System Design and Optimization of a Miniaturized Ion Mobility Spectrometer Using Finite-Element Analysis

Ion mobility spectrometry (IMS) is a widely used method for detecting low ppb-level concentrations of hazardous compounds, such as chemical warfare agents, explosives, and pollutants in air. Simple instrumentation combined with high sensitivity and high selectivity are major advantages of this technique. We are currently developing a miniaturized low-cost IMS that can be used in various applications, where fast detection of chemical compounds at low ppb-levels is required and space is limited. A numerical model based on finite-element analysis has been developed for rapid system design and optimization with respect to physical and economic constraints. All significant physical effects on the ion transport in an IMS are considered within the simulation, such as diffusion, coulomb repulsion, electric fields and gas flows. This model is a powerful tool for developing, studying, and optimizing miscellaneous types of IMS.