Modeling and measurement of microfabricated corona discharge structures

This paper reports on corona discharge needle-to-plane configurations to act as ionizers for airborne particulate analysis applications. Three electrode configurations are explored with the objective of obtaining a high electric field strength to maximize the probability that all incoming particles are ionized. The hybrid FE-Trefftz method, which has been developed to combine the best of both finite elements (FE) and boundary elements (BE), is used to calculate the electric fields of our ionizers. According to the simulations using the electrostatic analysis of ANSYS™, the rounded needle-to-one-plane and needle-to-two-plane are found to produce higher electric fields, when compared to the needle-to-three-plane. Our modeling results are verified and validated by the maximum electric fields, which are governed by the Paschen’s law, and the experimental results, which are based on our measurements and the previously published report respectively. The Townsend current-voltage approximations of corona currents are also formulated based on our measurements to find the closed forms of the objective functions for optimization and design in future.