Desiccant Dehumidification Coupled with Radiant Cooling System in Hot And Humid Areas

Different Air Conditioning systems were investigated and developed over the past few years targeting to improve indoor air quality, thermal comfort, andoverall system energy efficiency. Radiant cooling systems are gaining popularity, where they rely on radiant heat transfer to cool the space and achieve indoordesign conditions through a hydronic piping system. Compared to traditional air systems, radiant cooling scheme presents an energy-efficient alternativeaddressing sensible space load. Dedicated Outdoor Air Systems (DOAS) coupled with radiant systems, improve indoor air quality, and account for latentspace load. Outdoor air contribution to building load is a major energy concern; and presented in this work, the adoption of Desiccant dehumidification forDOAS ventilation coupled with a radiant cooling system to reduce building energy demands.Utilizing desiccant dehumidification is an application that reduces the energy demand in a project. The use of a radiant cooling system for highly occupiedspaces is limited by the capacity of the DOAS to remove the latent space loads. The increased DOAS airflow might hinder the overall savings achievedthrough the use of radiant cooling system. The investigated configuration of 100% outside air desiccant dehumidification wheel with a cooling coil andrecovery wheel, increases the latent capacity of the system while reducing the airflow necessary for space latent load removal.The presented configuration reduces the apparatus supply air dew point without lowering the leaving cooling coil dry bulb temperature. As presented, the airmoisture water content downstream the cooling coil is reduced by the desiccant wheel effect using the proposed configuration. The same wheel is regeneratedby the apparatus entering exhaust air stream. The adopted arrangement supplies dehumidified outside air that addresses latent space load at optimalflowrates, resulting in outside air cooling load reduction. The presented system achieves optimized energy savings up to 39% compared to the ASHRAE90.1 baseline VAV system.