1989 年 9 巻 34 号 p. 161-164
The Cross flow patterns, the total pressure losses, the vorticity and drag distributions of the wakes of 1/5 car models are visualized by combining three 5-hole picot tubes and a traverser in a wind tunnel. Three, passenger car shapes, an original one, the one with a reduced rear window angle, and the one with a rear spoiler, are examined and the wake data are obtained in the cross section at a half car length downstream from the car rear end. These data are calculated to evaluate vorticities, drag values, and so on and are presented as color contour maps.
The results show that in the case with the spoiler the vortices generated from rear pillars don't become clear and rather rotate in reverse, and the reduced rear window angle weakens the vorticity up to half of the original value. Using the drag distribution maps, we will be able to find out the body shapes which generate large drags.