A Numerical Investigation of an Artificially Roughened Solar Air Heater
Anil Singh Yadav,
Tabish Alam,
Gaurav Gupta,
Rajiv Saxena,
Naveen Kumar Gupta,
K. Viswanath Allamraju,
Rahul Kumar,
Neeraj Sharma,
Abhishek Sharma,
Utkarsh Pandey,
Yogesh Agrawal
Affiliations
Anil Singh Yadav
Mechanical Engineering Department, IES College of Technology, Bhopal 462044, Madhya Pradesh, India
Tabish Alam
CSIR-Central Building Research Institute, Roorkee 247667, Uttarakhand, India
Gaurav Gupta
School of Mechanical Engineering, Vellore Institute of Technology, Vellore 632014, Tamilnadu, India
Rajiv Saxena
Mechanical Engineering Department, Infinity Management and Engineering College, Sagar 470001, Madhya Pradesh, India
Naveen Kumar Gupta
Mechanical Engineering Department, Institute of Engineering & Technology, GLA University, Mathura 281406, Uttar Pradesh, India
K. Viswanath Allamraju
Mechanical Engineering Department, Institute of Aeronautical Engineering, Hyderabad 500043, Telangana, India
Rahul Kumar
School of Mechanical Engineering, Lovely Professional University, Phagwara 144001, Punjab, India
Neeraj Sharma
Department of Mechanical Engineering, Maharishi Markandeshwar Engineering College, Maharishi Markandeshwar (Deemed to Be University), Mullana, Ambala 133207, Haryana, India
Abhishek Sharma
Mechanical Engineering Department, Manipal University Jaipur, Jaipur 303007, Rajasthan, India
Utkarsh Pandey
Production and Industrial Engineering Department, Birla Institute of Technology, Mesra 835215, Jharkhand, India
Yogesh Agrawal
Mechanical Engineering Department, Sagar Institute of Research & Technology, Bhopal 462041, Madhya Pradesh, India
Solar air heating devices have been employed in a wide range of industrial and home applications for solar energy conversion and recovery. It is a useful technique for increasing the rate of heat transfer by artificially creating repetitive roughness on the absorbing surface in the form of semicircular ribs. A thermo-hydraulic performance analysis for a fully developed turbulent flow through rib-roughened solar air heater (SAH) is presented in this article by employing computational fluid dynamics. Both 2-dimensional geometrical modeling and numerical solutions were performed in the finite volume package ANSYS FLUENT. The renormalization-group (RNG) k-ε turbulence model was used, as it is suitable for low Reynolds number (Re) turbulent flows. A thermo-hydraulic performance analysis of an SAH was carried out for a ranging Re, 3800–18,000 (6 sets); relative roughness pitch (RRP), 5–25 (12 sets); relative roughness height (RRH), 0.03–0.06 (3 sets); and heat flux, 1000 W/m2. The numerical analysis revealed that with an RRP of 5 and an RRH of 0.06, the roughened duct produces the highest augmentation in average Nur in the order of 2.76 times that of a plain duct at an Re of 18,000. With an RRP = 10 and RRH = 0.06, the roughened duct was found to provide the most optimum thermo-hydraulic performance parameter (THPP). The THPP was determined to have a maximum value of 1.98 when the Re is equal to 15,000. It was found that semi-circular ribs which have a rib pitch = 20 mm and a rib height = 2 mm can be applied in an SAH to enhance heat transfer.
