Desiccant wheels for air humidification: An experimental and numerical analysis

Abstract In this work the use of a desiccant wheel for air humidification is investigated through a numerical and experimental approach. In the proposed humidification system, water vapour is adsorbed from outdoor environment and it is released directly to the air stream supplied to the building. Such a system can be an interesting alternative to steam humidifiers in hospitals or, more generally, in applications where air contamination is a critical issue and therefore adiabatic humidifiers are not allowed. Performance of the proposed system is deeply investigated and optimal values of desiccant wheel configuration parameters are discussed. It is shown that in the investigated conditions, which are representative of Southern Europe winter climate, the system can properly match the latent load of the building. Finally, power consumption referred to the primary source of the proposed humidification system is compared to the one of steam humidifiers. The present analysis is carried out through experimental tests of a desiccant wheel in winter humidification conditions and through a phenomenological model of the device, based on heat and mass transfer equations.

[1]  K. Sing.  Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity (Recommendations 1984) , 1985 .

[2]  Carlo Roselli,et al.  Dynamic performance assessment of a micro-trigeneration system with a desiccant-based air handling unit in Southern Italy climatic conditions , 2014 .

[3]  Stefano De Antonellis,et al.  Desiccant wheels effectiveness parameters: Correlations based on experimental data , 2015 .

[4]  Yong Li,et al.  Experimental investigation and theoretical analysis of solar heating and humidification system with desiccant rotor , 2011 .

[5]  A. E. Kabeel,et al.  Performance of desiccant air conditioning system with geothermal energy under different climatic conditions , 2014 .

[6]  Yunfei Dai,et al.  Numerical analysis and optimization of a solar hybrid one-rotor two-stage desiccant cooling and heating system , 2014 .

[7]  Stefano De Antonellis,et al.  Simulation, performance analysis and optimization of desiccant wheels , 2010 .

[8]  E. Elgendy,et al.  Performance enhancement of a desiccant evaporative cooling system using direct/indirect evaporative cooler , 2015 .

[9]  Ciro Aprea,et al.  The application of a desiccant wheel to increase the energetic performances of a transcritical cycle , 2015 .

[10]  Song Du,et al.  Feasibility and economic analysis of solid desiccant wheel used for dehumidification and preheating in blast furnace: A case study of steel plant, Nanjing, China , 2015 .

[11]  José Manuel Cejudo López,et al.  Influence of the desiccant wheel effectiveness method approaches, with fix and variable effectiveness parameters, on the performance results of an airport air-conditioning system , 2015 .

[12]  Stefano De Antonellis,et al.  Experimental analysis and practical effectiveness correlations of enthalpy wheels , 2014 .

[13]  Stefano De Antonellis,et al.  The Effect of Inlet Velocity and Unbalanced Flows on Optimal Working Conditions of Silica Gel Desiccant Wheels , 2014 .

[14]  K. F. Fong,et al.  Solar hybrid cooling system for high-tech offices in subtropical climate – Radiant cooling by absorption refrigeration and desiccant dehumidification , 2011 .

[15]  Stefano De Antonellis,et al.  Simulation and energy efficiency analysis of desiccant wheel systems for drying processes , 2012 .

[16]  Ye Yao,et al.  Energy consumption analysis on a dedicated outdoor air system with rotary desiccant wheel , 2007, Energy.

[17]  Robert J. Moffat,et al.  Describing the Uncertainties in Experimental Results , 1988 .

[18]  Ge Zhang,et al.  Simulation and energy saving analysis of high temperature heat pump coupling to desiccant wheel air conditioning system , 2015 .

[19]  Mario Motta,et al.  Grey-box modelling and in situ experimental identification of desiccant rotors , 2013 .

[20]  Refrigerating.  ASHRAE handbook and product directory /published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc , 1977 .

[21]  Yanjun Dai,et al.  Study of a solar powered solid adsorption–desiccant cooling system used for grain storage , 2002 .

[22]  Rajnish K. Calay,et al.  Experimental study of an energy efficient hybrid system for surface drying , 2011 .