Nondimensionalized Parametric Modeling of Fringing Electric-Field Sensors

Fringing electric field (FEF) sensors are widely used for noninvasive measurement of material properties, such as porosity, viscosity, temperature, hardness, and degree of cure. They are also used to detect the presence of a material or estimate the concentration of a material within the test environment. No generic analytical models exist for FEF sensors. Optimization of FEF sensor design often involves complex and time-consuming finite element simulations. This paper presents a nondimensionalized parametric model to improve the design process. The effects of design parameters, such as sensor geometry and substrate material, are quantified in the model. The model parameters are determined from a three-dimensional surface fit of finite element simulation results for the most common type of sensor geometry. The variables in the model are nondimensionalized, which makes the model applicable to a wider range of sensor designs