Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems
Flat-plate heat exchangers are examined for use as dehumidifiers in humidification–dehumidification (HDH) desalination systems. The temperature and humidity ratio differences that drive mass transfer are considerably higher than in air-conditioning systems, making current air-conditioning dehumidifi...
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| Format: | Article |
| Language: | en_US |
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Taylor & Francis
2014
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| Online Access: | http://hdl.handle.net/1721.1/86323 https://orcid.org/0000-0002-2901-0638 |
| _version_ | 1826213957122129920 |
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| author | Sievers, Martin Lienhard, John H. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Sievers, Martin Lienhard, John H. |
| author_sort | Sievers, Martin |
| collection | MIT |
| description | Flat-plate heat exchangers are examined for use as dehumidifiers in humidification–dehumidification (HDH) desalination systems. The temperature and humidity ratio differences that drive mass transfer are considerably higher than in air-conditioning systems, making current air-conditioning dehumidifier designs and design software ill-suited to HDH desalination applications. In this work a numerical dehumidifier model is developed and validated against experimental data. The model uses a logarithmic mass transfer driving force and an accurate Lewis number. The heat exchanger is subdivided into many cells for high accuracy. The Ackermann correction takes into account the effect of noncondensable gases on heat transfer during condensation. The influence of various heat exchanger design parameters is thoroughly investigated and suitable geometries are identified. Among others, the relationship between heat flow, pressure drop, and heat transfer area is shown. The thermal resistance of the condensate layer is negligible for the investigated geometries and operating point. A particle-embedded polymer as a flat-plate heat exchanger material for seawater operation substantially improves the heat flux relative to pure polymers and approaches the performance of titanium alloys. Thus, the use of particle-embedded polymers is recommended. The dehumidifier model can be applied in design and optimization of HDH desalination systems. |
| first_indexed | 2024-09-23T15:57:32Z |
| format | Article |
| id | mit-1721.1/86323 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:57:32Z |
| publishDate | 2014 |
| publisher | Taylor & Francis |
| record_format | dspace |
| spelling | mit-1721.1/863232022-09-29T17:17:03Z Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems Sievers, Martin Lienhard, John H. Massachusetts Institute of Technology. Department of Mechanical Engineering Lienhard, John H. Sievers, Martin Lienhard, John H. Flat-plate heat exchangers are examined for use as dehumidifiers in humidification–dehumidification (HDH) desalination systems. The temperature and humidity ratio differences that drive mass transfer are considerably higher than in air-conditioning systems, making current air-conditioning dehumidifier designs and design software ill-suited to HDH desalination applications. In this work a numerical dehumidifier model is developed and validated against experimental data. The model uses a logarithmic mass transfer driving force and an accurate Lewis number. The heat exchanger is subdivided into many cells for high accuracy. The Ackermann correction takes into account the effect of noncondensable gases on heat transfer during condensation. The influence of various heat exchanger design parameters is thoroughly investigated and suitable geometries are identified. Among others, the relationship between heat flow, pressure drop, and heat transfer area is shown. The thermal resistance of the condensate layer is negligible for the investigated geometries and operating point. A particle-embedded polymer as a flat-plate heat exchanger material for seawater operation substantially improves the heat flux relative to pure polymers and approaches the performance of titanium alloys. Thus, the use of particle-embedded polymers is recommended. The dehumidifier model can be applied in design and optimization of HDH desalination systems. Center for Clean Water and Clean Energy at MIT and KFUPM 2014-05-01T15:02:46Z 2014-05-01T15:02:46Z 2013-01 Article http://purl.org/eprint/type/JournalArticle 0145-7632 1521-0537 http://hdl.handle.net/1721.1/86323 Sievers, Martin, and John H. Lienhard. “Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems.” Heat Transfer Engineering 34, no. 7 (January 2013): 543–561. https://orcid.org/0000-0002-2901-0638 en_US http://dx.doi.org/10.1080/01457632.2013.730355 Heat Transfer Engineering Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Taylor & Francis Prof. Lienhard via Angie Locknar |
| spellingShingle | Sievers, Martin Lienhard, John H. Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems |
| title | Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems |
| title_full | Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems |
| title_fullStr | Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems |
| title_full_unstemmed | Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems |
| title_short | Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems |
| title_sort | design of flat plate dehumidifiers for humidification dehumidification desalination systems |
| url | http://hdl.handle.net/1721.1/86323 https://orcid.org/0000-0002-2901-0638 |
| work_keys_str_mv | AT sieversmartin designofflatplatedehumidifiersforhumidificationdehumidificationdesalinationsystems AT lienhardjohnh designofflatplatedehumidifiersforhumidificationdehumidificationdesalinationsystems |