Kazunari Ikuta

Electromagnetic Acceleration of Macroparticles to Hypervelocities in Axisymmetric Geometry

The electromagnetic acceleration of macroparticles to hypervelocities in axisymmetric geometry is considered and a new type of plasma impulse accelerator with cylindrical electrodes is proposed. The accelerator consists of a series of cylinders with their axes of symmetry on a straight line. When it is ready to be propelled, the projectile should be introduced into the second electrode together with the ablator. The projectile is propelled by the J×B force of the plasma current along the surface of the ablator, located behind the projectile.

Ohmic Ignition of Alcohol-Ammonium Nitrate Mixture for Hot Light Gas Generation

The theoretical considerations of the ohmic ignition of an alcohol-ammonium nitrate mixture for the generation of hot light gas are described in detail along with a suggested design for an accelerator.

Dynamics of the Sun-Mill

The dynamic behavior of the sun-mill is analysed in detail and the experimental results for the output power of the ultimate sun-mill are also given.

New Lens System Using Toroidal Magnetic Field for Intense Ion Beam

The use of toroidal magnetic field as a lens system is proposed for producing intense ion beam. The characteristics of the lens system are obtained both analytically and numerically. Some examples of ray-trajectories are presented for different focal lengths. The system is applicable to neutral beam injection heating and micro-pellet implosion for nuclear fusion, and to the other fields such as ion beam X-ray lasers.

Motion of Fluid Driven by Electro-Thermally Ablated Gas Pressure

We study the motion of fluid driven by electro-thermally ablated gas pressure in a cavity with a single exhauster. A possibility of jet propulsion engine for steamers is also discussed as an application of the fluid motion.

Direct Energy Input to Compressor for Inertial Confinement Fusion

An effective method for driving ICF pellet compression is proposed where neither laser beam nor charged particle beam is necessary but rather high electric pulse power is directly input into a vacant space between a shell tamper and its enclosed pellet. Electrons emitted from the pellet surface produce a dense, hot plasma on the inner side of the tamper. Photons and particles of the plasma irradiate the pellet surface and give rise to an effective ablation-driven compression. This direct energy input to compressor (DEIC) can be done efficiently and makes it easier to picture an ICF reactor.

Hypervelocity Accelerators with Electro-Thermo-Chemical Reaction

A novel kind of electro-thermo-chemical (ETC) launcher for the acceleration of multikilogram-size projectiles to hypervelocity is proposed. The novel launcher concept utilizes the hot hydrogen gas generated by the chemical interaction between water and aluminum in order to accelerate the projectiles to a thermal velocity close to that of the light gas. This interaction is triggered by the Joule heating of the aluminum wire in water. Two possible designs for the accelerator concept are considered in detail. Further acceleration of the projectile near the muzzle is also discussed.

Behavior of Liquid Fuse in a Non-Destructive Opening Switch

This paper proposes the use of an exploding liquid fuse in a liquid insulator, e.g. water, as a possible non-destructive opening switch. The opening time was culculated analytically with a simple model for the explosion of the liquid fuse. This analytical model was also checked by a numerical computation.

Conical liner implosion as a projectile injector for mass drivers

An electro-magnetic method for injecting a projecting a projectile into a mass driver using a conical liner in proposed.

Compact Toroids with Rotating Halo-the Spintor

Stability analysis to tilting mode is performed for a type of compact toroids (CT) spinning about its axis of symmetry and a new method of giving CT a spin about the axis is proposed.