Calculation of the Effectiveness of a Dehumidifier and Integration of a New Model of a Desiccant Wheel into TRNSYS

Rotating wheel dehumidification is a relatively new air cooling technique used in air conditioning, insufficiently researched and applied in practice.The system's effectiveness depends significantly on the desiccant wheel's properties and the moist air operating parameters.Modern software and simulations with defined inputs, can predict process air conditions required for air conditioning as long as each component characteristics of the system are known.In this work, an existing component in TRNSYS was used to simulate the desiccant wheel operation, which for stationary operating conditions and predefined efficiency aligns well with experiments.However, for a time-varying process, significant deviations of the results are observed, i.e. when the entered wheel efficiency does not correspond to every condition of the air entering the wheel.Considering that TRNSYS requires the definition of the desiccant wheel's efficiency before simulation start, treating them as fixed parameters, with the existing model component located in its database, it is impossible to carry out the simulation for time-varying conditions with satisfactory accuracy.A modified desiccant wheel model was developed and integrated into TRNSYS, which allows changing the functions of potential F1 and F2 and efficiencies εF1 and εF2 during simulations, for time-varying parameters of the humid air inlet state.