Simple mathematical modeling and simulation to estimate solar-regeneration of a silica gel bed in a naturally ventilated vertical channel for Harare, Zimbabwe
2014 (English)In: Energy Procedia, 2014, 1733-1742 p.Conference paper (Refereed)
Passive air conditioning (humidity and temperature control) in buildings is more desirable on sustainable basis. One of the challenges of passive humidity control is regeneration of the materials applied for the purpose. This paper looks at solar regeneration of a silica gel layer (bed) for typical seasons of the year in Harare, Zimbabwe. This bed forms the primary system that is then used for drying room internal surfaces during the night. The extent of silica gel solar drying is the main attention of this investigation. Solar regeneration of a silica gel bed that forms a solar 'absorber' surface of a rectangular solar channel is investigated. Simple mathematical models are developed and subsequent spreadsheet simulations are carried out. Silica gel sorption models are from literature or estimated through curvefitting of available data. Solar radiation falling on a vertical surface at a given orientation is evaluated from the global solar radiation data using a developed simulator based on correlations obtained from literature and measured solar radiation data from the local meteorological department. For a vertical solar channel of an air gap of 20mm, and a height of 3m, silica gel is regenerated to some quite low moisture content of circa 0.06kg/kg. Comparable degree of regeneration is achieved for both seasons.
Place, publisher, year, edition, pages
2014. 1733-1742 p.
Passive humidity control, Silica gel layer (bed), Solar, Solar regeneration
IdentifiersURN: urn:nbn:se:kth:diva-167901DOI: 10.1016/j.egypro.2014.10.162ISI: 000348253201096ScopusID: 2-s2.0-84922331467OAI: oai:DiVA.org:kth-167901DiVA: diva2:818897
2013 ISES Solar World Congress, SWC 2013, 3 November 2013 through 7 November 2013
QC 201506092015-06-092015-05-222015-06-09Bibliographically approved