Document Type : Original Article
Department of Education, Samangan University, Afghanistan
Physics department University of Tehran
Department of Physics, University of Tehran
The purpose of this study is to reduce the temperature of the attic of the building of department of physics in university of Tehran. To achieve this goal, eighteen natural ventilators with the area of 0.25 m2 each were installed on the roof. The natural ventilators alone did not decrease the temperature significantly. To help natural ventilation, a laminar flow of air from the floors to the attic was provided. This led to a temperature decrease around 1.5 to 2o C. In addition, a powered ventilation was resulted 3 to 8o C temperature decrease. Since the volume (4533 m3) and area (1416 m2) of the attic are too large, further tests were conducted on two small models (47×33×51 cm3) of the attic, build from the same material as the main attic. The models were used to investigate the effect of covering the roof with aluminum foil and painting the roof with a withe color as a reflector, and installation of polystyrene panels under the roof as an insulator. Covering with aluminum foil, painting in withe, and installation of polystyrene resulted in 3-5, 2-3.5, and 1-2 degrees decrease in temperature, respectively. Reason of these changes was explained by reflection spectrum of UV-Vis-NIR spectrophotometry. Finally, the attic was simulated by the COMSOL Multiphysics software. It showed that a temperature reduction of 10 degrees could be accomplished by installation of six fans as inlet in the gables, three in each gable. Each fan has to generate 4 m/sec air flow velocity.
- Z Zheng, et al., Energy Procedia Journal 142 (2017) 2317.
- M Saqafi , “Renewable Energies”, Tehran, University of Tehran press, (2009) (in Persian)
- C King George, “Physics of Energy Sources” Manchester, UK, John Wiley (2018).
- E D O Orga, , Energy Agency, (2017) 1.
- A Mohajer Milani and S Heidari, IJE 4 (2017) 19 (in Persian).
- E Rajablo and H Saadullah, “optimization of energy consumption in buildings; Complete guide to Audit optimization software: process and report of energy consumption optimization calculations in a school, Tehran”, Yazda Publications, (2011) (in Persian).
- Y Eren, B I Küçükdemiral, and I Üstoğlu, “Introduction to optimization optimization in renewable energy systems”, Istanbul, Turkey, Elsevier Ltd (2017).
- G A Kamali and I Mordadi, “Sun radiation; principles and applications in agriculture and new energies”, Tehran, 21st Century Research and Meteorological Research Institute Publications (2005) (in Persian).
- B Clive, “Energy: management, supply and consumption optimizationTehran”, Nezhat Sharqi Sabz (2005) (in Persian).
- R Ehrlich and H A Geller, “Renewable Energy, Second Edition A First Course” CRC Press (2018).
- M Sultani and A Taqi Nazari, “Optimization of fuel consumption in central heating systems”, Tehran: Fadak Isatis, (2007) (in Persian).
- S Sattari, et al., “Solutions for managing and optimizing energy consumption in the country”, Tehran, Hazare Swom Andishe (2009) (in Persian).
- M Tahbaz and S Djalilian, “Outdoor Microclimate and Pavement Material - Case Study in University Site. Honar-Ha-Ye-Ziba: Memary Va Shahrsazi”, University of Tehran 20 (2016) 21 (in Persian).
- S Aghanajafi and A Dehghani, “Solar radiant heat transfer and its application in buildings” Tehran, K N Toosi University of Technology (2007) (in Persian).
- C Rubio Bellido, A Pérez Fargallo, and J Pulido Arcas, “Energy Optimization and Prediction in Office Buildings A Case Study of Office Building Design in Chile”, Springer Briefs in Energy (2018).
- A Shahin, “Energy Management”, Isfahan, Jihad Daneshgahi Isfahan (2004) (in Persian).
- H Sadeghi, “Development approaches of energy consumption optimization groups”, Fuel consumption optimization company (2006) (in Persian).
- X Wang, et al., Applied Energy Journal 104 (2013) 337.
- J Khodakarami and P Ghobadi, JEM 6 (2016) 12 (in Persian).
- A K Dahiya and P Vasudevan, Energy Journal 11 (1986) 685.
- S Houda, R Belarbi, and N Zemmouri, Energy Procedia Press 139 (2017)
- A Campo and J Sieres, The International Journal of Thermal and Environmental Engineering 12 (2016) 39.
- A Pisello, M Bobker, and F Cotana, Occupancy Energies 5 (2017) 5257.