  Dynamics of a droplet in oscillatory and pulsating flows of a Newtonian fluid
in a microchannel has been studied numerically. The effects of oscillation
frequency, surface tension, and channel flow rate have been explored by
simulating the drop within a microchannel. These types of flows introduce new
equilibrium positions for the drop compared to steady flows with similar
conditions. The simulation results are very sensitive to the grid resolution
due to the unsteady behavior of the base flow. Therefore, a set of fine grids
have been used in this study to capture the physics of this problem more
accurately. However, these fine grids make the computations significantly
expensive. Therefore, a Multi Fidelity Gaussian processes method with two
levels of fidelity has been used to predict the results of the remaining
fine-grid simulations along with their uncertainties based on their
correlations with those of the coarse-grid cases over a wide range of input
parameters.
