US-20260128183-A1 - System and Method for Energy Recovery in a Beam Collider

US20260128183A1US 20260128183 A1US20260128183 A1US 20260128183A1US-20260128183-A1

Abstract

Energy-recovery system and method for a beam collider. A first ion beam and a second ion beam are directed within an active space along a first path and a second path, respectively. Each ion beam has essentially uniform energies of ions within each ion beam, and essentially uniform velocity vectors of ions within each beam at points within each path of each respective ion beam. The first and the second ion beams are caused to collide substantially head-on with each other within a collision zone in the active space, where the ratio of the energy of the ions of the first beam to the energy of the ions of the second beam equals the inverse ratio of the respective ion masses. Energy of the scattered ions of the first ion beam and the second ion beam is recovered, and cold ions are evacuated from the active space.

Inventors

Evgueni Tsiper

Assignees

Evgueni Tsiper

Dates

Publication Date: 20260507
Application Date: 20251230

Claims (20)

1 . An energy recovery system for a beam collider that accelerates and collides beams of hot ions, the beam collider including a vacuum chamber that defines an interior, at least one ion injection port, and a plurality of electrodes that, when energized, are configured to form an ion beam focusing arrangement that produces, in an active space of the interior, a first ion beam of hot ions and a second ion beam of hot ions from ions injected via the at least one ion injection port, and wherein the ion beam focusing arrangement directs the ion beams to overlap and cause collisions of some of the hot ions of the first and the second beams within a collision zone in the interior, the energy recovery system comprising: a vacuum pump coupled to the vacuum chamber, the vacuum pump configured to maintain a vacuum in the interior; an ion energization circuit coupled to the plurality of electrodes and configured to energize the electrodes to form the first and the second ion beams which are directed head-on with one another with uniform energies and uniform velocity vectors of the hot ions within each ion beam, wherein a ratio of the energy of the ions of the first beam to the energy of the ions of the second beam equals the inverse ratio of the respective ion masses in the head-on collisions; a first energy recovery electrode coupled with the ion energization circuit and positively biased based on known energy of scattered ions of the first ion beam that are scattered as a result of the collisions in the collision zone, the energy of the scattered ions being known based on the ratio of the energy of the ions of the first beam to the energy of the ions of the second beam being equal to the inverse ratio of the respective ion masses, the first energy recovery electrode being configured to slow down the scattered ions, and transfer kinetic energy of those scattered ions to the ion energization circuit, to produce a first set of cold ions that are evacuated from the active space.
2 . The energy recovery system of claim 1 , wherein the first energy recovery electrode comprises an ion-permeable construction to permit the first set of cold ions to pass through the first energy recovery electrode.
3 . The energy recovery system of claim 1 , wherein the first energy recovery electrode comprises an ion-absorbing material.
4 . The energy recovery system of claim 1 , wherein the first energy recovery electrode is arranged such that the scattered ions impinge on the first energy recovery electrode at an angle that is normal to the first energy recovery electrode.
5 . The energy recovery system of claim 1 , further comprising: a second energy recovery electrode coupled with the ion energization circuit, the second energy recovery electrode being positively biased according to known energy of scattered ions of the second ion beam that are scattered as a result of the collisions in the collision zone, the energy of the scattered ions being known based on the ratio of the energy of the ions of the first beam to the energy of the ions of the second beam being equal to the inverse ratio of the respective ion masses, and wherein the second energy recovery electrode is operative to transfer sufficient kinetic energy of scattered ions of the second ion beam to the ion energization circuit to produce a second set of cold ions that are evacuated from the active space.
6 . The energy recovery system of claim 1 , further comprising: a cold ion evacuation system arranged to remove the first set of cold ions from the active space.
7 . The energy recovery system of claim 6 , wherein the cold ion evacuation system includes the vacuum pump.
8 . The energy recovery system of claim 1 , further comprising: an acceleration electrode situated proximate the collision zone, wherein the acceleration electrode is negatively biased and arranged to accelerate ions of the first and the second ion beams towards the collision zone, and to decelerate any non-collided ions of the first and the second ion beams as those non-collided ions pass by the collision zone.
9 . The energy recovery system of claim 1 , wherein the first ion beam comprises a first species of ions, and the second ion beam comprises a second species of ions that is different from the first species.
10 . The energy recovery system of claim 1 , wherein the first energy recovery electrode is under-biased by a potential difference sufficient to reduce a quantity of scattered ions that would otherwise reverse direction of their motion, and return to the collision zone.
