Experimental evaluation of flat plate solar collector using nanofluids

• Published in: Energy conversion and management Vol. 134; pp. 103 - 115
• Main Authors: Verma, Sujit Kumar, Tiwari, Arun Kumar, Chauhan, Durg Singh
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 15.02.2017; Elsevier Science Ltd
• Subjects: Aluminum; Aluminum oxide; Bejan number; Carbon; carbon nanotubes; Copper; Copper oxides; cupric oxide; Energy conversion efficiency; Energy efficiency; Entropy; Entropy generation; Exergy; Exergy efficiency; Flat Plate solar collector; Flat plates; Flow rates; Fluids; Graphene; mass flow; Mass flow rate; Multi wall carbon nanotubes; Nanofluids; Nanoparticles; Parameters; Power efficiency; silica; Silicon; Silicon oxide; Silicon oxides; Solar collectors; Solar energy; Thermodynamics; Titanium; titanium dioxide; Titanium oxide; Titanium oxides; Flat Plate solar collector; Exergy efficiency; Bejan number; Energy efficiency; Entropy generation
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2016.12.037

•Solar collectors are special kind of heat exchangers.•Particle concentration is important parameter for thermal conductivity of nanofluid.•Rise of Bejan number indicates systems qualitative response.•Multi walled carbon nanotube is best performing. The present analysis focuses on a wide variety of nanofluids for evaluating performance of flat plate solar collector in terms of various parameters as well as in respect of energy and exergy efficiency. Also, based on our experimental findings on varying mass flow rate, the present investigation has been conducted with optimum particle volume concentration. Experiments indicate that for ∼0.75% particle volume concentration at a mass flow rate of 0.025kg/s, exergy efficiency for Multi walled carbon nanotube/water nanofluid is enhanced by 29.32% followed by 21.46%, 16.67%, 10.86%, 6.97% and 5.74%, respectively for Graphene/water, Copper Oxide water, Aluminum Oxide/water, Titanium oxide/water, and Silicon Oxide/water respectively instead of water as the base fluid. Entropy generation, which is a drawback, is also minimum in Multiwalled carbon nanotube/water nanofluids. Under the same thermophysical parameters, the maximum drop in entropy generation can be observed in Multiwalled carbon nanotube/water, which is 65.55%, followed by 57.89%, 48.32%, 36.84%, 24.49% and 10.04%, respectively for graphene/water, copper oxide/water, Aluminum/water, Titanium Oxide /water, and Silicon oxide /water instead of water as the base fluid. Rise of Bejan number towards unity emphasizes improved system performance in terms of efficient conversion of the available energy into useful functions. The highest rise in energy efficiency of a collector has been recorded in Multiwalled carbon nanotube/water, which is 23.47%, followed by 16.97%, 12.64%, 8.28%, 5.09% and 4.08%, respectively for graphene/water, Copper oxide/water, Aluminum oxide/water, Titanium oxide /water, and Silicon oxide/water instead of water as the base fluid.