System Performance of U-Tube and Heat Pipe Solar Water Heaters

K. S.  Ong; W. L.  Tong

doi:10.6180/jase.2012.15.2.02

System Performance of U-Tube and Heat Pipe Solar Water Heaters

Physics

K. S. Ong This email address is being protected from spambots. You need JavaScript enabled to view it.¹ and W. L. Tong¹

¹School of Engineering, Monash University Sunway Campus, Jalan Lagoon Selatan, 46150 Bandar Sunway, Malaysia

Received: March 22, 2012
Accepted: May 23, 2012
Publication Date: June 1, 2012

Download Citation: ||https://doi.org/10.6180/jase.2012.15.2.02

ABSTRACT

System performance of solar water heaters depend upon collector and storage tank design and sizing and weather conditions (solar radiation intensity and ambient temperature). Nocturnal reverse flow and tank insulation dictate the degree of overnight water temperature drop in the storage tank. A tropical country like Malaysia has widely fluctuating and intermittent solar radiation. It is neither practical nor feasible to conduct outdoor tests such as that proposed by International Standards. Indoor collector tests are expensive to conduct and would not provide meaningful information to the domestic or commercial end user. Outdoor system tests would be more informative to consumers who would like to compare the water temperatures that could be achieved in order to choose from the wide range of commercial products available. This paper reports the results of outdoor tests conducted on several evacuated tube solar collectors (U-tube and heat pipe types) under natural and forced convection. Although tested at different times, the long and short term test procedures employed allowed us to compare the performances of the various systems as if they were tested simultaneously side-by-side. It was found that the natural convection heat pipe system performed best among them.

Keywords: Heat Pipe, U-Tube, Solar Water Heater, Natural Convection, Forced Convection

REFERENCES

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