Thermal performance in a pin fin-dimple/protrusion duct with different optimal objectives

• In the present study, the optimal objective effect on the thermal performance of a rectangular duct with pin fins and dimples/protrusions is introduced. Four different optimal objectives are selected (entropy generation, entransy dissipation, enerty, and volume goodness factor). The baseline k-ù turbulence model is applied to solve the governing equations. The multi-island genetic algorithm (MIGA) is used to find the optimal solution. The results indicate that the thermal performance is sensitive to the optimal objective. By using the dimple/protrusion configuration, the Nusselt number is increased remarkably in the pin-finned duct. Using the volume goodness factor as an optimal objective, the Nusselt number and friction factor reach their highest values due to the greatest strength of the horseshoe vortex. An optimal objective of enerty produces a minimal increase in the Nusselt number. A relatively low friction factor is found in the cases that use entransy dissipation and enerty as optimal objectives.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering (hsv//eng)

Keyword

Dimples

Duct flow

Optimal objectives

Pin fins

Protrusions

Thermal performance

Publication and Content Type

art (subject category)

ref (subject category)