Numerical Simulation of Ion Drift within Ion Mobility Spectrometers in High Peclet Conditions using FEM Techniques

The goal of this paper is to model and simulate the transport of ions through a miniaturised drift tube of ion mobility spectrometer (IMS). In the first part of this work we test and compare three numerical methods to solve the transient diffusion-advection equation in high Peclet conditions. These methods are the following: Streamline upwind Petrov Galerkin (SUPG), the modified-PDE (MPDE) and the finite calculus method (FIC). In the second part we use the last two numerical methods to study ion transport in a one-dimensional IMS model. Ion peak broadening effects, namely coulombic repulsion, diffusion, transport of two ionic species, have been explored for different initial conditions.