11 . A method of recovering energy in a beam collider that accelerates and collides beams of hot ions within a vacuum chamber having an interior that includes an active space and a collision zone, the beam collider including at least one ion injection port and a plurality of electrodes operable to form an ion beam focusing arrangement, the method comprising: maintaining a vacuum in the interior of the vacuum chamber; injecting ions into the interior via the at least one ion injection port; energizing, with an ion energization circuit, the plurality of electrodes to form, in the active space, a first ion beam of hot ions and a second ion beam of hot ions from the injected ions; controlling the ion beam focusing arrangement to direct the first ion beam and the second ion beam head-on with one another such that ions within each of the first ion beam and the second ion beam have uniform energies and uniform velocity vectors and such that the first ion beam and the second ion beam overlap and collide within the collision zone; setting an energy of ions of the first ion beam and an energy of ions of the second ion beam such that a ratio of the energy of the ions of the first ion beam to the energy of the ions of the second ion beam equals an inverse ratio of respective ion masses in the head-on collisions; positively biasing a first energy recovery electrode coupled with the ion energization circuit based on a known energy of the scattered ions of the first ion beam that are scattered as a result of the collisions in the collision zone, wherein the known energy of scattered ions of the first ion beam is based on the ratio of the energy of the ions of the first ion beam to the energy of the ions of the second ion beam being equal to the inverse ratio of the respective ion masses; slowing, with the first energy recovery electrode, the scattered ions of the first ion beam; transferring kinetic energy of the slowed scattered ions of the first ion beam to the ion energization circuit; producing, responsive to the slowing and transferring, a first set of cold ions; and evacuating the first set of cold ions from the active space.
12 . The method of claim 11 , further comprising: positively biasing a second energy recovery electrode coupled with the ion energization circuit based on a known energy of the scattered ions of the second ion beam that are scattered as a result of the collisions in the collision zone, the known energy of scattered ions of the second ion beam being based on the ratio of the energy of the ions of the first ion beam to the energy of the ions of the second ion beam being equal to the inverse ratio of the respective ion masses; slowing, with the second energy recovery electrode, the scattered ions of the second ion beam; transferring kinetic energy of the slowed scattered ions of the second ion beam to the ion energization circuit to produce a second set of cold ions; and evacuating the second set of cold ions from the active space.
13 . The method of claim 12 , further comprising providing a cold ion evacuation system arranged to remove the first set of cold ions from the active space.
14 . The method of claim 11 , further comprising negatively biasing an acceleration electrode situated proximate the collision zone to accelerate ions of the first ion beam and ions of the second ion beam toward the collision zone, and to decelerate non-collided ions of the first ion beam and non-collided ions of the second ion beam as the non-collided ions pass by the collision zone.
15 . The method of claim 11 , further comprising directing, with electric fields or magnetic fields of the ion beam focusing arrangement, the first ion beam along a first looped path and directing the second ion beam along a second looped path.
16 . The method of claim 15 , wherein directing the first ion beam along the first looped path and directing the second ion beam along the second looped path comprises establishing the first looped path and the second looped path such that each of the first looped path and the second looped path resides inside and outside of the active space and carries hot ions in the active space and cold ions outside of the active space.
17 . The method of claim 15 , wherein directing the first ion beam along the first looped path and directing the second ion beam along the second looped path comprises establishing the first looped path and the second looped path such that each of the first looped path and the second looped path resides within the active space.
18 . The method of claim 11 , further comprising directing, with electric fields or magnetic fields of the ion beam focusing arrangement, the first ion beam and the second ion beam along a leaf-shaped path that includes a forward direction and a backward direction, wherein the first ion beam traveling in the forward direction is spatially separated from the first ion beam traveling in the backward direction, and wherein the second ion beam traveling in the forward direction is spatially separated from the second ion beam traveling in the backward direction.
19 . The method of claim 11 , wherein the first ion beam comprises a first species of ions, and wherein the second ion beam comprises a second species of ions that is different from the first species.
20 . The method of claim 11 , wherein positively biasing the first energy recovery electrode comprises under-biasing the first energy recovery electrode by a potential difference sufficient to reduce a quantity of scattered ions that would otherwise reverse direction of their motion and return to the collision zone.

