Particle Technology

Academic Staff


Shuji MATSUSAKAProfessor (Graduate School of Engineering)

Research Topics

  1. Study on particle deposition and reentrainment.
  2. Measurement and analysis of the charge distribution of aerosol particles.
  3. Study on impact electrification of particles.
  4. Fine classification of industrial sub-micron particles.


Bldg. ROHM Plaza, Katsura Campus
TEL: +81-75-383-3054
FAX: +81-75-383-3054

Introduction to Research

Research in this chair is focused on the analysis of phenomena in particle handling processes and on the development of the methods for the rational handling of them. Particles are widely used in various fields; however, the particle behavior in different conditions or in multiple fields is very complicated; thus, a full understanding is needed from the viewpoint of the effective application of fine particles and for environmental protection. In particular, for dry powder systems, 1) analysis of dynamic behavior of particles, 2) control of particle adhesion, 3) evaluation of the total property including the effect of static electricity are required to be studied. Current research topics are as follows:

1. Electrification of particles

Tribo-electrification of particles is a fundamental phenomenon occurring in powder handling processes, and the accumulated charge or electrostatic force acting on the particles significantly affects the operation. However, applications using charged particles have been widely developed, e.g. electro-photography, dry powder coating, and electrostatic separation. Since dispersion, agglomeration, and transport of charged particles can be remotely controlled using electrostatic force, the development of new applications is expected. To realize it, a correct understanding of the particle charging, the control of charge distribution, the control of particle movement, and relevant online measurement techniques are required.

(1) Clarification of the mechanism of particle charging in a steady electric field.
(2) Control of the movement of charged particles under an electric field with spatial and temporal variation.
(3) Analysis of the simultaneous transfer of mass and charge in a particle bed.
(4) Development of a high-accuracy charge distribution measurement system for fine particles.

Fig. 1. Simultaneous measurement of charge and particle diameter distribution.

2. Evaluation of Adhesive property and flowability of particles

Particle-particle, particle-wall interactions are important factors directly affecting powder handling, and it is required to develop appropriate methods for measuring adhesive property of primary particles and aggregate particles, and for evaluating the flowability of particles.

(1) Analysis of adhesive strength distributions in various complex fields.
(2) Analysis of flowability profiles.

3. Mechanical handling of nano and submicron particles

The demand for functional fine particles is increasing every year. Particle adhesion is larger with reducing particle diameter and powder handling becomes much difficult. In particular, for small particles less than 1 μm in diameter, the situation is serious, and it is urgent to develop new techniques, as well as to analyze of the particle behavior.

(1) Development of micro-feeder for nano particles using a vibration shear field.
(2) Development of a system for particle dispersion using an ultrasonic vibration and airflow.
(3) Construction of a pneumatic transport system for nano particles.

Fig. 2. Control of the movement of charged fine particles under an electric field with spatial and temporal variation; (a) linear type; (b) cloud type.

Fig. 3. Micro-feeding of nano particles based on a novel vibration shear flow method.