Confinement Force Parameters

Sometimes, we want to simulate particles under a confinement. We may introduce such confinement (which has no hydrodynamic interaction but only mechanical force on the particles) by the parameter ``confinement.'' Details of the models are described in §3.5.

	confinement : list in the following form;
	for spherical confinement,
	(define confinement '(
	  10.0 ;; LJ parameter epsilon in kT (so this is dimensionless value)
	  1.0  ;; LJ parameter r0 in "length" (so this is dimensionless value)
	  "sphere"
	  10.0 ;; radius of the cavity at (0, 0, 0)
	))
	or spherical confinement with a hole,
	(define confinement '(
	  10.0 ;; LJ parameter epsilon in kT (so this is dimensionless value)
	  1.0  ;; LJ parameter r0 in "length" (so this is dimensionless value)
	  "sphere+hole"
	  10.0 ;; radius of the cavity at (0, 0, 0)
	  1.0  ;; radius of the hole at (0, 0, 1) direction
	))
	for cylindrical confinement,
	(define confinement '(
	  10.0 ;; LJ parameter epsilon in kT (so this is dimensionless value)
	  1.0  ;; LJ parameter r0 in "length" (so this is dimensionless value)
	  "cylinder" ;; the cylinder center goes through (0,0,0) and (x,y,z)
	  10.0       ;; radius of the cylinder
	  1.0  0.0  0.0 ;; direction vector (x, y, z) of the cylinder
	))
	for dumbbell confinement,
	(define confinement '(
	  10.0 ;; LJ parameter epsilon in kT (so this is dimensionless value)
	  1.0  ;; LJ parameter r0 in "length" (so this is dimensionless value)
	  "dumbbell" ;; the origin is at the center of the cylinder
	  10.0       ;; left cavity radius centered at (center1, 0, 0)
	  10.0       ;; right cavity radius centered at (center2, 0, 0)
	  2.0        ;; length of the cylinder
	  1.0        ;; cylinder radius
	))
	for 2D hexagonal confinement with cylinder pipe,
	(define confinement '(
	  10.0 ;; LJ parameter epsilon in kT (so this is dimensionless value)
	  1.0  ;; LJ parameter r0 in "length" (so this is dimensionless value)
	  "hex2d"
	  10.0    ;; cavity radius
	  1.0     ;; cylinder radius
	  12.0    ;; lattice spacing
	))
	for porous media (outside of the 3D hexagonal particle array)
	(define confinement '(
	  10.0 ;; LJ parameter epsilon in kT (so this is dimensionless value)
	  1.0  ;; LJ parameter r0 in "length" (so this is dimensionless value)
	  "porous"
	  10.0    ;; particle radius
	  20.0    ;; lattice spacing in x (2R for touching case)
	))