Description

PRIOR APPLICATIONS This application is a Divisional Application of U.S. application Ser. No. 17/239,435 filed Apr. 23, 2021 which claims the benefit of U.S. Provisional Application No. 63/014,405 filed Apr. 23, 2020, and U.S. Provisional Application No. 63/085,157 filed Sep. 30, 2020, the disclosures of each of which are incorporated by reference herein. TECHNICAL FIELD Embodiments described herein relate generally to nuclear fusion and, more particularly, to apparatus and associated methodology that facilitates the recovery of energy which would otherwise be lost due to elastic scattering of ions. BACKGROUND A nuclear fusion reaction occurs when two ions of a certain kind hit each other at energies large enough for them to overcome Coulomb repulsion and approach each other at distances of the order of 10-14 m, about 10,000 times smaller than the size of an atom. Consequently, the kinetic energy required is about 10,000 times larger than typical chemical energies. The energy required is tens or hundreds keV (kilo-electron-volts), or, equivalently, hundreds or millions Kelvins on the temperature scale. The majority of fusion experiments attempt to heat plasma to the required temperatures so as to allow random ion collisions to cause fusion reactions. The high temperatures involved require confinement of the plasma, either magnetic, inertial, electrostatic, or a combination thereof, in order to protect the apparatus from the hot plasma inside. Confining and maintaining hot plasma is a formidable task that has yet to result in a controlled sustainable fusion reaction. An alternative approach is to accelerate the ions by means of electric potential, which only requires modest voltages of tens or hundreds kV. However, certain fundamental obstacles reviewed below are believed to preclude net energy gain in such a “kinematic” arrangement. The term “kinematic” in the present context refers to systems that are not in thermal equilibrium (i.e. “nonthermal”) and involve particles with energies greater than ambient temperatures. One example of why kinematic approaches do not work is usually to consider an energetic ion beam hitting a solid target. Since the fusion cross-section is so small (about 10,0002 times smaller) compared to the squared distances between the atoms in the target, an average ion will have to traverse a great many atomic layers until it has a chance of hitting a nucleus. Such an ion will be stopped at a much shorter distance by the electrons in the target. Even in configurations with no electrons present, a fast ion has a much greater chance of hitting another ion closely enough to scatter elastically but not dead-on to cause fusion. The ions that scatter elastically redistribute their kinetic energies between them, causing a cascading process that quickly leads to thermalization, i.e., the loss of the initial energy to heat. There are only two possible outcomes of thermalization: either the heat leads to the overall temperature sufficient for sustaining fusion, bringing the device to the class of plasma confining devices (not discussed here), or (ii) the temperatures are lower than fusion temperatures, in which case the energy lost to heat is unrecoverable fully due to the laws of thermodynamics, thereby precluding net energy gain. In other words, unless a very hot plasma is formed, much more energy has to be spent on accelerating the ions that are unsuccessful at fusion than any gain produced by the very few that are successful. A further example is a fusor device—the simplest device that achieves fusion reaction by means of electrostatic potentials, albeit no net positive gain has been demonstrated so far. Notably, the task of achieving fusion is not difficult; a fusor is a simple device that may be built at home or in a garage setting. Fusors are used commercially as neutron sources. The difficult, and still unsolved, task is to make a sustainable fusion reaction that can feed itself through net energy gain. Energy losses in a typical fusor device are five orders of magnitude larger than the fusion power produced. A typical fusor device does not fall into the class of kinematic fusion approaches. Rather, a fusor device is more correctly classified as an Inertial Electrostatic Confinement (IEC) device-one that still employs hot plasma, shielded from the outside apparatus by electrostatic, rather than magnetic, fields. The reason for fusors being IECs is that they share the same fundamental channel for energy thermalization. The ions in the fusor device are accelerated by electrostatic bias when they fly from the outer wall towards the center. In the center, the average kinetic energy of the ions is large enough to undergo fusion. Two cold ions accelerated towards the center from the outer wall have the same energy when they reach the center. They have a chance to hit each other and cause fusion, but they also have a much greater chance to scatter elastically and re-distribute their energy between