Assessment of Thermal Environment and Indoor Air Quality in University Buildings under Tropical Climate Conditions
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Abstract
This study developed mathematical models for assessing the ventilation performance of a university lecture hall using thermal indoor air quality indicators, which focused on heat distribution and contaminant removal effectiveness. Ventilation effectiveness was modelled through the heat distribution effectiveness ratio (Et) and contaminant removal effectiveness ratio (Ec), developed from temperature and CO₂ concentration data collected at the supply, exhaust, and breathing zones. Data measurements of temperature, CO₂ concentration, and air velocity were collected across multiple zones during morning and afternoon lecture periods between February and April to capture variations in occupancy and outdoor conditions. Results revealed significant spatial and temporal variations in temperature (21.4–38.9 °C) and CO₂ levels (456–2673 ppm), with higher values typically occurring in the afternoon due to increased occupancy and reduced outdoor air supply. The evaluated Et values (0–1.2) indicated generally poor heat distribution and limited air mixing, while Ec values (0.1–0.7) suggested suboptimal contaminant removal, despite occasional improvements linked to increased outdoor air circulation. Occupancy-based ventilation analysis showed that outdoor air supply per person frequently fell below ASHRAE recommendations, particularly during peak afternoon periods. CONTAM airflow simulations corroborated the mathematical model developed from experimental results, indicating low infiltration rates during high occupancy. Overall, the findings demonstrate inadequate ventilation performance, leading to thermal discomfort and compromised indoor air quality, and underscore the need for improved ventilation strategies in densely occupied lecture halls.
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References
Alamin, Y. I., DM.Castilla, M., Álvarez, J. D., & Ruano, A., (2017). An Economic Model-Based Predictive Control to Manage the Users’ Thermal Comfort in a Building. Energies. 10(3):321. https://doi.org/10.3390/en10030321.
ASHRAE. (2007). ASHRAE Standard 62.1-2007: Ventilation for acceptable indoor air quality. American Society of Heating, Refrigerating and Air-Conditioning Engineers.
ASHRAE. (2020). ASHRAE Standard 55: Thermal environmental conditions for human occupancy. American Society of Heating, Refrigerating and Air-Conditioning Engineers.
Awbi, H. B. (2003). Ventilation of buildings. 2nd ed. New York: Taylor & Francis; 2003.
Bastide, A., Allard F., & H. Boyer. Natural ventilation: a new method based on the Walton model applied to cross-ventilated buildings having two large external openings. International Journal of Ventilation. 6(3) (2007) 195-206. https://doi.org/10.1080/14733315.2007.11683777.
Budiakova, M., (2019). Architectural Design of Big Lecture Hall in Relation to Air Conditioning System. IOP Conf. Series: Materials Science and Engineering. 471 (082071). Doi:10.1088/1757-899X/471/8/082071.
Calautit, J. K., Aquino, A. I., Shahzad, S., Nasir, D. S.N.M. & Hughes, B. R. (2017). Thermal comfort and indoor air quality analysis of a low-energy cooling windcatcher. Energy Procedia, 105. pp. 2865-2870. ISSN 1876-6102 (https://doi.org/10.1016/j.egypro.2017.03.634)
Chen, Q., & Glicksman, L. R. (2003). System performance evaluation and design guidelines for displacement ventilation. ASHRAE Transactions, 109(2), 698–709.
Chua, K.J., Chou, S.K., Yang, W.M., & Yan, J., (2013). Achieving better energy-efficient air conditioning – A review of technologies and strategies, Applied Energy. 104 (2013) 87-104. https://doi.org/10.1016/j.apenergy.2012.10.037.
Clements-Croome, D. J. (2008). Sustainable intelligent buildings for people: A review. Intelligent Buildings International, 1(1), 67–86.
Davidová, M. (2021). Breathing Artifacts of Urban BioClimatic Layers for Post-Anthropocene Urban Environment. Sustainability. 13(20), 11307. https://doi.org/10.3390/su132011307 DOI:10.1016/J.APENERGY.2013.09.020
Etheridge, D. & Sandberg, M. (1996). Building ventilation- Theory and measurement. Chichester, UK: John Wiley & Sons; 1996.
