We report the results of a Dissipative Particle Dynamics (DPD) study on deformable droplet migration in a narrow microchannel at finite Reynolds numbers. We find that droplet migrates to a position between that of the well-known Segre and Silberberg position for that of a rigid particle due to inertial lift forces, and those reported for deformable droplets at zero Reynolds number by Chan and Leal. The ultimate, steady-state, position in our simulations is dependent upon the capillary number, the Reynolds number, the relative viscosities of the droplet and suspending fluid, and to some extent on the ratio of droplet size to channel height. We discuss the relevant dimensionless groups that affect the droplet position, the effects of inertia and inter-particle/inter-wall interactions, and establish connections to related previous studies in the literature. We also assess the conditions needed for convergence of the DPD results to the continuum limit in which the discreteness of the particles in the DPD simulations and size of the periodic simulation domain become negligible. The study not only improves our understanding of migration phenomena in microfluidic geometries, but also provides an assessment of the DPD method as a tool for predicting such phenomena in realistic experiments.
