Energy effectiveness of simultaneous heat and mass exchange devices
Simultaneous heat and mass exchange devices such as cooling towers, humidifiers and dehumidifiers are widely used in the power generation, desalination, air conditioning, and refrigeration industries. For design and rating of these components it is useful to define their performance by an effectiven...
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| Format: | Article |
| Language: | en_US |
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Global Digital Central
2011
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| Online Access: | http://hdl.handle.net/1721.1/65079 https://orcid.org/0000-0002-2901-0638 https://orcid.org/0000-0003-4777-1286 |
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| author | Narayan, G. Prakash Mistry, Karan Hemant Sharqawy, Mostafa H. Zubair, Syed M. Lienhard, John H. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Narayan, G. Prakash Mistry, Karan Hemant Sharqawy, Mostafa H. Zubair, Syed M. Lienhard, John H. |
| author_sort | Narayan, G. Prakash |
| collection | MIT |
| description | Simultaneous heat and mass exchange devices such as cooling towers, humidifiers and dehumidifiers are widely used in the power generation, desalination, air conditioning, and refrigeration industries. For design and rating of these components it is useful to define their performance by an effectiveness. In this paper, several different effectiveness definitions that have been used in literature are critically reviewed and an energy based effectiveness which can be applied to all types of heat and mass exchangers is defined. The validity and the limitations of the various effectiveness definitions are demonstrated by way of several examples including direct and indirect contact, parallel and counterflow heat and mass exchangers. The limiting case of a simple heat exchanger is also discussed. The importance of thermal balancing in minimizing entropy production and its implications for optimization and design of these devices is dealt with in detail. The application of the energy effectiveness to heat-exchanger-like "-NTU correlations is also examined using a detailed numerical model. |
| first_indexed | 2024-09-23T08:55:08Z |
| format | Article |
| id | mit-1721.1/65079 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T08:55:08Z |
| publishDate | 2011 |
| publisher | Global Digital Central |
| record_format | dspace |
| spelling | mit-1721.1/650792022-09-30T12:08:17Z Energy effectiveness of simultaneous heat and mass exchange devices Narayan, G. Prakash Mistry, Karan Hemant Sharqawy, Mostafa H. Zubair, Syed M. Lienhard, John H. Massachusetts Institute of Technology. Department of Mechanical Engineering Mistry, Karan Hemant Narayan, G. Prakash Mistry, Karan Hemant Sharqawy, Mostafa H. Lienhard, John H. Simultaneous heat and mass exchange devices such as cooling towers, humidifiers and dehumidifiers are widely used in the power generation, desalination, air conditioning, and refrigeration industries. For design and rating of these components it is useful to define their performance by an effectiveness. In this paper, several different effectiveness definitions that have been used in literature are critically reviewed and an energy based effectiveness which can be applied to all types of heat and mass exchangers is defined. The validity and the limitations of the various effectiveness definitions are demonstrated by way of several examples including direct and indirect contact, parallel and counterflow heat and mass exchangers. The limiting case of a simple heat exchanger is also discussed. The importance of thermal balancing in minimizing entropy production and its implications for optimization and design of these devices is dealt with in detail. The application of the energy effectiveness to heat-exchanger-like "-NTU correlations is also examined using a detailed numerical model. King Fahd University of Petroleum and Minerals 2011-08-04T14:22:09Z 2011-08-04T14:22:09Z 2010 Article http://purl.org/eprint/type/JournalArticle 2151-8629 http://hdl.handle.net/1721.1/65079 Narayan, G. P. et al. "Energy effectiveness of simultaneous heat and mass exchange devices." Frontiers in Heat and Mass Transfer (FHMT), 1, 023001 (2010)Copyright © 2010 by Global Digital Central https://orcid.org/0000-0002-2901-0638 https://orcid.org/0000-0003-4777-1286 en_US http://dx.doi.org/10.5098/hmt.v1.2.3001 Frontiers in Heat and Mass Transfer Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Global Digital Central Global Digital Central |
| spellingShingle | Narayan, G. Prakash Mistry, Karan Hemant Sharqawy, Mostafa H. Zubair, Syed M. Lienhard, John H. Energy effectiveness of simultaneous heat and mass exchange devices |
| title | Energy effectiveness of simultaneous heat and mass exchange devices |
| title_full | Energy effectiveness of simultaneous heat and mass exchange devices |
| title_fullStr | Energy effectiveness of simultaneous heat and mass exchange devices |
| title_full_unstemmed | Energy effectiveness of simultaneous heat and mass exchange devices |
| title_short | Energy effectiveness of simultaneous heat and mass exchange devices |
| title_sort | energy effectiveness of simultaneous heat and mass exchange devices |
| url | http://hdl.handle.net/1721.1/65079 https://orcid.org/0000-0002-2901-0638 https://orcid.org/0000-0003-4777-1286 |
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