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Heat transfer analysis and thermal optimisation of building envelopes in Tibetan Plateau |
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| รหัสดีโอไอ | |
| Creator | Mingshan Zhang |
| Title | Heat transfer analysis and thermal optimisation of building envelopes in Tibetan Plateau |
| Contributor | Yin Zhang |
| Publisher | Maejo University |
| Publication Year | 2561 |
| Journal Title | Maejo International Journal of Science and Technology |
| Journal Vol. | 12 |
| Journal No. | 2 |
| Page no. | 124 |
| Keyword | Tibetan Plateau, heat transfer, building envelope, external wall, thermal insulation |
| Website title | Maejo International Journal of Science and Technology |
| ISSN | 1905-7873 |
| Abstract | Tibetan Plateau has an extremely harsh and cold climate and scarce natural resources but abundant solar energy. Optimisation of thermal design for buildings is highly essential for indoor thermal comfort improvement and energy efficiency of buildings. In this paper a modified heat transfer model of building envelopes in Tibetan Plateau is established, considering locally unique climatic features. Furthermore, the influence of low air density on convection is analysed and heat transfer correction factor is used to evaluate the effects of solar and long-wave radiations on external walls of buildings from different directions. The results show that the convection coefficients decline with rising elevation and heat-transfer correction factor decreases with increasing solar radiation. It also indicates that by aiming at minimising overall heat loss, the optimal thermal resistance of each external wall should be in positive proportion to the square root of its heat-transfer correction factor. A case study in Lhasa illustrates that inserting thermal insulation materials into the external walls can significantly improve indoor thermal comfort. Compared to balanced thermal insulation, the integrated uncomfortable degree of unbalanced thermal insulation can be reduced by about 20% after optimisation. This work is important for guiding the practical thermal design of buildings in plateau areas. |
