LAUSR.org creates dashboard-style pages of related content for over 1.5 million academic articles. Sign Up to like articles & get recommendations!

A theoretical model of natural circulation flow and heat transfer within horizontal evacuated tube considering the secondary flow

Photo from wikipedia

Abstract Solar collectors with horizontal evacuated tubes are widely used to alleviate the energy crisis. This paper describes a numerical and theoretical study on a horizontal single-ended evacuated tube. A… Click to show full abstract

Abstract Solar collectors with horizontal evacuated tubes are widely used to alleviate the energy crisis. This paper describes a numerical and theoretical study on a horizontal single-ended evacuated tube. A range of validated numerical simulations were conducted to investigate the fluid flow and heat transfer within the tube. The results showed that the secondary flow had a significant influence on the natural circulation flow rate and the temperature distribution within the tube. A theoretical model accounting for the secondary flow was developed to estimate the circulation flow rate and axial temperature distribution. Based on the numerical results, correlations of the circulation flow rate and heat transfer were proposed. The circulation flow rate and heat transfer were correlated to the solar input, tank temperature and tube aspect ratio. Compared to an existing model, the developed model showed a better accuracy in predicting the circulation flow rate and temperature distribution.

Keywords: heat transfer; circulation flow; flow

Journal Title: Renewable Energy
Year Published: 2020

Link to full text (if available)


Share on Social Media:                               Sign Up to like & get
recommendations!

Related content

More Information              News              Social Media              Video              Recommended



                Click one of the above tabs to view related content.