Geoscience Reference
In-Depth Information
Fig. 6.9
Swirl airflow (hot wake) behind down electrode (
1
). Airflow axis velocity, 10 m/s;
tangential velocity,
V
t
10
5
Pa;
P
d
30 m/s; static pressure,
P
st
150 W.
1
electrode,
2
hot wake,
3
vortex longitudinal plasmoid
Fig. 6.10
Airflow (hot wake) behind plasma formation (
2
). Straight streamlined airflow. Airflow
axis velocity, 10 m/s; static pressure,
P
st
10
5
Pa;
1
electrode,
2
plasmoid,
3
hot wake;
V
f
30 m/s;
P
HF
100 W
Comparison of results obtained in swirl flow with those obtained in non-swirl
flow (in straight streamline flow) gives the following. The typical high-speed frame
of the airflow around the plasmoid in Fig.
6.10
shows that there is a longitudinal
turbulent hot wake behind the plasmoid in this regime. So, there is a considerable
difference between this regime of straight streamline flow over the plasmoid and
the previous one (in swirl flow). Note that an aerodynamic drag of this vortex
longitudinal vortex plasmoid should be very small (because of the symmetrical
streamlines around it, as is shown in Fig.
6.9
).
There are many reports about BL motion (Barry
1980
; Grigorjev
2006
) near
airplanes and contrary wind, and it is well known that in some observations of
