  The performance of a single or the collection of microswimmers strongly
depends on the hydrodynamic coupling among their constituents and themselves.
We present a numerical study for a single and a pair of microswimmers based on
lattice Boltzmann method (LBM) simulations. Our numerical algorithm consists of
two separable parts. Lagrange polynomials provide a discretization of the
microswimmers and the lattice Boltzmann method captures the dynamics of the
surrounding fluid. The two components couple via an immersed boundary method.
We present data for a single swimmer system and our data also show the onset of
collective effects and, in particular, an overall velocity increment of
clusters of swimmers.
