| Author: | Wang, Guang |
| Title: | Effect of outdoor pedestrian level turbulence on the convective heat transfer coefficient of human body |
| Degree: | M.Eng. |
| Year: | 2022 |
| Subject: | Heat -- Convection Winds Atmospheric turbulence Hong Kong Polytechnic University -- Dissertations |
| Department: | Department of Building Environment and Energy Engineering |
| Pages: | vii, 87 pages : color illustrations |
| Language: | English |
| Abstract: | In recent years, a lot of research has been done to improve the thermal climate of indoor living spaces, and machines such as air conditioners that can modify the thermal environment of indoor living areas have also been developed to aid in this effort. However, as the pace of urbanization continues to rise, the urban heat island effect increasingly manifests itself, and the temperature outside continues to rise year after year, causing people to pay growing interest to their outdoor thermal comfort and safety. The convective heat transfer coefficient is a good representation of the heat dissipation process that takes place between the human body and the outside world, it is frequently employed as the foundational parameter for evaluating outdoor thermal comfort. In contrast, there are few research on convective heat transfer coefficients in outdoor wind environments in the literature. Unlike real-world wind environments, most of this research is based on artificial environments (wind tunnels) or simulation computations, which cannot accurately reflect the variation in convective heat transfer coefficients caused by wind in an outdoor environment. Furthermore, turbulence is an important characteristic quantity of outdoor wind, and there has been little investigation into the range of tolerable values for this quantity. Because of this, the primary goal of this research is to determine the relationship between turbulence intensity, wind speed, and convective heat transfer coefficient in the conditions of outdoor wind pedestrian levels. Using a thermal manikin instead of a real human, data on skin temperature was collected during a field experiment done on campus, and the preliminary mathematical expressions on the relationship between heat transfer coefficient and turbulence intensity, and wind speed are proposed. When the wind speed is not at a high level, it is found that the strength of turbulence intensity has a stronger impact on the experimental results, and when the wind speed reaches a high level, the influence of turbulence intensity is found to be weakened. Furthermore, the convective heat transfer coefficients are not as expected from previous experiments, both at low and high turbulent intensities. This is true for both low and high turbulent intensities. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 6564.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 3.41 MB | Adobe PDF | View/Open |
Copyright Undertaking
As a bona fide Library user, I declare that:
- I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
- I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
- I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.
By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.
Please use this identifier to cite or link to this item:
https://theses.lib.polyu.edu.hk/handle/200/12145