dc.contributor.author |
Seblany, Racha Youssef |
dc.date.accessioned |
2020-03-27T16:54:34Z |
dc.date.available |
2020-03-27T16:54:34Z |
dc.date.issued |
2018 |
dc.date.submitted |
2018 |
dc.identifier.other |
b22073061 |
dc.identifier.uri |
http://hdl.handle.net/10938/21555 |
dc.description |
Thesis. M.E. American University of Beirut. Department of Mechanical Engineering, 2018. ET:6877. |
dc.description |
Co-Advisors : Prof. Nesreen Ghaddar, PhD, Professor, Mechanical Engineering ; Prof. Kamel Abou Ghali, PhD, Professor, Mechanical Engineering ; Committee members : Prof. Fadl Moukalled, PhD, Professor, Mechanical Engineering ; Prof. Mahmoud Al-Hindi, PhD, Associate Professor, Chemical and Petroleum Engineering. |
dc.description |
Includes bibliographical references (leaves 34-38) |
dc.description.abstract |
The combined liquid desiccant membrane cooled ceiling (LDMC-C) with displacement ventilation (DV) removes humidity directly from the space. It is an effective method for providing thermal comfort and good air quality since it can operate at lower ceiling temperatures compared to conventional chilled ceiling. However, LDMC-C-DV system does not control humidity in the lower occupied zone which may lead to discomfort and health problems if humidity increases due to changes in occupancy or to high humidity in supply air. In this work, a method for humidity control is proposed where fraction of the dehumidified cool dry air adjacent to the LDMC ceiling is extracted from the exhaust stream and mixed with the DV supply air stream. The strategy reduces the moisture content of the mixed DV supply air without the need to use any other dehumidification technique in the supply duct. This leads to re-establishing of the thermal comfort conditions in the occupied zone; reducing the cooling requirements of the DV system, and resulting in energy savings. To study the system performance during transient loads, a time-dependent mathematical model of the LDMC-C system was developed and validated experimentally. The validated LDMC-C transient model was then integrated to the mixed DV space model and was applied to a case study to demonstrate its effectiveness in providing acceptable humidity and air quality in the occupied zone and to assess its energy performance. It was shown that during high latent load hours, the relative humidity dropped by an average of 8.72percent in the occupied zone within a period of 12 minutes. In addition, when mixing strategy is adopted, energy savings of 24percent were achieved compared to conventional dehumidification in the supply duct. |
dc.format.extent |
1 online resource (xii, 38 leaves) : illustrations |
dc.language.iso |
eng |
dc.subject.classification |
ET:006877 |
dc.subject.lcsh |
Displacement ventilation. |
dc.subject.lcsh |
Humidity -- Control. |
dc.subject.lcsh |
Indoor air quality. |
dc.subject.lcsh |
Drying agents. |
dc.subject.lcsh |
Porous materials. |
dc.title |
Humidity control in a space conditioned by a liquid desiccant membrane chilled ceiling with displacement ventilation system. |
dc.type |
Thesis |
dc.contributor.department |
Department of Mechanical Engineering |
dc.contributor.faculty |
Maroun Semaan Faculty of Engineering and Architecture |
dc.contributor.institution |
American University of Beirut |