Clone wiki

Simflowny / Home


Simflowny: open scientific models

Simflowny is a cloud-based open environment for scientific dynamical models, composed by a semantic Domain Specific Language and a friendly Integrated Development Environment, which automatically generates parallel code for simulation frameworks.

Currently supported scientific model paradigms are:

  • Partial Differential Equations, such as Navier-Stokes and Einstein Equations. This family allows almost arbitrary forms of evolution equations, including spatial derivatives of any order, simulated over mesh, particle species or both systems. The only restriction is that the system must be still first order in time.

Snapshots and model examples

To get a feeling of what you can do with Simflowny, you may have a glance at the snapshots.

Papers and notes

Papers on Simflowny

Papers using Simflowny

  • Large eddy simulations of magnetized mergers of neutron stars with neutrinos(2022). ResearchGate
  • Gravitational waves and kicks from the merger of unequal mass, highly compact boson stars(2022). ResearchGate
  • Universality of the Turbulent Magnetic Field in Hypermassive Neutron Stars Produced by Binary Mergers(2022). ResearchGate
  • No Evidence of Kinetic Screening in Simulations of Merging Binary Neutron Stars beyond General Relativity(2022). ResearchGate
  • Effects of High Density Phase Transitions on Neutron Star Dynamics (2021). ResearchGate
  • Turbulent magnetic-field amplification in the first 10 milliseconds after a binary neutron star merger: comparing high-resolution and large eddy simulations (2020). ResearchGate
  • General relativistic MHD large eddy simulations with gradient subgrid-scale model (2020). ResearchGate
  • Extension of the subgrid-scale gradient model for compressible magnetohydrodynamics turbulent instabilities (2019). Physics of Fluids
  • Towards fidelity and scalability in non-vacuum mergers (2020). ResearchGate
  • Gradient sub-grid-scale model for relativistic MHD Large Eddy Simulations(2019). ResearchGate
  • A Simflowny-based high-performance 3D code for the generalized induction equation(2018). ResearchGate
  • Gravitational waves from dark boson star binary mergers(2018). ResearchGate
  • A Simflowny-based finite-difference code for high-performance computing in Relativity(2018). ResearchGate

Latest codes generated using Simflowny

  • MHDuet LES Leakage: code to evolve Einstein equations coupled with MHD. It incorporates a realistic tabulated Equation of State, neutrino transport using the leakage scheme and Large Eddy Simulations techniques. Download the code


  • Numerical schemes included in Simflowny. PDF

Getting started

In order to set up Simflowny, there are two options:

Install Docker Images

Docker is a popular container platform. Containers allow to package software in a format that can run without dependency problems on any hardware that supports the container platform. This way, the Docker image of Simflowny can be deployed with no effort.

Install Docker and follow the instructions in the Simflowny Docker Wiki to get the Simflowny containers. If you are new to Docker it may take about an hour to get acquainted with it, install it, obtain the Simflowny containers, and get Simflowny up and running. If you already know Docker, this should take you less than 10 minutes.

Beside using Docker to run Simflowny, you may want to execute the generated code outside Docker (i.e. your local machine or a cluster). In that case, SAMRAI may be installed properly in the machine going to run the simulations. To do so, follow the instructions of step 2 from next chapter, and install, if not already installed, HDF5, OpenMPI, Silo, and SAMRAI.

Compile the source code

This option is more complex, and not recommended unless you have a specific reason for doing. Unless you are an expert Linux user, it may easily take days to get the job done.

To compile Simflowny:

  1. Obtain the source code, available at, git clone
  2. Compile the code following the guidelines in the Compilation document.
  3. Install Simflowny accordingly to the Installation and basic operation documentation.

First steps

Some tutorials are provided for beginners. Please visit Tutorials for a first introduction to Simflowny.

User guide

The User guide fully covers all Simflowny's functionality.

SimML Reference

SimML, Simulation Markup Language, is a set of tags used in Simflowny to describe algorithms within a Simulation domain for Partial Differential Equations. The language is integrated in Simflowny and, in most cases, self-descriptive. However, there is a detailed description of its usage in SimML reference.

YAML Reference

Simflowny integrate a tool to export and import YAML based documents. YAML is a human-readable data-serialization language. Using a text editor is a friendly way to modify Simflowny documents. See the External YAML edition section on Document Management section for more detail.

AsciiMath Reference

Mathematical expressions in Simflowny are introduced using a restricted set of AsciiMath. The list of available terms can be checked in AsciiMath reference.