US2939048A

US2939048A - Apparatus for creating extremely high temperatures

Info

Publication number: US2939048A
Application number: US738854A
Authority: US
Inventors: Ralph W Waniek
Original assignee: Plasmadyne Corp
Current assignee: Plasmadyne Corp
Priority date: 1958-05-29
Filing date: 1958-05-29
Publication date: 1960-05-31
Anticipated expiration: 1977-05-31

Description

May 31, 1960 R. w. WANlEK 2,939,048

APPARATUS FOR CREATING EXTREMELY HIGH TEMPERATURES Filed May 29, 1958 nan/5e NM sol/ear:

re/eee' /7 041 M Wfl/V/EK INVENTOR.

APPARATUS FOR CREATING EXTREMELY TENHERATURES Ralph W. Waniek, Weston, Mass., assignor, by mesne assignments, to Plasmadyne Corporation, Santa Ana, Califi, a corporation of California Filed May 29, 1958, Ser. No. 738,854

8 Claims. (Cl. 315-236) HIGH electrically-conductive surface which forms the wall of a generally spheroidal cavity, the electrical conductor of vapors of impurities are very high. It follows that a large amount of the energy stored in the discharge is dissipated in the form of radiation, thereby reducing the effective temperature of the gas.

With relation to devices which effect discharges in space, that is to say without electrodes, these conventionally consist of a toroidal chamber which produces, in conjunction with magnet means and by virtue of a pinch effect, a toroidal plasma concentration of filamentlike dimensions. The energy stored in this pinch of plasma is readily radiated because of the geometry of the apparatus. For this and other important reasons, such apparatus has been characterized by limitations as to the maximum temperature which may be achieved, it being diflicult to supply energy at a rate sufficiently fast to permit the attaining of ultra high temperatures. Other limitations and defects of such toroidal-type plasma devices have included various forms of plasma instabilities.

In view of the above factors characteristic of dischargetype devices for obtaining extremely high temperatures, it is an object of the present invention to provide an apparatus for creating a very high temperature in a small volume approximating a point, and in a highly efiicient manner.

A further object of the invention is to provide electrical-conductor means for creating a substantially continuous electrically-conductive surface defining a generally spheroidal cavity, in combination with means'to effect flow of a single very high current pulse through said electrical conductor, thereby creating a concentric blast or shock in said cavity to produce a high concentration of ionized particles at the center thereof.

These and other objects and advantages of the invention will be more fully set forth in the following specification and claims, considered in connection with the attached drawing to which they relate.

In the drawing:

Figure l is a perspective view of one form of apparatus constructed in accordance with the present invention; and

Figure 2 is a section taken on line 2-2 of Figure 1, and showing in schematic form an electric circuit means associated with the electrical conductor which defines the cavity.

Stated generally, the apparatus comprises electrical conductor means to define a substantially continuous,

means being split to form a gap along one great seinicircle of the cavity. Means are provided for momentarily supplying large amounts of electrical current to the electrical conductor means on opposite sides of the gap or split. This effects a momentary, single-turn flow of current around the cavity to cause a high concentration of ionized particles at the center portion thereof.

' Stated more definitely, the high concentration of ionized particles at the center portion of the cavity, in a volume approaching a point, results from the extremely rapid rate of change of magnetic field strength due to the low inductance of the electrical conductor and the large amount of current passed instantaneously therethrough. Because of the rapid rate of change of magnetic field strength, ionized particles in the cavity are accelerated rapidly toward the center and form an inwardly-directed shock, or a spherical implosion. The rapid acceleration of the ionized particles, and the collision thereof in the region of the center, provides a very high temperature on the order of millions of degrees.-

Referring to the drawing, the apparatus comprises a' relatively strong and thick hollow conductor, illustrated as a ball or spheroid '10 formed of copper alloys or other highly conductive material.

somewhat irregular, but the inner surface 11 should be a relatively smooth, roundedsurface having the general shape of a spheroid. The inner surface defines within it a cavity 12 which should be substantially evacuated to achieve the selected-operating pressure. In order to maintain this vacuum, a hollow spherical envelope 13', formed of a non-conductor such as quartz, is provided in cavity 12., and preferably has its outer surface closely adjacent the inner surface 11 of conductor element 10.

The conductor 10 may also comprise a thick mass of copper, preferably a strong allow such as hardened beryllium-copper, which is not externally spherical. Such mass may be shaped as a block of metal having a spher-' oidal cavity carved therein. The block is split along one great semicircle of the cavity in order to provide a single-- single split or gap 14 along one great semicircle thereof,-

the remainder of the conductor being continuous. vT he' gap 14 is sufficiently wide (or insulated) to prevent arcing thereacross under the voltage impressed thereon. In order to conduct current to the ball 10 on opposite sides of gap 14,

plates

16 and 17 are associated with the ball 10 and extend outwardly therefrom generally parallel and close to each other. preferably integral with the spheroid, are also spaced apart (or insulated) to prevent arcing due to the int! pressed voltage.

