1990-02-01

Analysis of Wake Pattern for Reducing Aerodynamic Drag of Notchback Model 900318

Notchback models generally have more complicated flow patterns than box models. This leads to intricate infuluence of rear geometry of Notchback on aerodynamic drag. Therefore, based on understanding of wake structure, flow phenomena for reducing the drag can be analyzed.
This paper analyzes the influence of geometry of rear portion on the drag by means of 1/5 scale notchback models. For fastback models, at certain critical angle of the rear window the drag shows a sharp peak. For notchback models, it is found that some combination of the angle of rear window and the height of trunk deck shows simillar maximum in the drag.
Moreover, the flow visualization and the detailed measurements of velocity fluctuation clarify typical vortex patterns of wake, which are an arch-type vortex behind the rear window and the trailing vortex behind the trunk deck.
These vortex patterns are similar to the numerical flow patterns obtained by the direct integration of the unsteady, incompressible Navier-Stokes equations.
As a result, it is found that an effective configuration parameter on aerodynamic drag is related to wake patterns.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Drag Measurement Through Wake Analysis

840302

View Details

TECHNICAL PAPER

Evaluation of Equivalent Temperature in a Vehicle Cabin with a Numerical Thermal Manikin (Part 1): Measurement of Equivalent Temperature in a Vehicle Cabin and Development of a Numerical Thermal Manikin

2019-01-0697

View Details

TECHNICAL PAPER

The Impact of Vehicle Front End Design on AC Performance

2013-01-0859

View Details

X