Research Topics
1. Fundamentals and applications of particle electrification
The contact electrification of particles is a fundamental phenomenon that occurs during powder handling processes, and the electrostatic forces acting on particles significantly affect particle behavior; thus, the control of particle charging is important for powder handling operations. In fact, applications for charged particles have been widely developed, e.g., electro-photography, dry powder coating, and electrostatic separation. As operations such as dispersion, agglomeration, and particle transport can be remotely controlled by electrostatic forces, further technological innovations are expected in this direction. To realize the full potential of the existing technology, an in-depth understanding of particle charging, charge distribution control, particle movement control, and relevant online measurement techniques is needed.
1. Study on triboelectric charging of particles in gas–solid two phase flow.
2. Analysis of triboelectric charging of particles in a vibration field.
3. Control of the movement of charged fine particles in electric fields with spatial and temporal variation.
4. Development of a particle charge controller using centrifugal force and its application.
5. Development of a high-accuracy measurement system for charge distribution of fine particles.
2. Evaluation of adhesion and flowability of particles
Particle–particle and particle–wall interaction forces are important factors that directly affect powder handling, and appropriate methods need to be developed for measuring the adhesive property between primary particles or agglomerated particles and for evaluating the flowability of particles.
1. Analysis of adhesive strength distributions of particles subjected to various external forces.
2. Analysis of flowability profiles.
3. Handling of submicron- and nanoparticles
The demand for submicron- and nanoparticles is growing on account of the need to produce highly functional products. However, their adhesiveness increases with decreasing particle diameter, and as a result, powder handling becomes more complex for small particle diameters. In particular, for particles having a diameter of less than 1 m, the complications due to adhesiveness are pronounced and it is therefore imperative to develop new techniques as well as analyze particle behavior for overcoming these issues.
1. Control of the movement of fine particles using multiple vibration modes.
2. Development of a novel fluidized bed system using vibration convection mechanism.
3. Development of micro-feeding of nano-particles based on vibration shear flow.
4. Development of a pneumatic transport system for nanoparticles.