A novel use of a telescope to photograph metal diaphragm openings.

A discussion of the fundamentals of the process of underwater electric discharge forming of metals is presented. The deformation of a sheet-metal diaphragm blast gauge is used as a measure of the amount of forming achievable in an experimental research program aimed at determining the effects of major variables on the performance of the electric discharge forming process. The behavior of the diaphragm gauge during forming is analyzed and an equation derived for predicting its maximum deflection when exposed to a given explosion. The predicted dependence of gauge deflection on gauge diameter, thickness, strength and density, and on explosion energy and standoff distance is confirmed by experiment. The application of these results to other forming operations is discussed.

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Electrostatic Analyses for a System Constituted by an Insulating Disk Whose One Plane Surface is Charged and Which is Backed by a Concentric Earthed Metal Disk Smaller Than the Insulating Disk Itself and an Earthed Sphere Approaching the Charged Surface of the Insulating Disk, and Its Application to the Case of a Typical Oxygen Regulator

10.31237/osf.io/qc5ps ◽

2019 ◽

Author(s):

Nirmalya Basu

Keyword(s):

Electric Field ◽

Plane Surface ◽

Dust Particles ◽

Charged Dust ◽

Potential Candidate ◽

Charged Surface ◽

Electrostatic Discharges ◽

Valve Stem ◽

Metal Disk ◽

Metal Diaphragm

There is a proposition that the possible occurrence of electrostatic discharges inside an oxygen regulator between charged insulating components, such as diaphragms, and earthed metal components, such as the valve stem, could be a potential candidate responsible for oxygen regulator fires. In this paper, the electric field which might be produced at the tip of the valve stem due to charge produced on the diaphragm of a typical oxygen regulator by deposition of charged dust particles or by their impact on the diaphragm or both has been evaluated. The diaphragm, in many cases, is backed partially by a concentric earthed metal disk. The diaphragm has been modelled as an insulating disk. The tip of the valve stem has been modelled as an earthed sphere which is very small compared to the insulating disk and the backing earthed metal disk. An analytical expression for the electric field produced at the point of the sphere nearest to the charged surface of the insulator has been derived. Our expression takes into account not only the effect of the charge on the insulating disk, but also that due to the presence of the backing earthed metal disk. Results for the magnitude of this electric field have been computed for the case of a sample oxygen regulator. An expression for the critical charge density on the surface of the insulating disk has been derived, and its value has been obtained for the case of our sample oxygen regulator. The electric field inside the non-metal diaphragm has also been evaluated. It appears from our analyses that there is a possibility that an electrostatic discharge might occur inside an oxygen regulator, and with an enriched-oxygen atmosphere being present there, such a discharge could also lead to a fire incident.

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30 kW metal diaphragm pressure wave generator

10.1063/1.4860874 ◽

2014 ◽

Author(s):

A. Caughley ◽

P. Branje ◽

T. Klok

Keyword(s):

Pressure Wave ◽

Wave Generator ◽

Metal Diaphragm

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On the acoustic disturbances produced by small bodies in plane waves transmitted through water, with special reference to the single-plate direction finder

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1921.0086 ◽

1921 ◽

Vol 100 (704) ◽

pp. 261-288

Keyword(s):

Special Reference ◽

Plane Waves ◽

Maximum Amplitude ◽

Sound Waves ◽

Small Bodies ◽

Acoustic Disturbances ◽

Sense Of Direction ◽

Single Plate ◽

Direction Finder ◽

Metal Diaphragm

The experiments to be described were carried out for the Board of Invention and Research, under the direction of Sir William Bragg, between October 1916 and February 1917, on the Cullaloe Reservoir, near Aberdour, Fifeshire, and are now published with the permission of the Admiralty. A form of directional hydrophone has already been described by Sir William Bragg. It consists of a metal diaphragm, A, about four inches in diameter, mounted in a heavy ring, B, and open to the water on both sides ( vide Chart 9). In the centre of the diaphragm is a small metal box, C, carrying a carbon granule microphone of the button type. The microphone is connected into an ordinary telephone circuit. If the instrument is rotated about a vertical diameter in water through which sound waves are passing the sound heard in the receivers passes through a number of maxima and minima. When the diaphragm is turned “edge-on” to the source of sound it is obvious that the pressure pulses will reach the two faces of the diaphragm symmetrically and the diaphragm will fail to vibrate. As, however, either face is turned toward the source this symmetry ceases to exist and the diaphragm is thrown into vibration, which reaches a maximum amplitude when the instrument is “broad-side” on to the source. The instrument, therefore, indicates the line of propagation of the sound, but owing to the existence of two positions of maximum or minimum its indications are ambiguous as regards the sense of direction.

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Development of 10 inch Diameter Titanium Rolling Metal Diaphragm Tank for Green Propellant

53rd AIAA/SAE/ASEE Joint Propulsion Conference ◽

10.2514/6.2017-4915 ◽

2017 ◽

Author(s):

Harry A. Conomos ◽

Christopher G. Alongi ◽

Jeffrey Moore ◽

Jackie Yager ◽

Richard Goddard ◽

...

Keyword(s):

Green Propellant ◽

Metal Diaphragm

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Investigation on metal diaphragm of pulse separation device in dual-pulse solid rocket motor

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410016638876 ◽

2016 ◽

Vol 231 (3) ◽

pp. 444-451 ◽

Cited By ~ 1

Author(s):

Wang Chunguang ◽

Chen Cong ◽

Ren Quanbin ◽

Chen Ke

Keyword(s):

Rocket Motor ◽

Solid Rocket Motor ◽

Separation Device ◽

Pulse Separation ◽

Single Term ◽

Solid Rocket ◽

Relationship Of ◽

The Relationship ◽

Metal Diaphragm ◽

Physical Dimensions

The theories of circular plates with large deflection and fracture mechanics were employed to investigate the calculating formula of stress intensity factor on prefab gap. The relationship of the opening pressure with physical dimensions of hard pulse separation device (PSD) was analyzed to achieve the feasible configuration of metal diaphragm, which could play a very important role in dual-pulse solid rocket motor. Moreover, six specific single-term tests of the metal diaphragm were conducted to validate the computing precision of designing formula. In addition, three kinds of scale experiments, e.g. the bearing test, opening test, and associated test were performed to explore the working characters of hard pulse separation device. The results indicate that the error between the experimental results and designing results is 4.4%, and the method can be applied to design the physical dimensions of metal diaphragm. The performances of bearing ability, sealability, opening and melt of PSD have been demonstrated. The results show that this kind of PSD can satisfy the requirements of dual-pulse solid rocket motor very well.

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