title: Environmental dust effects on aluminum surfaces in humid air ambient.
abstract: Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems.
authors.affiliation: Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.|Center of Research Excellence in Renewable Energy (CoRE-RE), King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
authors.forename: Bekir Sami
authors.initials: BS
authors.lastname: Yilbas
authors.affiliation: Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
authors.forename: Ghassan
authors.initials: G
authors.lastname: Hassan
authors.affiliation: Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
authors.forename: Haider
authors.initials: H
authors.lastname: Ali
authors.affiliation: Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
authors.forename: Nasser
authors.initials: N
authors.lastname: Al-Aqeeli
mesh_terms: D000388:Air; D000535:Aluminum / Q000737:chemistry*; D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring; D017276:Friction; D006813:Humidity; D018625:Microscopy, Atomic Force; D012996:Solutions; D013054:Spectrophotometry, Atomic; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: D004391:Dust; D012996:Solutions; D000535:Aluminum