Design-Stage Analytical and CFD Assessment of a Coconut Oil–Fly Ash Composite PCM Partition Wall with Fan-Assisted Ventilation for Tropical Residential Cooling
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Abstract
Masonry dwellings in tropical Indonesia often exceed the indoor comfort range on hot afternoons, encouraging reliance on split-unit air conditioning (AC). This study presents a design-stage assessment of a partition wall containing 918 polyethylene spheres (12 cm) filled with a coconut oil–fly ash composite phase change material (PCM; 50 vol% oil, 40 vol% fly ash, 10 vol% air) and assisted by exhaust fans (24 W in total), for two bedrooms of a Type-36 house in Bandung. A Maxwell-Eucken estimate indicates that fly ash raises the composite thermal conductivity from 0.17 to about 0.32 W/m·K (0.24–0.36 W/m·K). A quasi-steady melting analysis shows that capsule charging is limited mainly by surface convection: the latent heat absorbed during a 5-h afternoon (2.0–3.7 kWh for the whole wall) is similar to that of pure-oil capsules, while the composite uses 44% less oil and completes its melting cycle faster. The installed 373.8 kg of oil corresponds to a theoretical air-temperature reduction of up to 4.0 °C in the 49.5 m³ rooms. A steady-state CFD simulation (Butterfly/OpenFOAM) for the EPW design hour (9 December, 14:00; outdoor 29.0 °C), with the PCM surface prescribed at 25.5 °C, gives an indoor air temperature of 26.33 °C against 28.30 °C for brick partitions, within the ASHRAE 55 adaptive comfort limits. Operating electricity and CO₂ emissions are 95–97% lower than for two ½ PK AC units, with a simple payback of about 3.3 years; as the AC provides lower temperatures and dehumidification, these are upper bounds. Transient coupled simulation and prototype testing are required for validation.
References
[1] IEA, The Future of Cooling: Opportunities for Energy-Efficient Air Conditioning, International Energy Agency, Paris, 2018. Available: https://www.iea.org/reports/the-future-of-cooling
[2] M. Lachheb, Z. Younsi, N. Youssef, S. Bouadila, Enhancing building energy efficiency and thermal performance with PCM-integrated brick walls: A comprehensive review, Building and Environment, 256, 2024, 111476. doi: 10.1016/j.buildenv.2024.111476
[3] A. Jurizat, Penurunan temperatur ruang dalam dengan menggunakan dinding massa termal internal di rumah bata, Master's thesis, Department of Architecture, Institut Teknologi Bandung, Bandung, 2019.
[4] H. M. Teamah, M. Teamah, Phase change materials integration in building envelopes under different climatic conditions: State of the art, opportunities, and challenges, Energy Storage, 7(5), 2025, e70250. doi: 10.1002/est2.70250
[5] A. Yadav, A. K. Pandey, M. Samykano, B. Kalidasan, Z. Said, A review of organic phase change materials and their adaptation for thermal energy storage, International Materials Reviews, 69(7–8), 2024, pp. 380–446. doi: 10.1177/09506608241292406
[6] J. Lei, J. Yang, E.-H. Yang, Energy performance of building envelopes integrated with phase change materials for cooling load reduction in tropical Singapore, Applied Energy, 162, 2016, pp. 207–217. doi: 10.1016/j.apenergy.2015.10.031
[7] C. Eller, M. Rida, K. Boudier, C. Otoni, G. Celani, L. Labaki, S. Hoffmann, Climate-based analysis for the potential use of coconut oil as phase change material in buildings, Sustainability, 13(19), 2021, 10731. doi: 10.3390/su131910731
[8] S. Kahwaji, M. A. White, Edible oils as practical phase change materials for thermal energy storage, Applied Sciences, 9(8), 2019, 1627. doi: 10.3390/app9081627
[9] S. Wonorahardjo, I. M. Sutjahja, D. Kurnia, Z. Fahmi, W. A. Putri, Potential of thermal energy storage using coconut oil for air temperature control, Buildings, 8(8), 2018, 95. doi: 10.3390/buildings8080095
[10] S. Wonorahardjo, I. M. Sutjahja, D. Kurnia, Potential of coconut oil for temperature regulation in tropical houses, Journal of Engineering Physics and Thermophysics, 92(1), 2019, pp. 80–88. doi: 10.1007/s10891-019-01909-7
[11] W. A. Putri, Z. Fahmi, I. M. Sutjahja, D. Kurnia, S. Wonorahardjo, Thermophysical parameters of coconut oil and its potential application as the thermal energy storage system in Indonesia, Journal of Physics: Conference Series, 739, 2016, 012065. doi: 10.1088/1742-6596/739/1/012065
[12] A. Li, Y. Yang, Y. Ren, Y. Wan, W. Wu, H. Zhang, Bio-based composite phase change material utilizing wood fiber and coconut oil for thermal management in building envelopes, Journal of Cleaner Production, 469, 2024, 143177. doi: 10.1016/j.jclepro.2024.143177
[13] A. Ismail, J. Wang, B. A. Salami, L. O. Oyedele, G. K. Otukogbe, Microencapsulated phase change materials for enhanced thermal energy storage performance in construction materials: A critical review, Construction and Building Materials, 401, 2023, 132877. doi: 10.1016/j.conbuildmat.2023.132877
[14] H. Jiang, C. Yang, J. Song, P. J. Cao, J. Chen, J. Wang, W. Hong, Efficient enhancement of heat storage capacity of polyethylene glycol phase change material based on a novel fly ash support, ACS Sustainable Chemistry & Engineering, 12(19), 2024, pp. 7382–7391. doi: 10.1021/acssuschemeng.4c00354
[15] P.-E. Bat-Erdene, S. Pareek, Experimental study on the development of fly ash foam concrete containing phase change materials (PCMs), Materials, 15(23), 2022, 8428. doi: 10.3390/ma15238428
[16] A. de Gracia, Dynamic building envelope with PCM for cooling purposes – Proof of concept, Applied Energy, 235, 2019, pp. 1245–1253. doi: 10.1016/j.apenergy.2018.11.061
[17] S. Zhou, M. Song, K. Shan, L. Zhang, B. You, A. G. Razaqpur, Heating and energy performances of a dynamic Trombe wall incorporating phase change materials under different operation modes, Journal of Building Engineering, 95, 2024, 110201. doi: 10.1016/j.jobe.2024.110201
[18] Government of the Republic of Indonesia, Peraturan Pemerintah Nomor 22 Tahun 2021 tentang Penyelenggaraan Perlindungan dan Pengelolaan Lingkungan Hidup, Lembaran Negara Republik Indonesia Tahun 2021 Nomor 32, Jakarta, 2021.
