earth-orbiting satellites have, potentially at least, the answers to the shortcomings of both cables and high-frequency radio while still meeting the other requirements of intercontinental communications.Frequencies high enough to be independent of the ionosphere can be used to provide the high reliability without sacrificing the flexibility of high-frequency radio.There were, however, a number of problems to be solved before such a system could be considered practical from an operations viewpoint.A communications satellite system has been compared with a microwave relay system, and the similarities have been stressed.From the engineer's viewpoint, however, the differences are much more substantial.The distance between transmitter and receiver is much greater; the repeater must operate in an environment quite different from that on the Earth's surface, one that even now is not completely defined; the power available at the repeater is severely limited; the entire package must survive hunching and then operate for Before considering specific communications satellites, it is useful to examine the overall system to see how the satellite imposes certain constraints on the other system components and how these constraints affect the application of the system.Two basic types of systems are shown in figure 1.The passive satellite serves to reflect or scatter the signal beamed at it from the transmitting ground station.In this respect its function is the same as that of the ionosphere in the high-frequency radio syskJ' 155 https://ntrs.nasa.gov/search.jsp?R=19640020428 2018-05-10T06:35:50+00:00Z

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Section: Fig 2 Geosynchronous Station Relocation Phase Planementioning

confidence: 99%

“…Such a system is described in Ref. 17 for the western European region. The system characteristics are summarized in Table 4, and the five-beam cluster is depicted in Fig.…”

Section: Microminiaturized Digital Phase Shifter Configurationmentioning

confidence: 99%

Section: Approaches For Future Tdma Systemsmentioning

confidence: 99%

Section: Roll/yaw Autopilotmentioning

confidence: 99%

“…Boundary condition analysis of deployed solar array temperature-propellant condensation relations appear in Refs. 5,7,17,19. Electrical effects of films are discussed in Refs.…”

Section: Finally If a Spacecraft Surface Intrudes Far Enough In-mentioning

confidence: 99%

See 3 more Smart Citations