Analysis of thermal performance characteristics in variable header solar water heating system by a swirling effect of twisted tapes

ABSTRACT

This present study experimentally investigates the hydrothermal performance of a variable header solar water heating system inserted with helix twists (HT) and helix twist with square-cut perforated (HTSCP). Experiments have been conducted between variable header inserted with simple helix and HTSCP with the Reynolds number range from 190 to 1245. From the experimentation, the Nusselt number, friction factor, and thermal performance factor for the twist ratios Y = 3and Y = 6 have been calculated. In general, the overall thermal performance of a solar water heater has been augmented by increasing the mass flow rate, this is achieved from commencing to end providing a uniform flow in all riser tubes by introducing variable header. The experiments have been performed for the ratio of Y = 3 and Y = 6 with square cut of depth ratio (DR) and width ratio (WR) of 0.27. The performance comparison between the HTSCP with the simple helix twists (HT) and plain tube collector proved that the HTSCP-3 significantly performs superior. The HTSCP-3 attained 2.46% higher Nusselt number than the other twists HT-3, HT-6, and HTSCP-6.

KEYWORDS:

• Depth and width ratio
• friction factor
• helix twist with square-cut perforated
• Nusselt number
• variable header

Acknowledgments

The authors gratefully acknowledge the financial support by the Department of Science and Technology (DST), Ministry of Science and Technology, Government of India (SR/FTP/ETA-071/2009).

Additional information

Funding

This work was supported by the Department of Science and Technology (DST), Government of India [SR/FTP/ETA-071/2009].

Notes on contributors

Selvam Thulasi

Selvam Thulasi is working as an Assistant Professor in the Department of Mechanical Engineering at University College of Engineering, Thirukkuvalai which is a constituent College of Anna University ::Chennai, Tamilnadu,  India. He has more than 20 years of teaching experience in Engineering Colleges. He has published 8 research papers in national and International journals. Also, he has presented number of papers in national and international conferences. He is an active researcher in the field of Renewable Energy and biomass gasification .He registered one patent in solar water heater.

Subramanian Jaisankar

Subramanian Jaisankar is working more than 20 years in Academic Field. He has fabricated various solar equipment such as solar water heater, solar cooker, solar distillation etc. He published more than 40 research papers in science direct publications. He presented more number of papers in National and International conference. He is an active researcher and registered more number of patents in Intellectual Property Rights(IPR). He is the author of more than 5 books related to Renewable energy. He received research fund from DST Govt.of India.