I understand that you would like to know if simulating a closed loop system is possible in Simscape. Yes, it is possible. You can go through the following examples that showcase the use of closed loops in Simscape Physical Modelling:
- Change Model into Closed-Loop System https://www.mathworks.com/help/simscape/ug/change-model-into-closed-loop-system.html
- Model Thermal Effects in a Closed-Loop System https://www.mathworks.com/help/simscape/ug/model-thermal-effects-in-a-closed-loop-system.html
Hope this helps in resolving your query!