A novel gravity based passive solar tracking mechanism; suitable to a linear solar concentrating collector has been conceptualized, developed, simulated, analyzed and tested experimentally. Attempt has been made to minimize the tracking load and error by controlling in dripping rate or filling rate of liquid in the gravity system. The identified key influencing design parameters in the proposed mechanism are sprocket wheel radius, spring stiffness and tracking radius. Large sprocket wheel, low stiff spring and small tracking radius minimizes the tracking loads. The recommended sprocket wheel radius and tracking wheel radius are 125&nbsp;mm and 60&nbsp;mm respectively. The simulation studies are validated with the experimental results. Practically obtained collector's incidence angle is compared with the minimum required (theoretical) incidence and found a satisfactory match. The improvement in thermal efficiency of the collector with the proposed tracking mechanism has been highlighted by comparing the efficiency of intermittent tracking collector. © 2016 Elsevier Ltd

Natarajan M

Department of Thermal and Energy Engineering

School of Mechanical Engineering

Vellore Campus

Srinivas T.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Renewable Energy

In perfect tracking condition, the angle between normal to solar collector’s surface and sunbeam, known as incident angle is zero to gain maximum energy collection and efficiency. The role of collector orientation on solar geometry has been studied to increase the collection of solar radiation. In current work, the focused surface orientations are (i) horizontal (ii) tilted (iii) zenith angle tracking (iv) azimuth angle tracking and (v) dual axis tracking. Sun earth relations (solar geometry) have been solved for a day, seasons and year. Azimuth angle tracking has been suggested over a zenith angle rotation for single axis tracking developers. The zenith angle rotation is favoring only in winter season. In perfect tracking, the tilt angle should be equal to zenith angle and surface azimuth should be equal to solar azimuth angle. © 2015, Allerton Press, Inc.

Applied Solar Energy

Study on solar geometry with tracking of collector

Liquid flat plate collector (solar flat plate collector) is one of the important applications in solar thermal system. The development in solar photovoltaic is an emerging challenge for the solar thermal system. In the current work an attempt has been made to optimize the number of transparent covers and refractive index to improve the optical efficiency and thermal efficiency for the collector. Performance of the liquid flat plate collector at VIT University Vellore has been simulated numerically for January 21st at an interval of half an hour with different numbers of transparent covers (0–3) and different refractive index values ranging from 1.1 to 1.7. The formulation and solutions are developed with simple software Microsoft Office Excel to result the performance characteristics. The result shows that the efficiency of the flat plate collector increases with an increase in number of covers and decreases after an optimum number of covers. It also decreases with an increase in refractive index. The combination of optimum number (two) and lower refractive index (1.1) results improved useful heat.

Fulltext

Journal of Renewable Energy

Study on Effect of Number of Transparent Covers and Refractive Index on Performance of Solar Water Heater

Advances in Physics Theories and Applications

Performance Analysis of a Constructed Dual Axis Solar Tracker

Solar Energy

Parabolic trough collector or linear Fresnel collector? A comparison of optical features including thermal quality based on commercial solutions

Renewable and Sustainable Energy Reviews

An overview on current application of nanofluids in solar thermal collector and its challenges

Experimental and simulation studies on a novel gravity based passive tracking system for a linear solar concentrating collector

Journal	Data powered by TypesetRenewable Energy
Publisher	Data powered by TypesetElsevier BV
ISSN	0960-1481
Open Access	No