Investigation of drag reduction performance of half NACA 0009 and 0012 airfoils placed over a trailer on the flow around truck-trailer


SEYHAN M. , SARIOĞLU M.

JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY, vol.35, no.7, pp.2971-2979, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 35 Issue: 7
  • Publication Date: 2021
  • Doi Number: 10.1007/s12206-021-0620-2
  • Title of Journal : JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
  • Page Numbers: pp.2971-2979
  • Keywords: NACA 0009, NACA 0012, Drag reduction, Truck-trailer, Flow visualization, LEADING-EDGE TUBERCLES, LAMINAR SEPARATION, REYNOLDS-NUMBERS, HEAVY VEHICLES, ASPECT-RATIO, AERODYNAMICS, CAR

Abstract

The drag reduction performance of a half airfoil attached to a trailer and the roof fairing at different positions was experimentally investigated in a wind tunnel. Half airfoils have NACA 0009 and NACA 0012 cross-section and the roof fairing position is changed from -4.5 mm to +4.5 mm. Smoke wire and surface oil flow visualization were also performed to elucidate the flow characteristic around the truck-trailer with drag reduction devices. While the drag reduction rate of the truck trailer with half airfoil is up to 10% higher than that of alone truck-trailer at all Reynolds number ranges, drag reduction of the truck trailer with the half airfoil and the roof fairing was exceeded 30% as compared to the alone truck trailer. Drag coefficient results indicated that the half NACA 0009 and NACA 0012 airfoil has an almost similar trend at the zero-roof fairing position. Laminar separation bubble formation was observed on the surface of roof fairing with the help of surface oil flow visualization.