Plates

16 and 17 are preferably located very close to each other, in order to minimize inductance, and may be maintained electrically separate by -a thin sheet of insulation. It is pointed out that

theplates

16 and 17, and the conductive ball 10, provide the previously-indicated single-turn continuous circuit 'around the evacuated cavity 12 and through which a large current may fiow. Because of the single-turn nature'of the cir- Paten ted May 31, 1 960 The outer surface of the ball or spheroid is notnecessarily round and may be

Plates

16 and 17, which are the. .e1ements.10, 16 and 17 such asby embeddingthe amount of current through the single-turn circuit is shown as comprising a capacitor 21 connected between the plates ;16 and 17 by means of conductors 22 and'23. Thencapacitor is charged from a suitable power source 24, ,such as a direct current generator, and is discharged underthecontrol of a trigger or switch means 26 which is; illustrated ,as interposed in the lead 23 between capacitor 2 l-and plate ,17. It is; to be understood that the showing. of the electric circuit means at the right in Figure 2 is highly schematic, and that the capacitor 21, the: associated leads ,22 and 23, etc., are normally very with openings-(or non-conductors) at the polesofthe perature because of the speed and collision of the pan ticles. The inward movement continues until the external magnetic pressure is counterbalanced by the internal pressure resulting from compression and temperature increase.

Since the lines of magneticforce may not pass through the electrical conductor metal, the conductor is provided cavity. The lines of force thusflow through the poles and externally of the'sp'heroid to form continuous loops. As-previouslyindicated,the reinforcing material in which the apparatus is embeddedis non-conductive (except possibly in a casingremote from'the sphere) and thus does large and-of a low-inductance type adapted to generate the-above-indic-ated large current upon discharging. Inthp'operation ofthe apparatus, capacitor means 21 is first charged fromthe power source 24 when the trigger or switch means 26 is in open-circuit condition. Thereafter, the trigger 26 is operated to close the circuit from the capacitor 21 to

plates

16 and 17. A single very large current then flows in a single turn around the hollow spheroid 10, but only for the short period of time required to discharge the capacitor means 21. Because of the. very high rate of change of current, the current flow. tends to concentrate at the inner surface 11 due toskin effect.

The result of the above is a very rapidly changing magnetic field within cavity 12, and having a very great strength suflicient to effect rapid acceleration of ionized particlestoward the center portion of the cavity. Therapidacceleration and speed of the ionized particles, and

the collision of theparticles, produce an extremely high temperature at the center portion of the cavity. Stated otherwise, a pulsed magnetic field is generated whichis such .as toetfect a radially inwardly directed shock creating-the-very high temperature at a small volume at the center portion of the spheroid, approaching a point,

To upon the previously-stated theory relative to the present invention, it is pointed out that the flow of. current is in a given direction through the conductor means and circumferentially about the axis of the sphe roiclal cavity. This results in the formation of an induced current sheet flowing in the opposite direction and through the gas. The induced current sheet is located within the evacuated cavity and is initially relatively close to the cavity wall formed by the conductor means, Thus, in the situation in which there is an envelope within the cavity, the induced current initially flows through the gas adjacent the inner wall of the envelope, it being remembered that the envelope is formed of non-conductive material.

The sheet of induced current, composed of ions and electrons, acts as a barricade through which the lines of magnetic force may not penetrate appreciably. This is particularly true when the rate of change of magnetic field strength is great. This being the case, at least the; majority of lines of magnetic force initially pass (in a spheroidal configuration) between the conductor metal and the current sheet-or largely throughthe envelope.

in cases where there is an envelope.

The generally spheroidal magnetic field acts as a piston todrive (implode) the current sheet, that is to say the ions and electrons, radially inwardly toward the center of the cavity. As the current sheet collapsestoward the center, in a shock wave, the lines of magnetic force collapse toward the center (in the above-indicated piston;

action) to compress the gas, and greatly elevate its tern! manner, such as by p assingradio-frcquency waves through;

the-cavity. For example, electrodes may be located near (but outside) he openingat each pole, and energized by Pre-ionization increases the a radio-frequency oscillator. 7 electrical conductivity of the gas, and thus the amount of current flowin the current sheet. Such increased flow.

in the current sheet aids in preventing initial penetration of the magnetic field into the body of the ionized gas. A; very eflicient and effective piston action is thus. achieved, with consequent rapid inward acceleration of theions and electrons.

An alternative means of achieving pre-ionization isto inject an ionized cloud of gas into cavity 12, and immediately subject it to magnetic compression in accordance with the principles set forth herein.

