Study offlow electrification in pulsating flow

点击翻译按钮获取中文摘要

Measurement of electrification in transient change of velocityThe current detected from the metal wall rose to a peak value at the beginning of flow, then exponentially decreased until it leveled off with time, approaching a constant value. The smaller the acceleration of velocity was, the smaller the peak value of current was. This behavior of the current presumably indicates that relaxation of charge depends on the time, though generation of charge depends not on the time but on the gradient of velocity on the interface.Measurement of electrification in pulsating oil flowPulsating oil flows were let pass through a metal mesh and a metal plate with eight holes. The current fluctuates at the same frequency as that of the flow rate. The relationship between the current and the flow rate in an oil flow pulsating at lower frequencies can be approximated by that in a steady flow. However, it is no more the case for higher frequencies. The delay times of the current behind the flow rate take almost the same value for different frequencies in the present experiment.