New Energy Exploitation and Application


The Performance Evaluation of Ventilated Windows in the Simultaneous Improvement of Energy Efficiency and Indoor Air Quality in Office Buildings: A Case Study


  • Farid Khalvati Department of Mechanical Engineering, Shiraz University of Technology, Shiraz, Iran
  • Amir Omidvar
    Department of Mechanical Engineering, Shiraz University of Technology, Shiraz, Iran


Khalvati, F., & Omidvar, A. (2021). The Performance Evaluation of Ventilated Windows in the Simultaneous Improvement of Energy Efficiency and Indoor Air Quality in Office Buildings: A Case Study. New Energy Exploitation and Application, 1(1), 8–16.
Energy efficiency and indoor air quality (IAQ) are two crucial required features in a building. Simultaneous improvement of energy efficiency and IAQ in a building can pave the way for obtaining a green building certification. This paper examined the performance of the airflow windows’ supply and exhaust operating modes in energy-saving and providing IAQ criteria. The analytical zonal model coupled with the airflow network model was used to evaluate the system’s thermal performance and the induced airflow. The simulation was done for an office building located in Shiraz, Iran. The results showed that the energy performance of ventilated windows is positive in nine months of the year. Compared to a conventional double-glazed window, the maximum energy savings is about 10%, which occurs in August. It is predicted that using ventilated windows in office buildings in Shiraz can improve the window’s thermal performance by an average of about 5%. The results also showed that ventilated windows could provide the fresh air needed for the building in 250 days of the year to achieve the desired IAQ index (based on ASHRAE 62.1 standard). Furthermore, the effects of glass aspect ratio, airflow channel thickness, and the size of inlet/outlet openings on energy efficiency and IAQ of the suggested window were studied. Results indicated that in the climatic conditions of Shiraz, the exhaust operating mode is much more efficient than the supply mode.


Ventilated window Airflow window Energy efficiency Indoor air quality


  1. Cincinelli, A., Martellini, T., 2017. Indoor Air Quality and Health. Int. J. Environ. Res. Public Health. 14(11), 1286.DOI:
  2. European Collaborative Action, 1996. Indoor Air Quality and the Use of Energy in Buildings.’s%20impact%20on%20man.pdf (Accessed 13 May 2021).
  3. Hobday, R., 2005. Technical synthesis report, Annex31, Energy-related environmental impact of buildings, Faber Maunsell Ltd, UK.
  4. ASHRAE, 2013. Ventilation for Acceptable Indoor Air Quality. ANSI/ASHRAE Standard 62.1
  5. CEN, 2014. Ventilation for buildings (CEN/TC 156).
  6. Gosselin, J.R., Chen, Q., 2008. A dual airflow window for indoor air quality improvement and energy conservation in buildings. HVAC&R Research. 14(3), 359-372.DOI:
  7. Chow, T.T., Lin, Z., He, W., Chan, A.L.S., Fong, K.F., 2006. Use of ventilated solar screen window in warm climate. Appl. Therm. Eng. 26, 1910-1918.DOI: 2006.01.026.
  8. Carlos, J.S., Corvacho, H., 2013. Ventilated double window for the preheating of the ventilation air comparison of its performance in a northern and a southern european climate. J. Renew. Energy. 1-12.DOI:
  9. Zhang, C., Wang, J., Xu, X., Zou, F., Yu, J., 2016.Modeling and thermal performance evaluation of a switchable triple glazing exhaust air window. Appl. Therm. Eng. 92, 8-17.DOI:
  10. Khalvati, F., Omidvar, A., 2019. Summer study on thermal performance of an exhausting airflow window in evaporatively-cooled buildings. Appl. Therm. Eng. 153, 147-158.DOI:
  11. Khalvati, F., Omidvar, A., Hadianfard, F., 2021. Study on summer thermal performance of a solar ventilated window integrated with thermoelectric air-cooling system. Int. J. Energy Environ. Eng.DOI:
  12. Ghadimi, M., Ghadamian, H., Hamidi, A.A., Fazelpour, F., Behghadam, M.A., 2012. Analysis of free and forced convection in airflow windows using numerical simulation of heat transfer. Int. J. Energy Environ. Eng. 3, 14. DOI:
  13. Zhang, N., Jin, W., He, J., 2016. Experimental study on the influence of ventilated window on indoor air quality and energy consumption. Procedia Eng. 146, 296-302.DOI:
  14. Chow, T.T., Lin, Z., Pie, G., Chan, A.L.S., Fong, K.F., 2009. A comparative study of PV glazing performance in warm climate. Indoor Built Environ. 18, 32-40.DOI: 1420326X08100323.
  15. Hweij, W.A., Al Touma, A., Ghali, K., Ghaddarn N., 2017. Evaporatively-cooled window driven by solar chimney to improve energy efficiency and thermal comfort in dry desert climate. Energy Build. 139, 755-761.DOI:
  16. Jiru, T.E., Haghighat, F., 2008. Modeling ventilated double skin facade-A zonal approach. Energy Build. 40, 1567-1576. DOI:
  17. Clarke, J.A., Hensen, J.L.M., 1991. An approach to the simulation of coupled heat and mass flow in buildings. In: 11th AIVC Conference of Ventilation System Performance. IEA Air Infiltration and Ventilation Center, Belgirate. pp. 339-354.
  18. Churchill, S.W., Chu, H.H.S., 1875. Correlating equations for laminar and turbulent free convection from a vertical plate. Int. J. Heat Mass Transf. 18, 1323-1329.DOI:
  19. Ito, N., Kimura, K., Oka, J., 1972. A field experimental study on the convective heat transfer coefficient on exterior surface of a building. In: ASHRAE Transactions. 78, part 1.
  20. Bar-Cohen, A., Rohsenow, W.M., 1984. Thermally optimum spacing of vertical, natural convection cooled, parallel plates. In: Transactions of the ASME.
  21. Badr, H.M., Habib, M.A., Anwar, S., Ben-Mansour, R., Said, S.A.M., 2006. Turbulent natural convection in vertical parallel-plate channels. Heat and Mass Transfer. 43, 73-84.DOI: