Global Stability of the Field Reversed Configuration Page: 4 of 8
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
0.8 \ E=2 S
E 0.6 S a -
0.2 -2 0 2 4 6 8
0 0.2 0.4 0.6 0.8 1 1.2
1 /- 5FIG.2: Scatter plot of the particle distribution
FIG.1: Variation of the normalized growth rate from linearized simulation of the n = 1 tilt
of n = 1 tilt mode with 1/s parameter mode with E = 7.2 and s = 0.8, racetrack
possible. In contrast, the stability properties of oblate FRCs are not affected significantly by the
thermal ion FLR effects even for small values of s (s - 1 - 2).
2. Linear Stability of n = 1 Tilt Mode
According to analytical estimates, finite Larmor radius (FLR) stabilization of the tilt mode
should occur when L* > yo , where w* is the diamagnetic frequency and yo is a characteris-
tic growth rate, from which an approximate stability condition s/E < 0.2-0.5 can be obtained.
In the previous kinetic calculations based on Vlasov-fluid dispersion functional approach and
using trial functions , a greatly reduced growth rate for s ~ 2 and complete stabilization at
s < 1.5 (E = 7.7) was obtained.
Our self-consistent hybrid simulations show that there is a reduction in the tilt mode growth
rate when s/E < 1, but no absolute stabilization has been found for s/E values as small as 0.1.
The difference between our results and the dispersion analysis results can be explained by the
deviation of the true kinetic eigenfunction from an assumed MHD-like trial function  in the
strongly kinetic regime (small s). The linear stability results for two family of equilibria with
E ~ 2 and E = 7.2 are summarized in Fig. 1, where the growth rate is shown for different
values of 1/s. Notice that y is only slightly reduced for s > 1.5 in the simulations with small
elongation E ~ 2. For the configurations with E = 7.2, there is a significant reduction in the
tilt instability growth rate at small values of s, however, no absolute stabilization has been found
even for s < 1.
One of the possible explanations of the instability existing beyond the FLR theory stability
threshold is the resonant interaction of the wave with ions for which the Doppler shifted wave
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Belova, E.V.; Jardin, S.C.; Ji, H.; Kulsrud, R.M.; Park, W. & Yamada, M. Global Stability of the Field Reversed Configuration, article, November 15, 2000; Princeton, New Jersey. (digital.library.unt.edu/ark:/67531/metadc721435/m1/4/: accessed November 14, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.