Software architecture is high-level software design, dealing with the structure and organization of software systems. A software architecture is defined in terms of computational components and interactions among those components. Architecture Description Languages (ADLs) represent architecture-level software designs. Different ADLs often have different intents; e.g., Rapide supports architecture simulation and Acme is intended to be both an ADL and an ADL interchange format. Experimental applications of two ADLs were conducted to determine the effectiveness of ADLs for architecture-level analysis of simulation systems; one of them is reported. Acme was used to model the architecture of ModSAF and to analyze its run-time performance. The model was used to analyze execution time at the component and federate levels and to estimate the maximum number of internal and external simulation entities that could be supported by the ModSAF architecture. The experiment showed that ADLs could model important features of simulation system architectures.