Design And Performance Characterisation Of A Scheffler Solar Concentrator System For Thermal Efficiency Improvement

Abstract

Meeting the ever-increasing demand for energy is a challenge, while newlineconsidering the harmful effects of conventional fuels on climate change newlineand pollution. Hence, efforts to harness clean energy are critical with newlinesolar energy which is rapidly becoming a prominent form of clean newlineenergy. Between the two methods of harnessing solar energy; newlinephotovoltaic and thermal conversion, the latter is critical for heating and newlinecooling applications of industrial processes, which form a significant newlinepercentage of the total energy usage in India. In the case of solar thermal newlineenergy conversion, Concentrated Solar Technology (CST) is newlineprogressively developing in terms of deployment. A very promising newlineCST is the Scheffler fixed focus concentrator. newlineIn the previous research, aspects such as steam generation capability, newlineefficiency performance, characterisation, efficiency improvement newlinemeasures, and the impact of environmental variables were not newlineinvestigated thoroughly. Therefore, a comprehensive investigation of newlinethese aspects was identified as an unexplored research area. newlineIn the present work, two Scheffler dish sizes were specifically chosen to newlineinvestigate the steam production rate and the concentration ratio effect newlineon performance. The complete experimental set up, involving the two newlinevi newlineScheffler dishes (with areas of 9.7 m2 (Big) and 2.7 m2 (Small)), a flat newlineplate collector, two receivers (one cylindrical and the other conical), and newlinethe appropriate instrumentation, was designed and installed at MIT, newlinePune, India. Both concentrators were assessed for performance newlineefficiency and steam generation rate by carrying out repeated newlineobservations over a number of days. The observations were then used newlinefor experimental characterisation. The same database was utilised to newlinedevelop a performance characteristic equation employing dimensional newlineanalysis. Certain parameters such as concentration ratio, wind speed, newlineand steam pressure were analysed in more detail. Regression analysis newlinewas utilised to develop the equation using MATLAB (MathWorks, newlineNatick, MA, USA). The ind