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Abstract The majority of power consumption nowadays goes to heating. Global warming, air and water pollution caused by burning fossil fuel for heating encourage researchers and engineers to focus more on renewable energy. The solar system is one of Earth’s primary sources of clean power. Apart from photovoltaic panels and their effectiveness of power generation contribution, solar heaters are primarily used in different applications to recover heating needs in residential and commercial buildings. This paper focuses on an experimental study to generate heat by a solar system using metallic strips immersed in cement inside a solar vacuum tube. Heat can be transferred from inside the tube to the outside using metallic strips with high conductivity. Then, the metallic strips can be used as a heater to heat water or air in an isolated tank by direct contact between the hot strips and the fluid. In order to keep the system providing heat after the absence of sun’s rays, cement is used in this experiment as a heat repository.
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Numerical Investigation of the Effect of the Inclusion of Turbulators in an Evacuated Tube Solar Collector Air Heat Exchanger
Abstract Homes relying on traditional heating systems such as furnaces, stoves, boilers, and similar mechanisms typically have a common requirement: the use of fossil fuels. Since fossil fuel prices are prone to fluctuations, it is crucial to explore alternative options. In the ongoing transition towards more sustainable solutions, solar energy emerges as an environmentally friendly choice due to its renewable nature. A pivotal device in harnessing solar energy for heating purposes is the solar air heater. This study presents a numerical analysis conducted using the CFD simulation software ANSYS, focusing on the performance characteristics of a pumpless solar room air heater that incorporates sectioning. The aim was to optimize the dimensions, specifically the pitch or distance between the turbulator features, and predict the heat exchanger’s thermal performance by measuring the associated head loss. To validate their findings, the researchers compared the predicted results from the CFD simulation with the calculated results using an Excel solver. Throughout the calculations, the impact of design variations (sectioning the pipe at different lengths relative to head loss) and the Reynolds number on stream aerodynamics and heat exchange processes were considered. The findings revealed a linear relationship between temperature and distance between the turbulators, with the heat-transfer measurements increasing alongside this distance.
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- Award ID(s):
- 1914751
- PAR ID:
- 10529373
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- ISBN:
- 978-0-7918-8764-6
- Format(s):
- Medium: X
- Location:
- New Orleans, Louisiana, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1115/IMECE2023-113952
