Numerical analysis of the influence of spherical turbulence generators on heat transfer enhancement of flat plate solar air heater

Manjunath, M S and Karanth, Vasudeva K and Sharma, Yagnesh N (2017) Numerical analysis of the influence of spherical turbulence generators on heat transfer enhancement of flat plate solar air heater. Energy, 121. pp. 616-630. ISSN 0360-5442

[img] PDF
1997.pdf - Published Version
Restricted to Registered users only

Download (2MB) | Request a copy
Official URL: https://www.journals.elsevier.com/energy

Abstract

This paper presents the influence of spherical turbulence generators on thermal efficiency and thermohydraulic performance of flat plate solar air heater. The analysis is carried out for the Reynolds number range of 4000e25000. The thermal performance is investigated for various diameter (D) of sphere consisting of 5,10,15,20 and 25 mm and relative roughness pitch (P/D) of 3, 6 and 12. The simulation is carried out using solar insolation as heat input at 12 noon conditions for the global position of Manipal (74.786�E, 13.343�N) obtained through the solar load model, a feature available in the software tool used for the analysis and Discrete Ordinates radiation model is used to compute the radiation heat interactions within the computational domain. The CFD results for the base model are validated against experimental results and are found to have good agreement. The thermal efficiency is found to increase with increasing sphere diameter and reducing relative roughness pitch. The maximum average percentage increase in thermal efficiency is found to be about 23.4% as compared to the base model for D ¼ 25 mm and P/D ¼ 3. The highest increase in the Nusselt number is found to be 2.5 times higher as compared to the base model for D ¼ 25 mm and P/D ¼ 3 at Re ¼ 23560. The analysis shows that the relative roughness pitch and size of the spherical turbulator have significant influence on the thermohydraulic performance of solar air heater

Item Type: Article
Uncontrolled Keywords: Spherical turbulence generator Solar air heater Turbulator Heat transfer enhancement Thermal performance of solar air heater
Subjects: Engineering > MIT Manipal > Mechanical and Manufacturing
Depositing User: MIT Library
Date Deposited: 29 Mar 2017 04:09
Last Modified: 29 Mar 2017 04:09
URI: http://eprints.manipal.edu/id/eprint/148592

Actions (login required)

View Item View Item