Abstract: A powder sample inspection cell assembly comprising a cell, an aperture being provided in a side wall of the cell; a closure member which can be clamped over the aperture to close it; and means for compacting the contents of the cell, the cell being oriented such that, after compaction, powder in the cell is sufficiently compacted so as not to escape through the aperture when the closure member is removed.

Abstract: A fluid-tight coupling and sealing arrangement including a flexible joint for coupling a tube with pressurized fluid flowing therethrough to another tube or a fluid device. The flexible joint basically includes a first tubular member with an outer restraining member coupled thereto, a second tubular member, and a pressure-energized seal positioned between the first and second tubular members. The first tubular member has a first fluid passageway and a first annular sealing surface. The second tubular member has a second fluid passageway, a second annular sealing surface, and an outwardly facing bearing surface. The outer restraining member carries an inwardly facing bearing surface for engaging the outwardly facing bearing surface of the second tubular member.

Abstract: An arcjet thruster is disclosed which has an electrically conductive anode body having an anode cavity therein which defines a nozzle symmetrical about a central axis. The anode cavity has a tandemly arranged divergent recombination portion and a divergent expansion portion. The expansion portion has a greater rate of divergence than the recombination portion. The anode body further preferably comprises a cylindrical constrictor portion upstream and in tandem with the recombination portion. An electrically conductive cylindrical cathode body is coaxially arranged and spaced from the anode body by a gap. An electrical current source connected to the cathode and the anode produces an electrical arc across the gap. A vortex flow of propellant gas is fed through the gap and through the nozzle to produce thrust. The vortex flow of propellant gas pushes the arc through the constrictor into one of the divergent portions of the nozzle.

Abstract: An arcjet thruster has a body defining a constrictor and nozzle constituting an anode and forming an arc chamber. An elongated rod constitutes a cathode spaced from the constrictor by a gap generally coextensive with the arc chamber. An electrical potential is applied to the anode and cathode to generate an electrical arc in the arc chamber from the cathode to the anode. Propellant is supplied to the arc chamber with generation of the arc so as to produce thermal heating and expansion of the propellant through the nozzle. The thruster employs several features which improve its performance. One feature relates to the use of propellant blends with high specific impulse additives. Another feature relates to injection of the high specific impulse additive into the bulk propellant feed at the region of the cathode tip.

Abstract: An arcjet thruster has a body defining a constrictor and nozzle constituting an anode and forming an arc chamber. An elongated rod constitutes a cathode spaced from the constrictor by a gap generally coextensive with the arc chamber. An electrical potential is applied to the anode and cathode to generate an electrical arc in the arc chamber from the cathode to the anode. Propellant is supplied to the arc chamber with generation of the arc so as to produce thermal heating and expansion of the propellant through the nozzle. The thruster employs several features which improve its performance. One feature relates to the use of propellant blends with high specific impulse additives. Another feature relates to injection of the high specific impulse additive into the bulk propellant feed at the region of the cathode tip.

Abstract: An arcjet thruster has an anode body forming a constrictor and a nozzle which define an arc chamber. The thruster also has a cathode in the form of a rod having a tip and being spaced upstream from the constrictor. The thruster employs several features which reduce anode and cathode erosion and increase the operational life of the thruster. One set of features relate to the employment of cathode and anode shaping. Another feature relates to the use of a propellant injector having a series of radially and tangentially arranged passages for providing direct injection of propellant gas into the arc chamber and enhanced convective cooling of the anode.