A Numerical Study to Determine the Effect of an Insulator Location on the Transient Heat Transfer

• Autorzy: Mageed Ridha Hameed , Kurji Hayder J. , Abdulrasool Ali A.

Identyfikatory

DOI

10.12911/22998993/170035

• Języki publikacji: EN

Abstrakty

EN

Given the importance of thermal insulation in the walls of buildings to provide both electrical energy and thermal comfort in different weathers. In this research, the ANSYS-14 simulation program was used, considered one of the programs used to evaluate the thermal behavior of buildings, considering the effect of weather changes and building components during the steady and unsteady heat transfer of a composite wall from several layers. The simulation program was used for four types of insulation inside the wall with different thermal properties (Glass-Fiber Slab, Polyurethane Board, Hardboard (Medium) and Softwoods). A model was built for a traditional wall without an insulator and a model for a traditional wall that contains an insulator in different locations (from the outside, in the middle, and from the inside). Also, the model was isolated from the top and bottom surfaces, and each insulation material was applied in three locations in the wall. The conventional composite wall was exposed to a constant thermal load of 60 °C from the outside, and the inside wall was exposed to a thermal load of 25 °C This study focused on three steps. The first step is to know the best type of the four thermal insulators used in this study. The second step was to evaluate the best location of the insulator in the wall. The third step included the results of the previous two steps through which the best insulator was chosen and the best location in the wall. Three values of insulator thickness 2, 5 and 8 cm were used. Through the results of the study, it was found that placing the insulator on the outside of the wall plays a large role in reducing the rate of unsteady heat transfer and that its effect decreases by approaching the steady state, as it does not affect it in the case of the total steady state. The results also showed that the rate of unsteady heat transfer decreases by decreasing the thermal diffusivity of materials. It is also noticeable that the effect of the density and specific heat capacity appears clearly at the beginning of the thermal loading on the material. That effect decreases by approaching the steady state as the effect of the heat transfer coefficient of conduction appears. It was also found that both hardboard and polyurethane are the best in thermal insulation. It was also observed that the relationship between heat transfer rate and thickness is inverse-linear.

Słowa kluczowe

EN

unsteady heat transfer; thermal properties; numerical method; heat transfer; thermal conduction

• Wydawca: Polskie Towarzystwo Inżynierii Ekologicznej ; Lublin University of Technology
• Czasopismo: Journal of Ecological Engineering
• Rocznik: 2023
• Tom: Vol. 24, nr 10
• Strony: 105--114
• Opis fizyczny: Bibliogr. 20 poz., rys., tab.

Twórcy

autor

Mageed Ridha Hameed

• Department of Mechanical Technology/Technical Institute of Karbala, Al-Furat Al-Awsat Technical University, Kerbela University, College of Engineering, Mechanical Department, Kerbela, Iraq

autor

Kurji Hayder J.

• Department of Mechanical Technology/Technical Institute of Karbala, Al-Furat Al-Awsat Technical University, Kerbela University, College of Engineering, Mechanical Department, Kerbela, Iraq

• https://orcid.org/0000-0002-6873-1112

autor

Abdulrasool Ali A.

• Department of Mechanical Technology/Technical Institute of Karbala, Al-Furat Al-Awsat Technical University, Kerbela University, College of Engineering, Mechanical Department, Kerbela, Iraq

Bibliografia

• 1. Pekdogan T. and Basaran T., 2017. Thermal performance of different exterior wall structures based on wall orientation. Applied Thermal Engineering, 112, 15–24.
• 2. Chiba R., 2018. An analytical solution for transient heatconduction in a composite slab with time-dependent heat transfer coefficient. Mathematical Problems in Engineering, Article ID 4707860.
• 3. Izquierdo-Barrientos M.A., 2012. A numerical study of external building walls containing phase change materials (PCM). Applied Thermal Engineering, 47, 73–85.
• 4. Arkar C. and Domjan S., 2018. Lightweight composite timber façade wall with improved thermal response. Sustainable Cities and Society, 38, 325–332.
• 5. Wange N.J., Gaikwad M.N., Pawar S.P., 2017. Analytical solution for three-dimensional unsteady heat conduction in a multilayer cylinder with volumetric heat source. International Journal of Advanced Engineering, Management and Science, 2, 285-291.
• 6. Jayakumar J. 2017. Study of one dimensional conduction heat transfer for constant thermal conductivity through composite plane slab and in cylinder at steady state condition. International Journal of Mechanical Engineering and Technology, 8(11), 456-465.
• 7. Fakoor-Pakdaman M., Ahmadi M., Bagheri F., 2015. Optimal time-varying heat transfer in multilayered packages with arbitrary heat generations and contact resistance. Journal of Heat Transfer, 137, 081401.
• 8. Feng Zhu, Chuan Zhang, Xiaolu Gong, 2016. Numerical analysis and comparison of the thermal performance enhancement methods for metal foam/phase change material composite. Applied Thermal Engineering, 109, 373-383.
• 9. Ozel M., 2014. Effect of insulation location on dynamic heat-transfer characteristics of building external walls and optimization of insulation thickness. Energy and Buildings, 72, 288-295.
• 10. Ioannis A., Petros A., John G., 2014. Optimum insulation thickness for external walls on different orientations considering the speed and direction of the wind. Applied Energy, 117, 167-175.
• 11. Aditya L., Mahlia T.M.I., Rismanchi B., 2017. A review on insulation materials for energy conservation in buildings. Renewable and Sustainable Energy Reviews, 73, 1352-1365.
• 12. Boostani H. and Hancer P., 2018. A model for external walls selection in hot and humid climates. Journal of Sustainability, 100, 1-23.
• 13. Ho Baik and Minju Kim, 2018. Simulation model for productivity analysis of external insulated precast concrete wall system. Journal of Sustainability, 105, 1-20.
• 14. Jinghua Yu and Hong Ye, 2018. Experimental study on the thermal performance of a hollow block ventilation wall. International Journal of Renewable Energy,. 122A, 619-631.
• 15. Pekdoğan T. and Başaran T., 2018. Parametric transient analysis of thermal insulating plaster for exterior wall. 3rd International Conference on Thermophysical and Mechanical Properties of Advanced Materials, pp. 63-75.
• 16. Ozel M., 2011. Thermal performance and optimum insulation thickness of building walls with different structure materials. Journal of Applied Thermal Engineering, 31(17-18), 3854-3863.
• 17. Fathipour R. and Hadidi A., 2017. Analytical solution for the study of time lag and decrement factor for building walls in climate of Iran. International Journal of Energy, 134, 167-180.
• 18. Integrated Environmental Solutions, 2015. Apache tables user guide-IES virtual environment. Integrated Environmental Solutions Ltd.
• 19. Cengel Y.A. 2008. Introduction to Thermodynamics and Heat Transfer. Appendix 1: Property tables and charts (SI units). 2nd Ed., McGraw Hill, New York, USA, 765-808.
• 20. Holman J.P. 1986. Heat transfer. McGraw Hill, New York, USA.