Performance enhancement of twist inserted solar collector using booster reflectors

Abstract

The heat transfer friction factor and thermal performance of a conventional flat plate solar collector are investigated experimentally using flat booster reflectors and corrugated booster reflectors in three different manners At first the experiment is conducted in the conventional solar thermal collector with flat booster reflectors called FBR solar collector using peripherally oblique-cut twisted tapes and peripherally wing-cut twisted tapes Then corrugated booster reflectors are introduced in place of flat booster reflectors and the performance of the system is analyzed using centrally finned twist Finally a comparative study is prepared in the solar thermal collector with corrugated booster reflectors using the above three twisted tapes proposed Besides for comparison typical twisted tape with twist ratio 3and 6 are also tested The water is used as the working fluid and solar radiation is the heat input to the collector The experiment is conducted under natural circulation mode Due to gradual increase and decrease in solar intensity during a day the overall observations have been divided into phase I and phase II The effective reflector area of solar collector with corrugated booster reflectors is 16 higher than the solar collector with flat booster reflectors Hence the corrugated booster reflector augments the Nusselt number around 825 over the flat booster reflector newline