Jet impingement in a V-rib roughened solar air heater: an experimental approach

ABSTRACT

The present research article is an experimental investigation of an impinging jet solar air heater with V-patterned ribs on a modified absorber plate. The study attempts to combine active-passive jet impingement techniques focusing on varying jet parameters and variation in the arrangement of the V pattern. The experimental trials are conducted by varying parameters as follows: streamwise pitch ratio of circular jets $X_{st}/D_{hd}$ from 0.35 to 0.50, the span-wise pitch ratio of circular jets $Y_{sp}/D_{hd}$ from 0.79 to 0.94, and width ratio of V-patterned ribs w/W from 1 to 6. The geometrical parameter is kept constant, viz. angle of attack (α) = 60°, pitch ratio P/e = 10, and rib height ratio $e/D_{hd}$=0.043. The range for Reynolds number is kept between 4000 and 16,600, and solar insolation was 1000 W/m². The results indicated that jet impingement on the ribbed absorber plate enhances thermal and thermohydraulic efficiencies. The maximum reported Thermal-Hydraulic Performance in the present study was 3.301.

Graphical Abstract
2017

KEYWORDS:

• Artificial roughness
• jet impingement
• thermohydraulic efficiency
• Reynolds number
• Nusselt number

Disclosure statement

No potential conflict of interest was reported by the author(s).