International Scientific Journal

Thermal Science - Online First

online first only

Experimental and model based performance investigation of a solid desiccant wheel dehumidifier in subtropical climate

This paper presents real time performance analysis of a silica gel based desiccant wheel dehumidifier. Thermodynamic model is also validated through comparison under a wide range of operating conditions for subtropical climate conditions. Initially, a mathematical model is developed by using various set of equations for desiccant wheel dehumidifier in Engineering Equation Solver (EES). Afterwards, a parametric analysis of the system is performed including various design and climate parameters such as: inlet air humidity ratio, inlet air temperature, regeneration inlet humidity ratio, regeneration temperature, and rotation speed of the wheel. Then, an experimental setup of the system is established in Taxila Pakistan for the real-time performance assessment. The results revealed that the optimal rotation speed of desiccant wheel ranged from 15-17 rph. The maximum model based and experimental effectiveness is 0.45 and 0.43, respectively at regeneration temperature of 80°C. The maximum and minimum root mean square error (RMSE) values for effectiveness are 3.2% and 2.1%, respectively. Thus, the comparison between experimental and model results showed a good agreement.
PAPER REVISED: 2017-05-18
PAPER ACCEPTED: 2017-07-17
  1. M. Mijakowski, J. Sowa, An attempt to improve indoor environment by installing humidity-sensitive air inlets in a naturally ventilated kindergarten building. Building and Environment, 2017. 111: p. 180-191.
  2. M.O.Kelly, M.E.Walter, J.R. Rowland, Simulated hygrothermal performance of a desiccant-assisted hybrid air/water conditioning system in a mixed humid climate under dynamic load. Energy and Buildings, 2015. 86: p. 45-57.
  3. J.F.Straube, Moisture in buildings. ASHRAE journal, 2002. 44(1): p. 15.
  4. D.B.Jani, M. Mishra, and P.K. Sahoo, Performance studies of hybrid solid desiccant-vapor compression air-conditioning system for hot and humid climates. Energy and Buildings, 2015. 102: p. 284-292.
  5. A.Bahman, L.Rosario, M.M.Rahman, Analysis of energy savings in a supermarket refrigeration/HVAC system. Applied Energy, 2012. 98: p. 11-21.
  6. F.Xiao, G. Ge, X. Niu, Control performance of a dedicated outdoor air system adopting liquid desiccant dehumidification. Applied Energy, 2011. 88(1): p. 143-149.
  7. X.Wang, et al., A hybrid dehumidifier model for real-time performance monitoring, control and optimization in liquid desiccant dehumidification system. Applied Energy, 2013. 111: p. 449-455.
  8. M.Fauchoux, et al., Testing and modelling of a novel ceiling panel for maintaining space relative humidity by moisture transfer. International Journal of Heat and Mass Transfer, 2010. 53(19-20): p. 3961-3968.
  9. N.Wang, J. Zhang, X. Xia, Desiccant wheel thermal performance modeling for indoor humidity optimal control. Applied Energy, 2013. 112: p. 999-1005.
  10. D.La, et al., Technical development of rotary desiccant dehumidification and air conditioning: A review. Renewable and Sustainable Energy Reviews, 2010. 14(1): p. 130-147.
  11. V.Shanmugam, E. Natarajan, Experimental study of regenerative desiccant integrated solar dryer with and without reflective mirror. Applied Thermal Engineering, 2007. 27(8-9): p. 1543-1551.
  12. M.Beccali, et al., Simplified models for the performance evaluation of desiccant wheel dehumidification. International Journal of Energy Research, 2003. 27(1): p. 17-29.
  13. M.Beccali, et al., Update on desiccant wheel model. International Journal of Energy Research, 2004. 28(12): p. 1043-1049.
  14. C.R. Ruivo, G. Angrisani, The effectiveness method to predict the behaviour of a desiccant wheel: An attempt of experimental validation. Applied Thermal Engineering, 2014. 71(2): p. 643-651.
  15. A.E.Kabeel, Solar powered air conditioning system using rotary honeycomb desiccant wheel. Renewable Energy, 2007. 32(11): p. 1842-1857.
  16. J.L.Niu, L.Z. Zhang, Effects of wall thickness on the heat and moisture transfers in desiccant wheels for air dehumidification and enthalpy recovery. International Communications in Heat and Mass Transfer, 2002. 29(2): p. 255-268.
  17. M.Ali Mandegari, H. Pahlavanzadeh, Introduction of a new definition for effectiveness of desiccant wheels. Energy, 2009. 34(6): p. 797-803.
  18. D.Pandelidis, et al., Comparison of desiccant air conditioning systems with different indirect evaporative air coolers. Energy Conversion and Management, 2016. 117: p. 375-392.
  19. E.Elgendy, A. Mostafa, M. Fatouh, Performance enhancement of a desiccant evaporative cooling system using direct/indirect evaporative cooler. International Journal of Refrigeration, 2015. 51: p. 77-87.
  20. I.Uckan, T. Yılmaz, O. Büyükalaca, Effect of operation conditions on the second law analysis of a desiccant cooling system. Applied Thermal Engineering, 2017. 113: p. 1256-1265.
  21. A.Sohani, et al., A novel approach using predictive models for performance analysis of desiccant enhanced evaporative cooling systems. Applied Thermal Engineering, 2016. 107: p. 227-252.
  22. P.M.Cuce, Thermal performance assessment of a novel liquid desiccant-based evaporative cooling system: An experimental investigation. Energy and Buildings, 2017. 138: p. 88-95.
  23. A.Gagliano, et al., Performance assessment of a solar assisted desiccant cooling system. Thermal Science, 2014. 18(2): p. 563-576.
  24. M.Ali, et al., Development and validation of a desiccant wheel model calibrated under transient operating conditions. Applied Thermal Engineering, 2013. 61(2): p. 469-480.
  25. ASHRAE,ASHRAE Handbook, American society of heating, refrigerating and air-conditioning engineers. Inc.: Atlanta, GA, USA, 2009.
  26. A.Kodama, et al., Performance evaluation for a thermal swing honeycomb rotor adsorber using a humidity chart. Journal of chemical engineering of Japan, 1995. 28(1): p. 19-24.
  27. A.Kodama, et al., The use of psychrometric charts for the optimisation of a thermal swing desiccant wheel. Applied Thermal Engineering, 2001. 21(16): p. 1657-1674.
  28. A.Kodama, et al., Temperature profile and optimal rotation speed of a honeycomb rotor adsorber operated with thermal swing. Journal of chemical engineering of Japan, 1994. 27(5): p. 644-649.