Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney
Simulations by computational fluid dynamics using Phoenics were performed for a chimney, represented by a vertical cylinder of diameter 100 m and height of 200 m, located at clearances of 14.68 m, 10 m and 5 m above ground to provide for increasingly higher inlet resistances, with a temperature-cont...
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| Format: | Article |
| Language: | English English |
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Elsevier Science
2016
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| Online Access: | https://eprints.ums.edu.my/id/eprint/21455/1/Improved%20thermal%20energy%20discharge%20rate%20from%20a%20temperature-controlled%20heating%20source%20in%20a%20natural%20draft%20chimney.pdf https://eprints.ums.edu.my/id/eprint/21455/7/Improved%20thermal%20energy%20discharge%20rate%20from%20a%20temperature-controlled%20heating%20source%20in%20a%20natural%20draft%20chimney.pdf |
| _version_ | 1825713565105913856 |
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| author | Chi-Ming Chu Md Mizanur Rahman Sivakumar Kumaresan |
| author_facet | Chi-Ming Chu Md Mizanur Rahman Sivakumar Kumaresan |
| author_sort | Chi-Ming Chu |
| collection | UMS |
| description | Simulations by computational fluid dynamics using Phoenics were performed for a chimney, represented by a vertical cylinder of diameter 100 m and height of 200 m, located at clearances of 14.68 m, 10 m and 5 m above ground to provide for increasingly higher inlet resistances, with a temperature-controlled heater near the cylinder inlet (bottom) set at a temperature of 50 °C and ambient air temperature of 30 °C in still surroundings. The simulated results, in particular the cold inflow pattern, agreed with heat flux-controlled experiments previously carried out and two earlier simulation results by other workers; in addition, draft enhancement was also achieved as in the case when cold inflow had been impeded with the heat flux-controlled experiments. The wire mesh simulated as a flow resistor was found to effectively impede cold inflow for cylinders of these arrangements. Favre-averaging was found to provide closer values to true averages in maldistributed flows and overcame the problem of area-averaging in cold inflow situations, where poor heat balances were likely experienced. By impeding cold inflow or flow reversal, the average draft flow rate and the heat discharge rate were found to have improved significantly by up to 34 per cent, on the basis of Favre-averaged heat loads for the cases examined. The analysis showed that the natural convection thermal energy discharge rate and the draft from a temperature-controlled heating source in a chimney were enhanced, contrary to the normal expectation that it would be reduced, when cold inflow is impeded by installing wire mesh at the chimney top exit. |
| first_indexed | 2024-03-06T02:58:33Z |
| format | Article |
| id | ums.eprints-21455 |
| institution | Universiti Malaysia Sabah |
| language | English English |
| last_indexed | 2024-03-06T02:58:33Z |
| publishDate | 2016 |
| publisher | Elsevier Science |
| record_format | dspace |
| spelling | ums.eprints-214552021-08-26T07:01:19Z https://eprints.ums.edu.my/id/eprint/21455/ Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney Chi-Ming Chu Md Mizanur Rahman Sivakumar Kumaresan T Technology (General) Simulations by computational fluid dynamics using Phoenics were performed for a chimney, represented by a vertical cylinder of diameter 100 m and height of 200 m, located at clearances of 14.68 m, 10 m and 5 m above ground to provide for increasingly higher inlet resistances, with a temperature-controlled heater near the cylinder inlet (bottom) set at a temperature of 50 °C and ambient air temperature of 30 °C in still surroundings. The simulated results, in particular the cold inflow pattern, agreed with heat flux-controlled experiments previously carried out and two earlier simulation results by other workers; in addition, draft enhancement was also achieved as in the case when cold inflow had been impeded with the heat flux-controlled experiments. The wire mesh simulated as a flow resistor was found to effectively impede cold inflow for cylinders of these arrangements. Favre-averaging was found to provide closer values to true averages in maldistributed flows and overcame the problem of area-averaging in cold inflow situations, where poor heat balances were likely experienced. By impeding cold inflow or flow reversal, the average draft flow rate and the heat discharge rate were found to have improved significantly by up to 34 per cent, on the basis of Favre-averaged heat loads for the cases examined. The analysis showed that the natural convection thermal energy discharge rate and the draft from a temperature-controlled heating source in a chimney were enhanced, contrary to the normal expectation that it would be reduced, when cold inflow is impeded by installing wire mesh at the chimney top exit. Elsevier Science 2016-04-05 Article PeerReviewed text en https://eprints.ums.edu.my/id/eprint/21455/1/Improved%20thermal%20energy%20discharge%20rate%20from%20a%20temperature-controlled%20heating%20source%20in%20a%20natural%20draft%20chimney.pdf text en https://eprints.ums.edu.my/id/eprint/21455/7/Improved%20thermal%20energy%20discharge%20rate%20from%20a%20temperature-controlled%20heating%20source%20in%20a%20natural%20draft%20chimney.pdf Chi-Ming Chu and Md Mizanur Rahman and Sivakumar Kumaresan (2016) Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney. Applied Thermal Engineering, 98. pp. 991-1002. ISSN 1359-4311 https://doi.org/10.1016/j.applthermaleng.2015.12.098 |
| spellingShingle | T Technology (General) Chi-Ming Chu Md Mizanur Rahman Sivakumar Kumaresan Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney |
| title | Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney |
| title_full | Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney |
| title_fullStr | Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney |
| title_full_unstemmed | Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney |
| title_short | Improved thermal energy discharge rate from a temperature-controlled heating source in a natural draft chimney |
| title_sort | improved thermal energy discharge rate from a temperature controlled heating source in a natural draft chimney |
| topic | T Technology (General) |
| url | https://eprints.ums.edu.my/id/eprint/21455/1/Improved%20thermal%20energy%20discharge%20rate%20from%20a%20temperature-controlled%20heating%20source%20in%20a%20natural%20draft%20chimney.pdf https://eprints.ums.edu.my/id/eprint/21455/7/Improved%20thermal%20energy%20discharge%20rate%20from%20a%20temperature-controlled%20heating%20source%20in%20a%20natural%20draft%20chimney.pdf |
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