6 The Investigation of the Evolution of Cluster Beam …
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Fig. 6.2 Geometry representation
Table 6.2 Geometry sizes
Index
R j (m)
L j (m)
1
0.0007
0.0014
2
0.00007
0.0028
3
0.001418046
0.014
4
0.00046
0.01596
5
0.00025
0.039025
6
0.0125
0.036015
6.4.1 Geometry
The computational domain includes the axisymmetric conical supersonic micronozzle, jet flowing out into the vacuum chamber, and axisymmetric skimmer located
coaxially with the micro-nozzle at the certain distance from the micro-nozzle cut
(Fig. 6.2).
The micro-nozzle starting from the critical section has a conical shape, and the
skimmer has the shape of a hollow truncated cone connected to a hollow cylinder.
All device sizes are shown in Table 6.2.
6.4.2 Grid
The composite regular computational grid consists of quadrangular cells, is divided
into blocks, and has a condensation to the boundaries of the areas coinciding with
rigid walls (Fig. 6.3). In total, about 170 thousand design cells (790 × 210) are
present in the computational grid; 6000 cells (200 × 30) fall on the area inside the
micro-nozzle.