Ready, get set, go

This page tells you how to get DL_MESO up and running.

How to obtain DL_MESO

• DL_MESO – mesoscale simulations (version 2.7 and above).
• DL_MESO User Manual (PDF) - Version 2.7, September 2021.

To be able to use the latest version of DL_MESO you first need to register here. Successful registration will lead to you receiving an email containing instructions on how to download the latest version of DL_MESO. Following the instructions in the email from CCP5-ADMIN should give you an unzipped directory (e.g. dl_meso).

The next step is to compile dl_meso executables. There are two main codes - one for Lattice Boltzmann Equation (LBE) simulations (DL_MESO_LBE), one for Dissipative Particle Dynamics (DPD) simulations (DL_MESO_DPD) - and a set of utilities for preparing simulations and processing their results.

If your computer has compilers, MPI implementations etc. available as loadable modules, you may need to load them in before proceeding with compilation. This may involve a command such as:

$: module load gcc7 openmpi-gcc7

to make the compilers and an MPI implementation available (e.g. the GCC 7 compiler set and OpenMPI coupled to those compilers).

Compiling DL_MESO_LBE

The LBE code in DL_MESO requires a C++ compiler. If you want to compile an executable to run on more than one core, e.g. on a high performance computing (HPC) system, you will also need an implementation of MPI. The code can also be compiled to run on multiple available threads using OpenMP by including a compiler flag.

For the single-core (serial) version of DL_MESO_LBE with OpenMP threading, starting from the folder with the dl_meso directory in a e.g. bash terminal, type the following commands (adapting if necessary for available modules/compilers):

$: cd dl_meso/WORK
$: g++ -O3 -fopenmp -o lbe.exe ../LBE/slbe.cpp

For the multiple-core (parallel) version of DL_MESO_LBE with OpenMP threading, type the following commands, adapting if necessary for specific HPC and available modules/compilers/MPI implementations:

$: cd dl_meso/WORK
$: mpicxx -O3 -fopenmp -o lbe.exe ../LBE/plbe.cpp

Successful compilation leads to the creation of the DL_MESO_LBE executable (lbe.exe) in dl_meso/WORK/.

Compiling DL_MESO_DPD

The DPD code in DL_MESO requires a Fortran compiler and GNU Make (normally pre-installed on Unix/Linux systems). If you want to compile an executable to run on more than one core, e.g. on a high performance computing (HPC) system, you will also need an implementation of MPI. The code can also be compiled to run on multiple available threads using OpenMP.

Whichever version is required, a Makefile is available in the dl_meso/DPD/makefiles directory: this needs to be copied into the working directory and invoked. For instance, if you want to compile the parallel version of DL_MESO_DPD using MPI, starting from the folder with the dl_meso directory in a e.g. bash terminal, type the following commands, adapting if necessary for specific HPC and available modules/compilers/MPI implementations:

$: cd dl_meso/WORK
$: cp ../DPD/makefiles/Makefile-MPI ./Makefile
$: make

TIP:You may wish to check the Makefile is specifying the correct Fortran compiler (with MPI wrapper if applicable) in the line starting with FC= before invoking it.

Successful compilation leads to the creation of the dl_meso_dpd executable (dpd.exe) in dl_meso/WORK/.

Compiling utilities

The utilities included with DL_MESO require Fortran and C++ compilers. Some of the utilities for DPD simulations can be made to run faster by applying OpenMP multithreading using a compiler flag.

A Makefile for the utilities (Makefile-utils) is available in the dl_meso/WORK folder. To compile them, type the following commands in a terminal:

$: cd dl_meso/WORK
$: make -f Makefile-utils

TIP:

The object (.o) and module (.mod) files resulting from compiling DL_MESO_DPD and the utilities are not required to run the code and can be safely deleted:

$: rm *.o *.mod