  We propose the application of the arbitrary Lagrangian-Eulerian (ALE)
technique to a compressible lattice Boltzmann model for the simulation of
moving boundary problems on unstructured meshes. To that end, the kinetic
equations are mapped from a moving physical domain into a fixed computational
domain. The resulting equations in the computational domain are then
numerically solved using the second-order accurate finite element
reconstruction on an unstructured mesh. It is shown that the problem regarding
the geometric conservation law (GCL), which needs a special treatment in the
ALE Navier-Stokes solvers, does not appear here and the model satisfies the GCL
exactly. The model is validated with sets of simulations including uniform flow
preservation and compressible flow past airfoil with plunging and pitching
motions at different Mach numbers. It is demonstrated that the results are in
good agreement with the experimental and other available numerical results in
the literature. Finally, in order to show the capability of the proposed solver
in simulating high-speed flows, transonic flow over pitching airfoil is
investigated. It is shown that the proposed model is able to capture the
complex characteristics of this flow which involves multiple weak shock waves
interacting with the boundary and shear layers.
