A pressurized vessel-pipe-safety valve (PVPSV) system is a common configuration for many energy management systems, and a better understanding of their dynamics is helpful for system design and optimization. In this paper, a method for high-fidelity computational fluid dynamics (CFD) modeling is presented, which can be used to predict dynamic responses of PVPSV systems. For modeling, regions from the vessel outlet to the safety valve exit flange are modeled using a CFD approach; the pressure vessel is set as the boundary and the movement of the valve disk is represented by a one-dimensional (1D) rigid body motion model. Simulations are performed, and both stable and unstable operation are investigated. To establish accuracy, an experimental test rig is designed and constructed to measure the motion of the valve disk and the pressures at different system locations. Comparisons are performed for different dynamic modes and good agreement is obtained, supporting the accuracy of the high-fidelity model in reproducing the dynamic response of PVPSV systems. With the developed model, influences of other variables, such as piping length and safety valve configurations, can also be evaluated. The method presented in this paper can also be used to develop CFD models for other similar systems and should facilitate system design and optimization.