Simulation models at CTS are written in-house using commercially available computer software and have been successfully used to predict system and component performances. Dynamic and steady-state system response, including such information as cooling capacity and energy efficiency (COP) has typically matched to the experimental data with an accuracy of 5% or better. The computational models are used in design as well as analysis and optimization of the elements under examination. Typical simulation models are modular in nature, allowing fundamental correlations to be easily included. Appropriate component models can then be seamlessly combined to predict full system performance. Many of these simulation models have been validated and subsequently refined over a wide range of operating conditions in the course of multiple research projects.