In this paper a simulation approach is presented, that allows for virtually investigating the performance of automotive radar systems regarding different system parameters. This is achieved by combining dedicated simulation models for the radar transmitter and receiver with a deterministic propagation simulator based on ray tracing. This approach is in particular suitable for investigating the capabilities of beamforming algorithms in radar systems with multiple antenna receivers. The configuration of the developed tool is explained in detail and the performance of different array configurations for classic digital beamforming and the MUSIC algorithm is evaluated.