USER-MESO

_USERMESO is a GPU-accelerated package of LAMMPS \cite{plimpton1995lammps} for mesoscopic modelling using Dissipative Particle Dynamics and Smoothed Particle Hydrodyanmics. The code achieves tremendous speedup over the CPU code, and also exhibits good scalability.

Existing LAMMPS users can follow the quick start guide to obtain and set up USER-MESO.

As a LAMMPS package, its usage pattern follows that of the trunk code. It is shipped with a complete collection of atom styles, fix styles, pair styles, bonded interaction styles and a new integrator style.

\subsection{Quick Start Guide}

\begin{enumerate}

\item Download the source code from  or \texttt{http://www.cfm.brown.edu/repo/release/USER-MESO/}

\end{enumerate}

\subsection{Step-by-step setup}

\subsection{Atom Styles}

\subsubsection{\STYLE{dpd/atomic/meso}}

The \STYLE{dpd/atomic/meso} style is derived from the \STYLE{atomic} style and shares the same data file format.

Usage:

\begin{lstlisting} atom_style dpd/atomic/meso

suffix meso atom_style dpd/atomic \end{lstlisting}

Each atom carries the following attributes:

\begin{tabular}[center]{ccc} name & type & remark
\midrule x & double[3] & coordinate
v & double[3] & velocity
f & double[3] & force
tag & int &
type & int &
image & int &
mask & int &
\end{tabular}

\subsubsection{\STYLE{dpd/bond/meso}}

The \STYLE{dpd/bond/meso} style is derived from the \STYLE{bond} style and shares the same data file format. Each atom carries the following attributes:

\begin{tabular}[center]{ccc} name & type & remark
\midrule x & double[3] & coordinate
v & double[3] & velocity
f & double[3] & force
tag & int &
type & int &
image & int &
mask & int &
molecule & int & host molecule id
\end{tabular}

% as well as the per-atom topology information:
% \begin{tabular}[center]{ccc} % name & type & remark
% \midrule % nspecial & int[3] & number of special neighbors
% special & int[?] & special neighbors
% num\_bond & int & number of bonds
% bond\_type & int[?] & type of each bond
% bond\_atom & int[?] & tag of the bonding atom % \end{tabular}

\subsubsection{\STYLE{dpd/angle/meso}}

The \STYLE{dpd/angle/meso} style is derived from the \STYLE{angle} style and shares the same data file format. Each atom carries the following attributes:

\subsubsection{\STYLE{edpd/atomic/meso}}

The \STYLE{edpd/atomic/meso} style is an extension of the \STYLE{dpd/atomic/meso} style. One more column for the particle initial temperature is required for the ATOMS section of the input data file. Each atom carries the following attributes:

\begin{tabular}[center]{ccc} name & type & remark
\midrule x & double[3] & coordinate
v & double[3] & velocity
f & double[3] & force
T & double & temperature
Q & double & heat
tag & int &
type & int &
image & int &
mask & int &
\end{tabular}

\subsection{Bond Styles}

\subsubsection*{\STYLE{fene/meso}}

\subsubsection*{\STYLE{harmonic/meso}}

\subsection{Angle Styles}

\subsubsection*{\STYLE{harmonic/meso}}

\subsection{Fix Style}

\subsubsection*{\STYLE{nve/meso}}

\subsubsection*{\STYLE{opt/meso}}

\subsubsection*{\STYLE{plane/meso}}

\subsubsection*{\STYLE{pois/meso}}

\subsubsection*{\STYLE{vprof/meso}}

\subsubsection*{\STYLE{wall/meso}}