A Nonlinear Dielectric Measurement Method for the Study of Complex Liquids

Abstract

A measurement system for the study of nonlinear dielectric effect (NDE) of complex liquids is constructed. The method is based on the determination of a change in frequency of an LC oscillator. The fluid is contained in a dielectric cell, which is the capacitive component of the oscillator. A rectangular electric pulse with variable amplitude and width is applied to the liquid, and the frequency of the oscillator is continuously sampled under the duration of the pulse with a modulation domain analyzer. The magnitude of NDE for diethyl ether and carbon tetrachloride was measured with the apparatus and compared to corresponding reference data. The NDE value of silicone oil used as a carrier liquid of electrorheological (ER) fluids was also determined.