TRNFlow – AIRFLOW SIMULATION IN BUILDINGS

TRNSYS thermal mutlizone building model, type 56, requires air flows between zones as input values. However, in natural ventilation systems these depend on the wind pressures and the inside and outside temperatures. To account for this situation, a coupling with an air flow model is absolutely necessary.

TRNFLOW integrates the multi-zone air flow model COMIS into the type 56. An internal solver, optimized for this task,  iterates in each time step between the two models until their solutions are consistent. The existing GUI TRNBuild was extended in such a way that data for the air flow model can be entered. Thus a user-friendly handling of the coupling is assured. With TRNFLOW, a immense step forward has been made for building simulation with TRNSYS.

Advantages of TRNFlow:

• TRNFLOW is a tool which allows an easy calculation of natural ventilation, passive night cooling, double facades and exhaust air shafts quite fast.
• No new input file structure or user interface has to be learned. Simply the known user-friendly TRNBuild has been expanded. Due to the full integration the required input data is greatly reduced and less error-prone.
• The newly-developed internal solver is featured with high stability. Due to the integrated automatically optimization of convergence the user is no longer bothered with numerical questions.