Evola, G. & Popov, V. (2006). Computational analysis of wind-driven natural ventilation in buildings, Energy and Buildings. 38(5) (2006) 491-501. https://doi.org/10.1016/j.enbuild.2005.08.008
Fanger, P. O. (1970). Thermal comfort: Analysis and applications in environmental engineering. Danish Technical Press.
Fauzi, H. N., Al-Athas, S. I., & Rini, J. A., (2024). Potential Pollutants and Indoor Air Quality Variables Association towards Implementation of the Breathing Architecture Concept: A Review. 5th International Conference on Empathic Architecture. IOP Conf. Series: Earth and Environmental Science 1301 (2024) 012011. Doi:10.1088/1755-1315/1301/1/012011.
Fikry, A. & Elsayed, A., (2021). Improving the indoor air quality (IAQ) in naturally ventilated lecture hall with a single facade by solar chimneys. Journal of Engineering and Applied Science. 68:29. https://doi.org/10.1186/s44147-021-00027-7.
Hsu, C-N & Tsai, Y-L., (2020). Experimental Measurement and Computational Simulation Analysis of Indoor Air Quality in Office-Integration of Voltage Adsorption Dust Collection Device and Energy Recovery Ventilator. Sensors Mater. 32(12) (2020) 4299–4321. https://doi.org/10.18494/SAM.2020.3143.
ISO7730 (1994) Moderate Thermal Environments. Determination of the PMV and PPD Indices and Specification of the Conditions for Thermal Comfort. International Organisation for Standardisation: Geneva, Switzerland, 1994.
Janssens, A., Willems, L., & Laverge, J., (2009). Performance evaluation of residential ventilation systems based on multi-zone ventilation models, Building Physics Group, Ghent University, Department of Architecture and Urban Planning, Belgium. (2009) pp 1-7.
Kalantar, N.& Borhani, A., (2022), Breathable Walls - Computational Thinking in Early Design Education, Proceedings of the 22nd Conference on Computer Aided Architectural Design Research in Asia (CAADRIA).
Khdair, A. I. & Rumman, G. A., (2022). Adopting PCM and natural ventilation in buildings to reduce energy demand in HVAC -Examining various PCM along with various natural ventilation scenarios J. Build. Eng. 57 p. 104770.
Layeni, A., Nwaokocha, C. Olamide, O., Giwa, S., Tongo, S., Onabanjo, O., Samuel, T., Olanipekun, O., Alabi, O., Adedeji, K., Samuel, O., Jagun Z. O., Folorunsho, O., Adebayo, J. & Oniyide, F., (2020). Computational Analysis of a Lecture Room Ventilation System, in: J. Alberto Pulido Arcas, C. Rubio-Bellido, A. Pérez-Fargallo, & I. Oropeza-Perez, (Eds), Zero-Energy Build - New Approaches Technology, IntechOpen, 2020, pp 1-25. doi: 10.5772/intechopen.92725.
Li, L., Zhang, Y., Fung, J. C.H., Qu, H., & Lau, A. K. H., (2021). A coupled computational fluid dynamics and back-propagation neural network-based particle swarm optimizer algorithm for predicting and optimizing indoor air quality. Building and Environment. 207, 108533. 10.1016/j.buildenv.2021.108533.
Li, Y., Sandberg, M., & Fuchs, L. (2011). Vertical temperature profiles in rooms ventilated by displacement: Full-scale measurement and nodal modelling. Indoor Air, 2(4), 225–243.
McNeill, V. F., Corsi, R., Huffman, J. A., King, C., Klein, R., Lamore, M., Maeng, D. Y., Miller, S. L., Lee Ng, N., Olsiewski, P., Godri Pollitt, K. J., Segalman, R., Sessions, A., Squires, T., & Westgate, S., (2022). Room-level ventilation in schools and universities, Atmospheric Environment: X 13, 100152. https://doi.org/10.1016/j.aeaoa.2022.100152.