It is'emphasized that the present invention produces a relatively stable concentration of high-temperature plasma. near the center of the cavity. The plasma is stable be-- cause the magnetic field is generated by the flow of current through the metal conductor. This is to be contrastedwith pinch-type devices, in which the constrictof; capacitors. Suchrepetitive operation, if at a sufficiently high;;frequency, may improve the heating eifect on the gas,

It is to;beunde1 stood that the terms point, approximating a point, etc., do not mean that the high: temperatureoccurs only at a geometrical point. What is meant is'that the highest concentration of plasma is in a. small volume,- as close to a point as possible. There may, however, be plasma concentrations of lesser densityv at regions other than the center of the cavity.

The cavity 12, c0nductor '10', etc., need not be perfectly spherical but may, as previously indicated, be generally spheroidal. For example, the ball may be oblate or prolate, as requiredjto effect optimurn magnetic field conditions in; the cavity 12. Throughout the Specifica-, tion and claims, the use of the term spheroid includes not only elements which approach-spheres, but also perfect spheres. I

Various embodiments of the present invention, in addition to what has beenillustrated and described in detail, may be employed without departing from the scope of the accompanying claims.

I claim; '1.- Apparatusfor generating an extremely high temperature which comprises electrical conductor means to define a ge nerallyspheroidal cavity, saidelectrical conduster mea ein n n s u said. v y, x:

cept for a single split or gap separating said electrical conductor means into a single-tum, continuous electric circuit around said cavity.

2. Apparatus for creating a very high temperature, comprising a continuous, unitary electrical conductor shaped generally as a hollow spehroid having a split or gap around only one great semicircle thereof, said split or gap being sufiiciently wide to prevent arcing thereacross under normal impressed voltages, means to maintain a substantial vacuum within the cavity in said hollow spheroid, and separate plate means electrically connected to said spheroid on opposite sides of said gap and extending outwardly therefrom for use in supplying electrical current to said spheroid on one side of said gap so that said current may flow around said spheroid and out the plate means on the other side of said gap.

3. The invention as claimed in claim 2, in which said plate means have widths substantially equal to the diameter of said spheroid, whereby current is supplied to and removed from said spheroid throughout substantially the entire edges of said spheroid at said gap.

4. Apparatus for generating an extremely high temperature, which comprises a block or mass of electricallyconductive material having a cavity therein, the wall of said block or mass which defines said cavity being generally spheroidal in shape, said block or mass being formed with a single split or gap along one great semicircle of said generally spheroidal wall, means to maintain a substantial vacuum in said cavity, and electrical conductor means connected to said mass at points adjacent opposite sides of said split or gap to efiect current flow through said mass in a single-tum, continuous circuit around said cavity.

5. The invention as claimed in claim 4,- in which said conductor means comprise generally parallel plates provided integrally with said mass on opposite sides of said split or gap, the widths of said plates approximating the diameter of said cavity.

6. Apparatus for generating an extremely high temperature, which comprises a continuous block or mass of electrically-conductive material having a cavity therein, the walls of said block or mass which defines said cavity being generally spheroidal in shape, said mass or block being :formed with a single split or gap along one great semicircle of said generally spheroidal wall, means to maintain a substantial vacuum in said cavity, separate electrical conductor means connected to said mass at points adjacent opposite sides of said split or gap to effect current flow through said mass in a continuous, single-turn circuit around said cavity, and means to momentarily supply a very large current to the con ductor means on one side of said split or gap to effect flow of current through said conductor means and through said block or mass around said cavity to the conductor means on the other side of said split or gap.

7. The invention as claimed in claim 6 in which said last-named means comprises capacitor means connected between said conductor means on opposite sides of .said split or gap, means to charge said capacitor means, and trigger means to eifect discharge thereof.

8. Apparatus for generating very high temperatures in a small volume approximating a point, comprising a thick-walled continuous hollow spheroid formed of highly conductive metal, such spheroid having a spheroidal cavity therein, envelope means to define an evacuated chamber in said cavity, split or gap means provided only along substantially one entire great semicircle of said spheroid, plates formed integrally with said spheroid at opposite sides of said split or gap means and extending outwardly therefrom, said plates extending for substan ti'ally the full diameter of said spheroid, capacitor means connected across said plates, and means to discharge said capacitor means into said plates and thus in a singleturn circuit through said spheroid around said cavity to thereby eifect an inwardly-directed blast of ionized particles in said cavity with consequent generation of a high temperature at the center portion thereof.

References Cited in the file of this patent UNITED STATES PATENTS Bethenod Mar. 7, 1939 Notice of Adverse Decision in Interference In Interference No. 95,080 involving Patent No. 2,939,048, R. W. VVaniek, APPARATUS FOR CREATING EXTREMELY HIGH TEMPERA- TUBES, final judgment adverse to the patentee was rendered Mar. 7 1966, as to claim 1.

[Oflicial Gazette May 17, 1966.]

Notice of Adverse Decision in Interference In Interference No. 95,080 involving Patent No. 2,939,048, R. VVaniek, APPARATUS FOR CREATING EXTREMELY HIGH TEMPERA- TUBES, final judgment adverse to the patentee was rendered Mar. 7, 1966, as to claim 1.

[Ofiicial Gazette May 17, 1966.]