Delete fix_wall_maxwell.txt

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:link(lc,Section_commands.html#comm)

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fix wall/maxwell command :h3

[Syntax:]

fix ID group-ID wall/maxwell face pos temp velx vely velz keyword value ... :pre

ID, group-ID are documented in "fix"_fix.html command :ulb,l

wall/maxwell = style name of this fix command :l

one or more face/arg pairs may be appended :l

face = {xlo} or {xhi} or {ylo} or {yhi} or {zlo} or {zhi} :l

  {xlo},{ylo},{zlo} pos = EDGE or constant or variable

    EDGE = current lo edge of simulation box

    constant = number like 0.0 or -30.0 (distance units)

    variable = "equal-style variable"_variable.html like v_x or v_wiggle

    temp = wall temperature

    velx, vely, velz = wall velocity along x, y, z directions

    accom = accommodation coefficient

  {xhi},{yhi},{zhi} pos = EDGE or constant or variable

    EDGE = current hi edge of simulation box

    constant = number like 50.0 or 100.3 (distance units)

    variable = "equal-style variable"_variable.html like v_x or v_wiggle 

    temp = wall temperature 

    velx, vely, velz = wall velocity along x, y, z directions

    accom = accommodation coefficient :pre

zero or more keyword/value pairs may be appended :l

keyword = {units} :l

    {units} value = {lattice} or {box}

    {lattice} = the wall position is defined in lattice units

    {box} = the wall position is defined in simulation box units :pre

:ule

[Examples:]

fix ywalls all wall/maxwell xlo EDGE 300 0.1 0.1 0 0.8 xhi EDGE 200 0.1 0.1 0

0.8

fix ywalls all wall/maxwell xlo 300 0.1 0.1 0 ylo 300 0.1 0.1 0 0.9 units box

:pre

[Description:]

This is a stochastic wall model which is the mixture of two fixes (and two wall

models) wall/reflect and wall/diffusive, proposed by Maxwell "Maxwell"_#Maxwell.

An atom can be either fully thermalized by the wall and reflected diffusively or

reflected specularly. In this case, the accommodation coefficient (ACCOM) lying

between 0 and 1, is introduced to account for the diffusive reflection portion.

As noted, when ACCOM = 0, the reflection is purely specular and when ACCOM = 1,

the reflection is purely diffusive. The use of this stochastic model is almost

the same as wall/reflect but with five additional parameters the wall

temperature and the wall velocity along 3 directions x, y, z, and the

accommodation coefficient.

The {units} keyword determines the distance units used to define a wall position

A {box} value selects standard distance units as defined by the

"units"_units.html command, e.g. Angstroms for units = real or metal. 

A {lattice} value means the distance units are in lattice spacings. The

"lattice"_lattice.html command must have been previously used to define the

lattice spacings.

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[Restrictions:]

Due to its properties, this fix has has the same limitation as the the

wall/reflect. Any dimension (xyz) that has a wall must be non-periodic. It

shoudld not be used with rigid bodies such as those defined by a "fix rigid"

command. 

[Related commands:]

"fix wall/reflect"_fix_wall_reflect.html, "fix

"wall/diffusive"_fix_wall_diffusive.html, "fix wall/cl"_fix_wall_cl.html

[Default:] none

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:link(Maxwell) [(Maxwell)] Maxwell, J. C. (1867). "On the Dynamical Theory of

Gases". Philosophical Transactions of the Royal Society of London. 157: 49–88.