Muelas, Á., Remacha, P., Pina, A., Tizné, E., El-Kadmiri, S., Ruiz, A., Aranda, D., & Ballester, J., (2022). Analysis of different ventilation strategies and CO2 distribution in a naturally ventilated classroom, 2022. Atmospheric Environment. 283, 119176, https://doi.org/10.1016/j.atmosenv.2022.119176.
Mundt, E. (2004). Ventilation effectiveness by stratified air distribution systems. Building and Environment, 39(7), 841–850.
Park, K-S., Kim, S-W., Yoon, S-H, (2016). Application of Breathing Architectural Members to the Natural Ventilation of a Passive Solar House. Energies. 9(3), 214. https://doi.org/10.3390/en9030214
Rajkumar, R., Padmanabhan, V., Sundaram, N. M., Kandasamy, U., (2022). A Study on Computational Analysis for Natural Convection in Tall Building – A Macroscopic Approach. Journal of Nanomaterials. 1, 4560064. https://doi.org/10.1155/2022/4560064.
Satish, U., Mendell, M. J., Shekhar, K., Hotchi, T., Sullivan, D., Streufert, S., & Fisk, W. J. (2012). Is CO₂ an indoor pollutant? Direct effects of low-to-moderate CO₂ concentrations on human decision-making performance. Environmental Health Perspectives, 120(12), 1671–1677.
Seppänen, O., Fisk, W. J., & Mendell, M. J. (1999). Association of ventilation rates and CO₂ concentrations with health and other responses in commercial and institutional buildings. Indoor Air, 9(4), 226–252.
Stavridou, A. D., (2015) Breathing architecture: Conceptual architectural design based on the investigation into the natural ventilation of buildings Front. Archit. Res. 4(2) p. 127–145.
Tian, X., Zhang, S., Awbi, H. B., Liao, C., Cheng, Y., Lin, Z., (2020). Multi-indicator evaluation on ventilation effectiveness of three ventilation methods: An experimental study, Building and Environment. 180, 107015. https://doi.org/10.1016/j.buildenv.2020.107015.
Tiderenczl, G., & Matolcsy, K., (2000). Breathing walls: A challenge for new sustainable building techniques in Hungary. Proc. ACEEE Summer Study Energy Effic. Build. 10. 10.281-10.289.
von Spreckelsen, R. M., Harris, M. T., Wigzell, J. M., Fraser, R. C., Carletto, A., Mosquin, D. P. K., Justice, D., & Badyal, J. P. S., (2015). Bioinspired Breathable Architecture for Water Harvesting. Scientific Reports. 5, 16798. https://doi.org/10.1038/srep16798.
Wang, Y., Fu-Yun, Z., Jens, K., Di, L., Jun, L., & Jun-Liang, Z., (2014). Classroom Energy Efficiency and Air Environment with Displacement Natural Ventilation in a Passive Public School Building, Energy and Buildings 70 (2014) 258-270. https://doi.org/10.1016/j.enbuild.2013.11.071.
Wang, Y., Zhao, F., Kuckelkorn, J., Spliethoff, H., & Rank, E., (2014). School building energy performance and classroom air environment implemented with the heat recovery heat pump and displacement ventilation system. Applied Energy. 114 (2014) 58-68.
Yang, L., Yan, H., & Lam, J.C., (2014). Thermal comfort and building energy consumption implications – A review, Applied Energy, Elsevier. 115 (2014) 164-173. https://doi.org/10.1016/j.apenergy.2013.10.062.
Yuan, S., Cai, J., Reniers, G., Yang, M., Chen, C., & Wu, J., (2022). Safety barrier performance assessment by integrating computational fluid dynamics and evacuation modeling for toxic gas leakage scenarios. Reliability Engineering & System Safety. 226,108719. https://doi.org/10.1016/j.ress.2022.108719.
Zhang, Z., Yin, W., Wang, T., & O’Donovan, A., (2022). Effect of cross-ventilation channel in classrooms with interior corridor estimated by computational fluid dynamics. Indoor and Built Environment. 31(2022) 1047 - 1065. 10.1177/1420326X211054341.