In this example, the tube from the previous simulations has a small clump of spherical particles attached to one of the walls. The fluid is driven by dragging one of the walls.
The IBIS file that creates the simulation in this case is:
domain 0.00 4.00 0.00 2.00 grid 8 0.0001 30000 fluid -m 0.25 -r 1.0 visual -h 128 -w 256 -n 1000 -p binary -b plat4 -y graphics -n 500 -p line -b plat2 -f particles -d 8 # # spring l -s 0 -b 0 -t 50000 line 0.0 1.75 4.0 1.75 -A 1 line 0.0 1.766 4.0 1.766 -A 2 olink 1 2 -s 20000 # line 0.0 0.25 4.0 0.25 -b 0 -s 10000 -N 3 line 0.0 0.234 4.0 0.234 -b 0 -s 10000 -N 4 blink 3 4 -s 20000 # line 0.0 0.17 4.0 0.17 -b 0 -s 10000 -N 9 line 0.0 0.154 4.0 0.154 -b 0 -s 10000 -N 10 blink 9 10 -s 20000 # spring c -s 500000 -b 0 -t 0 # circle 1.00 0.41 0.15 -n 120 -N 5 wheel 1.00 0.41 0.13 -n 120 -N 7 blink 5 7 -s 500000 # circle 1.35 0.41 0.15 -n 120 -N 6 wheel 1.35 0.41 0.13 -n 120 -N 8 blink 6 8 -s 500000 # circle 1.17 0.67 0.15 -n 120 -N 11 wheel 1.17 0.67 0.13 -n 120 -N 12 blink 11 12 -s 500000 # circle 3.00 0.41 0.15 -n 120 -N 13 wheel 3.00 0.41 0.13 -n 120 -N 14 blink 13 14 -s 500000 # link 3 5 20 -s 250000 link 3 6 20 -s 250000 link 5 6 20 -s 250000 link 5 11 20 -s 250000 link 6 11 20 -s 250000 link 3 13 20 -s 250000
The flow is driven by dragging the top wall in the domain. This is done by advancing the tether points attached to the top wall to a target location on every time step. In this example there are no sources or sinks of fluid.
c
subroutine actmov
c
c this routine performs the active motion on
c entity n. The data is passed on to afact.
c
include 'parm.inc'
include 'active.inc'
include 'domain.inc'
c
integer i,j
c
c move x coordinate of tether points for points on top wall
c
do j=1,nels
tethx(j) = tethx(j) + dlt*2.5d0
if (ibptx(j).gt.xmax) then
tethx(j) = xmin - (xmax-tethx(j))
ibptx(j) = xmin - (xmax-ibptx(j))
endif
enddo
c
return
end
A graph of nearly steady flow for this simulation is shown in the next figure.