[19] A. Widayanti, R. A. A. Soemitro, H. Suprayitno, J. J. Ekaputri, Characterization and compressive strength of fly ash based-geopolymer paste, MATEC Web of Conferences, 195, 2018, 01023. doi: 10.1051/matecconf/201819501023
[20] L. Atmaja, H. Fansuri, A. Maharani, Crystalline phase reactivity in the synthesis of fly ash-based geopolymer, Indonesian Journal of Chemistry, 11(1), 2011, pp. 90–95. doi: 10.22146/ijc.21426
[21] A. Jurizat, G. Kresnadian, F. M. Ikhsanudin, Peningkatan kemampuan minyak kelapa sebagai phase change material dengan menggunakan fly ash untuk mengendalikan temperatur ruang dalam, Bukit Asam Innovation Award 2022: Greenovator, Bandung, 2022.
[22] A. Jurizat, H. Andoni, I. M. Sutjahja, Cell sizes study of encapsulated coconut oil for heat exchanger application, in: Proceedings of the International Conference on Building Science and Technology, Bandung, 2018.
[23] J. Wang, J. K. Carson, M. F. North, D. J. Cleland, A new approach to modelling the effective thermal conductivity of heterogeneous materials, International Journal of Heat and Mass Transfer, 49(17–18), 2006, pp. 3075–3083. doi: 10.1016/j.ijheatmasstransfer.2006.02.007
[24] D. P. Bentz, M. A. Peltz, A. Durán-Herrera, P. Valdez, C. A. Juárez, Thermal properties of high-volume fly ash mortars and concretes, Journal of Building Physics, 34(3), 2011, pp. 263–275. doi: 10.1177/1744259110376613
[25] V. Alexiades, A. D. Solomon, Mathematical Modeling of Melting and Freezing Processes, Hemisphere Publishing Corporation, Washington, DC, 1993.
[26] Ladybug Tools, Butterfly: A plugin to create and run OpenFOAM cases from Grasshopper and Dynamo, source code (recipe.py, turbulenceProperties.py). Available: https://github.com/ladybug-tools/butterfly
[27] Badan Standardisasi Nasional, SNI 03-6572-2001: Tata cara perancangan sistem ventilasi dan pengkondisian udara pada bangunan gedung, BSN, Jakarta, 2001.
[28] ASHRAE, ANSI/ASHRAE Standard 55-2020: Thermal Environmental Conditions for Human Occupancy, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, 2020.
[29] Z. Abilkhassenova, S. A. Memon, A. Ahmad, A. Saurbayeva, J. R. Kim, Utilizing the Fanger thermal comfort model to evaluate the thermal, energy, economic, and environmental performance of PCM-integrated buildings in various climate zones worldwide, Energy and Buildings, 297, 2023, 113479. doi: 10.1016/j.enbuild.2023.113479
[30] Direktorat Jenderal Ketenagalistrikan, Faktor Emisi Gas Rumah Kaca Sistem Ketenagalistrikan Tahun 2019, Kementerian Energi dan Sumber Daya Mineral, Jakarta, 2019; established by Keputusan Menteri ESDM Nomor 163.K/HK.02/MEM.S/2021.
[31] I. Febijanto, Perhitungan faktor emisi di sistem jaringan ketenagalistrikan Jawa-Madura-Bali, Jurnal Teknologi Lingkungan, 11(2), 2010, pp. 227–237.
[32] Kementerian Energi dan Sumber Daya Mineral, Peraturan Menteri ESDM Nomor 8 Tahun 2023 tentang Perubahan atas Peraturan Menteri ESDM Nomor 28 Tahun 2016 tentang Tarif Tenaga Listrik yang Disediakan oleh PT Perusahaan Listrik Negara (Persero), Jakarta, 2023; tariff level for 2026 confirmed in Siaran Pers No. 102.Pers/04/SJI/2025, 31 December 2025.
[33] Kementerian Pekerjaan Umum dan Perumahan Rakyat, Peraturan Menteri PUPR Nomor 1 Tahun 2022 tentang Pedoman Penyusunan Perkiraan Biaya Pekerjaan Konstruksi Bidang Pekerjaan Umum dan Perumahan Rakyat, Kementerian PUPR, Jakarta, 2022.
[34] K. Faraj, M. Khaled, J. Faraj, F. Hachem, C. Castelain, A summary review on experimental studies for PCM building applications: Towards advanced modular prototype, Energies, 15(4), 2022, 1459. doi: 10.3390/en15041459
[35] A. Demirbaş, Fuel properties and calculation of higher heating values of vegetable oils, Fuel, 77(9–10), 1998, pp. 1117–1120. doi: 10.1016/S0016-2361(97)00289-5
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