This webinar explains how Flownex can be used to model both process systems and control systems for controller tuning and optimization. It introduces common PID tuning methods and demonstrates how process step testing can be used to calculate controller settings using the Cohen-Coon tuning approach. A tank level control example shows how Flownex performs transient simulations, exports results for analysis, and validates controller performance under changing operating conditions. The presentation also highlights advanced applications such as compressed air network control and shutdown control strategies for a supercritical Brayton cycle. Overall, it demonstrates how simulation-based controller tuning can improve plant performance, reduce commissioning time, and support the development of safer and more efficient control philosophies.