Study on single bubble in acceleration sensor with magnetic fluid

Abstract

Problems caused by bubble are always inevitable in acceleration sensor with magnetic fluid (ASMF) and influence the performance of the sensor. In this paper, the behavior of single bubble in ASMF is investigated. The relationship between output voltage (Uo) and acceleration (a) of the sensor without bubble is studied theoretically, and it can be clearly found that the linear law is obeyed approximately. Moreover, the formula of total force of the single bubble in ASMF is derived. To analyze the force on the bubble, simulation analysis is utilized by emulating the normal magnetic field strength on the boundary of the bubble. Finally, experiments are presented with different volume fractions of bubble (ranging from 0 to 0.135). Experimental results show that Uo is linear to a when there is no bubble or the bubble is relatively small. It also shows that bubble greatly influences the linearity of the sensor. The difference between experimental results and the theoretical analysis is less than 6.25%.