open access

https://hdl.handle.net/2115/47196

Direct measurement of fluid force on a particle in liquid by telemetry system

英語

Sedimentation

2011-10

Elsevier

International Journal of Multiphase Flow

37(8)

898-905

For real-time measurement of the fluid force acting on a particle which moves freely in liquid, we have made a "sensor particle" with a built-in wireless sensor. The sensor particle contains a 3-axis acceleration sensor, 3-axis magnetometer, microcomputer, wireless module and cells. The MEMS acceleration sensor detects the gravitational acceleration in addition to the dynamic acceleration of particle. In order to remove the gravity from acceleration signals, we applied the external magnetic field which is oriented in the same direction as the gravity field. The 3-axis magnetometer detects the direction of external magnetic field and consequently we can remove gravitational acceleration from the sensor signals with arbitrary attitude of particle. A preliminary experiment was performed for checking the accuracy of the measurement system. Firstly we measured the force acting on a settling particle toward a solid wall in liquid. The obtained signals of acceleration (force divided by mass) agrees well with the theoretical prediction of particle motion in liquid for each instant of time. The sensor particle also detects the lubrication force which is exerted on particle for a very short time when it comes close to the wall. Moreover, we applied our system to the gravitational settling of the particle assemblage and detected the fluid force acting on a particle in multi-particle system.

学術雑誌論文

Accepted Manuscript

0301-9322