Thermal performance improvement of a solar air heater fitted with winglet vortex generators

Chamoli, Sunil1,2; Lu, Ruixin1; Xu, Dehao1; Yu, Peng1

2018-01

10.1016/j.solener.2017.11.046

SOLAR ENERGY   影响因子和分区

0038-092X

Numerical simulations are carried out to investigate the thermal and flow characteristics of a solar air heater (SAH) embedded with winglet vortex generator (WVG) for the Reynolds number (Re) ranging from 3500 to 16,000. The geometrical parameters of WVG considered are the tip edge ratio (c/alpha) from 0 to 1 and the angle of attack (alpha) from 30 degrees to 90 degrees, respectively. Computations are based on the finite volume method coupled with the SIMPLE algorithm. The effects of WVG on the dimensionless parameters, Nusselt number (Nu), friction factor (f), Nusselt number ratio (Nu/Nu(s)), friction factor ratio (f/f(s)), and thermal enhancement factor (TEF) are discussed. Nu and f increase with the initial increase of alpha from 30 degrees to 60 degrees and then decrease with a further increase in alpha. The maximum values of Nu and f appears at alpha = 60 degrees and c/alpha = 1. The results show that the WVG with c/alpha = 0 and alpha = 30 degrees provides the best TEF in the range from 1.72 to 2.20. The internal flow behavior along with the distribution of the temperature field and streamlines is explored to explain the effect of WVG configurations on heat transfer and friction factor, respectively. The modified WVG affects the flow and temperature fields, which leads to a significant enhancement in the convective heat transfer rate.

Heat transfer Friction factor Winglet vortex generator Solar air heater Numerical simulation

SCI ; EI

英语

第一 ; 通讯

Energy & Fuels

Energy & Fuels

WOS:000423007300094

PERGAMON-ELSEVIER SCIENCE LTD

20174904496628

Air preheaters ; Angle of attack ; Angle of attack indicators ; Computer simulation ; Finite volume method ; Friction ; Geometry ; Heat convection ; Heat transfer ; Heating equipment ; Numerical models ; Nusselt number ; Reynolds number ; Solar equipment ; Solar heating ; Tribology ; Vorticity

Heat Exchange Equipment and Components:616.1 ; Fluid Flow, General:631.1 ; Heat Transfer:641.2 ; Aerodynamics, General:651.1 ; Aircraft Instruments and Equipment:652.3 ; Solar Energy and Phenomena:657.1 ; Computer Applications:723.5 ; Mathematics:921 ; Numerical Methods:921.6 ; Classical Physics; Quantum Theory; Relativity:931

ENGINEERING

Web of Science

1.Southern Univ Sci & Technol, Dept Mech & Aerosp Engn, Shenzhen 518055, Guangdong, Peoples R China
2.DIT Univ, Dept Mech Engn, Dehra Dun 248009, India

Chamoli, Sunil,Lu, Ruixin,Xu, Dehao,et al. Thermal performance improvement of a solar air heater fitted with winglet vortex generators[J]. SOLAR ENERGY,2018,159:966-983.

Chamoli, Sunil,Lu, Ruixin,Xu, Dehao,&Yu, Peng.(2018).Thermal performance improvement of a solar air heater fitted with winglet vortex generators.SOLAR ENERGY,159,966-983.

Chamoli, Sunil,et al."Thermal performance improvement of a solar air heater fitted with winglet vortex generators".SOLAR ENERGY 159(2018):966-983.