MC-1 Generator Research Articles

Reproducible Multimegagauss Fields—History of Ideas and Their Realization

It is already several tens of years to a cascade magnetocumulative (MC-1) generator of reproducible magnetic fields of multimegagauss range—a well-known device in megagauss physics. Due to several reasons, it seems to be necessary to recall the history of creation of this physical device, for which capabilities are still unique. First, this could be interesting; second, there is a desire to remind and appreciate contribution and services of the MC-1 generator designers who have left the business; third, this story could help to understand an operation principle and possibilities of the generator to new generation of the megagauss community, convince it that this source of extreme conditions is exceptionally convenient and useful research tool. These ideas suggesting, developing, and examination were carried out in close collaboration with Pavlovskii and Kolokolchikov.

Numerical Simulation of MC-1 Cascade Generator for Generating 20-MG-Range Magnetic Field

At the first stage of work related to the production of a generator for generating 20-MG-range magnetic field special attention was paid to learning, updating, and testing magnetocumulative (MC) MC-1 generator numerical models based on MASTER Pro software package aiming to use these models for choosing the most promising generator design. The functionality of a generator and variety of its applications imposes two significant restrictions on a generator HE full mass and the size of the maximum magnetic field volume (basically, diameter). Based on the design-theoretical work, we proposed a design and determined initial parameters for MC-1-generator with the maximum magnetic field >20 MG in the volume with a diameter of no <;5 mm and HE mass <;50 kg.

Research in ultrahigh magnetic field physics

The history of the achievements of the All-Russian Research Institute of Experimental Physics (VNIIEF in Russ. abbr. )i n the field of ultrahigh magnetic field (UHMF) generation and applications in fundamental physical studies begins in 1952, when Andrey D Sakharov put forward the idea of magnetic cumulation as one of the possible methods for achieving a controlled thermonuclear reaction [1]. He also proposed two types of magnetocumulative generators of UHMFs (MC-1) and energy (MC-2) [1, 2]. In the first of them, a special device produces the initial axial magnetic field flux in the cavity of a cylindrical metal shell (liner). A converging detonation wave is initiated in a circular explosive charge surrounding the liner so that it arrives at the external boundary of the liner at the instant of time when the initial magnetic field in the liner achieves a maximum. Under the action of pressure of the detonation products, the liner collapses to the center, compressing the initial magnetic flux. If the compression is rapid enough,the magnetic flux inthe cavity is preserved, and themagnetic fieldstrengthonthelineraxisincreasesinversely proportionally to the squared radius of the liner, achieving a few megagausses. The chemical energy of the explosive is transformed into the magnetic field energy through the kinetic energy of the liner. Extensive attempts made in many countries to reproduce UHMFs by the explosive compression of a magnetic flux revealed unexplainable difficulties in obtaining magnetic fields exceeding 3 MG, which resulted in the termination of work in this field. 2. MC-1 cascade generator A group of researchers at VNIIEF headed by A I Pavlovskii proposed and realized a number of concepts supplementing and developing the magnetic cumulation idea and solved the problem of the reproducible generation of UHMFs. First, it was proposed to make the shells of the MC-1 generator from a material with a controllable electrical conduction. Such a material in the initial state is either completely nonconducting or conducts current only in one direction. At the required instant, a shock wave is passed through the material, making it conducting in all directions. For example, such a material can be produced from closely packed parallel isolated copper wires glued with an epoxy compound. Second, unique solenoids of the initial magnetic field in

On one possibility of cascade MC-1 generator final-magnetic field increasing

The problem of magnetic flux compression by a thin-walled metal (tungsten) cylinder imploded with the cascade magnetocumulative MC-1 generator was numerically considered. The initial magnetic field diffuses into the cylinder during the MC-1 generator powering-time interval and the slow phase of magnetic flux compression by the MC-1 generator. Then the cylinder rapidly gathers a velocity approximately 1.5 times more than the velocity of the MC-1 generator liner and amplifies the magnetic field on the axis up to about 20 MG. The optimum ratio of cylinder parameters and MC-1 generator operation regime was determined using a numerical one-dimensional device model in order to obtain maximum final magnetic field in a small volume, but still suitable for applications with a diameter of about 3 mm.