Change of ultrasonic propagation velocity in an MR fluid under AC magnetic fields

Article type: Research Article

Authors: Fukumoto, Takashi^a | Tanaka, Yuya^a | Sawada, Tatsuo^a;

Affiliations: [a] Department of Mechanical Engineering, Keio University, Kohoku-ku, Yokohama, Japan

Correspondence: [*] Corresponding author: Tatsuo Sawada, Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan. E-mail: sawada@mech.keio.ac.jp

Abstract: This paper reports the experimental studies on a magneto-rheological (MR) fluid under AC magnetic fields. Magnetic clusters in the MR fluid are formed along the magnetic fields. The ultrasonic propagation velocity changes owing to the presence of clustering structures in the MR fluid. We investigated clustering structures by measuring this change in the ultrasonic propagation velocity. The results indicate that magnetic clusters in the MR fluid depend on the elapsed time, intensity, frequency, and angle of the AC magnetic fields.

Keywords: Magnetic fluid, ultrasonic wave, AC magnetic field, anisotropy

DOI: 10.3233/JAE-171174

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 59, no. 1, pp. 341-347, 2019