Out of curosity, I'd like to know how to model a steam boiler with two horizontal cylinders? I'd like to create a model with multipule flues and eventually super heating the steam. All I need as an example of a simple model. Thanks.
I recommend you to start from the physical concept (thermodynamic cycle ideally) using half heat exchanger and functional components from the TPF library. As an example, there is a very nice demo on heat pump modeling available since rev15 available here.
After that you can replace the half heat exchanger by a more detailled approach.
Keep me informed if you face any issue on this modeling.