Macro-study on Hard Anodised Aluminium Oxide (HAAO) Coated Solar Receivers
This paper is discussing development of Hard Anodized Aluminium Oxide (HAAO) coated Solar Receivers with varying degree of surface roughness and finishing of HAAO coatings for comparative analysis. It is found that for lower DNI, roughness Ra < 1.8 μm does not adversely impact much on HAAO coating thermal behaviour, but the dark black polished coating may perform better then greyish unpolished surface, therefore high thickness of HAAO coating is desirable >150 μm using 1000 A rating rectifier (which is limited to 50–60 μm in presented experiment with 400 A rectifier) for further textural developments. Also, their stability at maximum temperature of the focal area of solar concentrators is ~660 °C. HAAO coatings perform better under toughened glass and expected to improve further under vacuum and submerged under water.
KeywordsCoating Anodized alumina Receivers Absorption Emission
Authors are thankful to the Administrative/Managerial Authorities and Faculties of IIT Delhi, MNRE-NISE, WRST, Prajapita Brahmakumaris Ishwariya Vishwa Vidhyalaya, IIT Jodhpur, Hindalco, Kiran Cookware Industries, IGSTPP/APCPL NETRA and PMI of NTPC Limited, TERI, BHEL, Thermax Limited, HCL and SPS University Udaipur for extending their Cooperation and Coordination in the study work presented and in continuation further.
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