The blast waves generated by the explosion of a bomb or the violent thrust of a missile launch would damage the personnel and facilities. Understanding the blast effects and behaviors is very important in minimizing or even avoiding their damages. Due to the lack of experimental facility, the numerical simulation method, CFD, was used to study the behaviors of blast waves. Validations of the numerical model developed in this study against test data obtained from a symmetric shock tube and a two-dimensional wedge were done first. Subsequently, fundamental studies in interaction, propagation, and reflection of blast waves were carried out to investigate the behaviors the blast waves. Furthermore, the scheme developed in this study was used to simulate the more complex geometries and the moving body. The computational application of dynamic meshing system provided more realistic conditions. In summary, this thesis provides the research tools and in-depth understanding of the effects associated with the blast waves to the industry for designing and enhancing the materials to prevent the potential disasters caused by the explosions and blast waves.