In this study, an ice accretion method aimed at ice crystal icing in turbofan engines is developed and demonstrated for glaciated as well as mixed-phase icing conditions. The particle trajectories are computed by an Eulerian trajectory method. The effects of heat transfer and phase change on the particle trajectory and on the impact at the icing surface are taken into account. The computation of the evolution of the ice layer includes the contributions of ice and liquid water for mixed-phase conditions as well as the effects of erosion caused by ice crystals. Verification and validation benchmarks are carried out for a NACA 0012 airfoil and a streamlined shape with a curved cylindrical nose. It is shown that the ice thickness and shape are predicted accurately by the proposed method.