Comparison of Experimental and Numerical Heat Losses on Air Conditioned Office in Desert Climate


  • Ali M. Wahhad Mechanical and Manufacturing Engineering Department, Putra University Malaysia, Malaysia
  • Nor Mariah Adam Mechanical and Manufacturing Engineering Department, Putra University Malaysia, Malaysia
  • Mohd S.Salit Mechanical and Manufacturing Engineering Department, Putra University Malaysia, Malaysia
  • Ahmed A.B. Alarabi College of Engineering Technology, Hoon, Libya


Double-glazed window, new model office building, desert climate, CFD, heat transfer coefficient


In recent years, the building community has integrated sustainable design concepts that can improve indoor air quality while conserving energy in buildings. A computational fluid dynamics (CFD) simulation program using three-dimensional flow finite difference of k –ε has been used and compared with experimental results. The study was carried in a new air-conditioned administrative office center built in 2002 as part of Libya’s regional development, as shown in Figure 1. The building is located in Hoon City, province of Al Jufrah, Southern Libya, at lat. 7’ N and lat. 56’ E. Experimentally eight thermocouples were placed at eight different positions on the inner surface to measure the surface inner temperature. The main aim of the study is to evaluate the temperature difference between outdoor and indoor and the distribution of the air temperature and the velocity inside the room. The temperature differences between the indoor and outdoor was found to be varied between 9 °C to15 °C. Good agreement was achieved between the computed and measured results. The error percentage was varied from 0.3% to 0.8%. For both inner and outer surface, good agreement between experimental and CFD heat transfer coefficient has been achieved.


Givoni, B. (1981). Man, Climate and Architecture, London: Applied Science Publishers

ASHRAE 2001. 2001 ASHRAE handbook. Atlanta: American Society of Heating,

Refrigerating and Air-Conditioning Engineers, Inc

Pereira, F. O. R; Sharples, S. 1991. The development of a device for measuring solar heat gain and shading coefficients in scale models. Energy and Buildings 17: pp271-281

Anderson JD. Computational fluid dynamics, International Edition, New York: McGraw-Hill; 1995

Baker AJ, Richard MK, Eliott BG, Subrata Roy, Edward GS. Computational fluid dynamics: a two-edged sword. ASHRAE Journal 1997:51–8.

K.W.D. Cheong ∗, E. Djunaedy, Y.L. Chua, K.W. Tham, S.C. Sekhar, N.H. Wong, M.B. Ullah, Thermal comfort study of an air-conditioned lecture theatre in the tropics, Building and Environment 38 (2003) 63 – 73

María José Suárez, Antonio José Gutiérrez, Jorge Pistono, Eduardo Blanco CFD analysis of heat collection in a glazed gallery, Energy and Buildings, Volume 43, Issue 1, January 2011, Pages 108-116

Jorge S. Carlos, Helena Corvacho, Pedro D. Silva, J.P. Castro-Gomes. Modelling and simulation of a ventilated double window, Applied Thermal Engineering, Volume 31, Issue 1, January 2011, Pages 93-102

Kamal A.R. Ismail, Carlos T. Salinas, Jorge R. Henrique. A comparative study of naturally ventilated and gas filled windows for hot climates Energy Conversion and Management, Volume 50, Issue 7, July 2009, Pages 1691-1703

Sujoy Pal, Biswanath Roy, Subhasis Neogi Heat transfer modelling on windows and glazing under the exposure of solar radiation Original Energy and Buildings, Volume 41, Issue 6,

June 2009, Pages 654-661

Ooi Yongsona, Irfan Anjum Badruddina,, Z.A. Zainala, P.A. Aswatha Narayanab 'Airflow analysis in an air conditioning room' Building and Environment 42 (2007) 1531-1537

Sami A. Al-Sanea, M.F. Zedan, M.B. Al-Harbi Heat transfer characteristics in air- conditioned rooms using mixing air-distribution system under mixed convection conditions International Journal of Thermal Sciences, Volume 59, September 2012, Pages 247-259

Murakami S, Kato S, Nakagawa H. Numerical prediction of horizontal non-isothermal 3-D jet in room based on the k-model. ASHRAE Transactions 1991; 97(1):38–48.

H.B. Awbi, M.M. Nemri, Scale effect in room airflow studies, Energy and Buildings 14 (1990) 207-210.

Jiang He, Akira Hoyano. Measurement and simulation of the thermal environment in the built space under a membrane structure, Building and Environment Volume 44, Issue 6,

June 2009, Pages 1119–1127

Huang H, Ooka R, Kato S. Urban thermal environment measurements and numerical simulation for an actual complex urban area covering a large district heating and cooling system in summer. Atmos Environ 2005;39:6362–75

Tanimoto J, Hagishima A, Chimklai P. An approach for coupled simulation of building thermal effects and urban climatology. Energ Build 2004;36:781–93

Zhai JZ, Chen YQ. Sensitivity analysis and application guides for integrated building energy and CFD simulation. Energ Build 2006;38:1060–8.

Li X, Yu Z, Zhao B, Li Y. Numerical analysis of outdoor thermal environment around buildings. Build Environ 2005; 40:853-66.

Clarke J.A. Energy simulation in building design, Adam Hilger Ltd.; 1985

Institute for building environment and energy conservation (IBEC) SMASH for Windows Ver.2 user’s manual; 2000 (in Japanese)

Harayama K et al. Numerical study based on unsteady radiation and conduction analysis prediction of outdoor environment with unsteady coupled simulation of convection, part 1. J Archit Plan (Trans AIJ) 2002;556:99-106 (in Japanese).

Kim T, Kato S, Murakami S. Indoor cooling/heating load analysis based on coupled simulation of convection, radiation and HVAC control. Building and Environment 2001; 36:901–8.

Murakami S, Kato S, Kondo Y, Takahashi Y, Choi DH. Analysis of an indoor thermal environment using the CFD method (part 1), CFD solutions and its application to indoor models. Transactions of the Society of Heating, Air-conditioning and Sanitary Engineers of Japan 1995; 57:105–15 (in Japanese).

Holman, J. P.2002. Heat Transfer. 9th Edition, Mc Graw Hill. New York.