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Saurabh Pachauri,
Manish Dixit,
Nagendra Singh,
Nonihal Singh Dhakry,
- Assistant Professor, Department of Mechanical Engineering, Institute of Engineering and Technology, Dr. Bhimrao Ambedkar University, Khandari Campus, Agra, Uttar Pradesh, India
- Assistant Professor, Department of Mechanical Engineering, Institute of Engineering and Technology, Dr. Bhimrao Ambedkar University, Khandari Campus, Agra, Uttar Pradesh, India
- Assistant Professor, Department of Mechanical Engineering, Institute of Engineering and Technology, Dr. Bhimrao Ambedkar University, Khandari Campus, Agra, Uttar Pradesh, India
- Assistant Professor, Department of Mechanical Engineering, ACE College of Engineering and Management, Agra, Uttar Pradesh, India
Abstract
Solar water heating systems have emerged as one of the most promising renewable energy technologies for reducing dependence on conventional fossil fuels and electricity-based water heating. However, the thermal performance of compact solar water heaters is often limited by inadequate solar absorption, poor heat transfer, and thermal losses within the collector assembly. This study presents a theoretical investigation of thermal performance enhancement strategies incorporated into a compact solar photovoltaic (PV)-powered concentrating water heating system. The proposed design integrates multiple heat transfer enhancement techniques, including a spiral copper coil heat exchanger, black-coated absorber surface, reflective mirror concentrator, active water circulation using a photovoltaic-powered direct current (DC) pump, and a provision for a transparent glass cover to minimize heat losses. Each enhancement technique is examined from the perspective of solar radiation absorption, conductive heat transfer, convective heat exchange, and thermal energy retention. The influence of collector geometry, material selection, and active circulation on overall thermal performance is also discussed. Standard heat transfer equations are presented to establish the theoretical framework governing the operation of the system. The study demonstrates that integrating several passive and active thermal enhancement strategies into a compact collector design can significantly improve the utilization of available solar energy while maintaining low fabrication cost and operational simplicity. The proposed approach offers an economical and environmentally sustainable solution for domestic water heating, educational demonstrations, and small-scale renewable energy applications, while providing a foundation for future experimental performance evaluation and system optimization.
Keywords: Solar water heater, Heat transfer enhancement, Concentrating solar collector, Spiral copper coil, Renewable energy, Solar thermal system, Active water circulation
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International Journal of Energy and Thermal Applications
| Volume | 04 | |
| 02 | ||
| Received | 14/07/2026 | |
| Accepted | 03/08/2026 | |
| Published | 28/08/2026 | |
| Publication Time | 45 Days |