Abstract: We study bifurcation structure of the zonal jet flow the
streamfunction of which is expressed by a single spherical harmonics
on a rotating sphere. In the non-rotating case, we find that a steady
traveling wave solution arises from the zonal jet flow through Hopf
bifurcation. As the Reynolds number increases, several traveling
solutions arise only through the pitchfork bifurcations and at high
Reynolds number the bifurcating solutions become Hopf unstable. In
the rotating case, on the other hand, under the stabilizing effect of
rotation, as the absolute value of rotation rate increases, the number
of the bifurcating solutions arising from the zonal jet flow decreases
monotonically. We also carry out time integration to study unsteady
solutions at high Reynolds number and find that in the non-rotating
case the unsteady solutions are chaotic, while not in the rotating cases
calculated. This result reflects the general tendency that the rotation
stabilizes nonlinear solutions of Navier-Stokes equations.
Abstract: The Non-Rotating Adjustable Stabilizer / Directional
Solution (NAS/DS) is the imitation of a mechanical process or an
object by a directional drilling operation that causes a respond
mathematically and graphically to data and decision to choose the
best conditions compared to the previous mode.
The NAS/DS Auto Guide rotary steerable tool is undergoing final
field trials. The point-the-bit tool can use any bit, work at any
rotating speed, work with any MWD/LWD system, and there is no
pressure drop through the tool. It is a fully closed-loop system that
automatically maintains a specified curvature rate.
The Non–Rotating Adjustable stabilizer (NAS) can be controls
curvature rate by exactly positioning and run with the optimum bit,
use the most effective weight (WOB) and rotary speed (RPM) and
apply all of the available hydraulic energy to the bit. The directional
simulator allowed to specify the size of the curvature rate
performance errors of the NAS tool and the magnitude of the random
errors in the survey measurements called the Directional Solution
(DS).
The combination of these technologies (NAS/DS) will provide
smoother bore holes, reduced drilling time, reduced drilling cost and
incredible targeting precision. This simulator controls curvature rate
by precisely adjusting the radial extension of stabilizer blades on a
near bit Non-Rotating Stabilizer and control process corrects for the
secondary effects caused by formation characteristics, bit and tool
wear, and manufacturing tolerances.
Abstract: A gold coated copper rotating electrode was used to
eliminate surface oxidation effect. This study examined the effect of
electrode rotation on the ozone generation process and showed that an
ozonizer with an electrode rotating system might be a possible way to
increase ozone-synthesis efficiency. Two new phenomena appeared
during experiments with the rotating electrode. First was that ozone
concentration increased to about two times higher than that of the case
with no rotation. Second, input power and discharge area were found
to increase with the rotation speed. Both ozone concentration and
ozone production efficiency improved in the case of rotating electrode
compared to the case with a non-rotating electrode. One possible
reason for this was the increase in discharge length of
micro-discharges during electrode rotation. The rotating electrode
decreased onset voltage, while reactor capacitance increased with
rotation. Use of a rotating-type electrode allowed earlier observation
of the ozone zero phenomena compared with a non-rotating electrode
because, during rotation, the entire electrode surface was functional,
allowing nitrogen on the electrode surface to be evenly consumed.
Nitrogen demand increased with increasing rotation s