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System Modeling


The purpose of this work is to model the IWESS components (energy input systems, ventilation unit, cooling and heating devices):

  • to estimate their annual performance
  • to assist and optimize their design
  • to determine their most efficient operation

and then, the overall IWESS system:

  •  to determine its effectiveness, energy efficiency and cost
  •  to estimate the energy (thermal and electrical) consumed by the IW and the energy exported to the grid   

Mathematical models have been created in TRNSYS (TRaNsient energy SYstem Simulation). This simulation program is developed by the SEL, CSTB, TESS and TRANSSOLAR. TRNSYS supports detailed simulations of multi zone buildings and their energy supply equipment, especially solar systems. Exercise of the TRNSYS simulation tool enables the search for an optimal system configuration, equipment design and operational mode.    
Simulations have been or are actually performed for the following devices/systems:    

  • Solar cooling and heating system (with fan coils and ventilation unit)
  • Biodiesel engine generator with heat recovery
  • Fan coils and controls 
  • Radiant heating and cooling
  • Natural ventilation

The time table for the IWESS modeling is shown below:  


Previous projects:
- Performance modeling of the solar thermal system (calculates annual energy performance / assists the design / optimizes the system)
- Performance modeling of the natural ventilation in terms of cooling and ventilation requirements

Current projects:
- Impact of the control strategy of the fan coils on the cooling and heating requirements and on the thermal comfort
- Performance modeling of the biodiesel engine generator with heat recovery
- Extension of the natural ventilation model (improvement of the window / vent opening control strategies)
- Comparison between traditional single duct VAV air and radiant H&C systems (in terms of energy consumption and thermal comfort)