D-Claw

D-Claw is a software library for the simulation of grain-liquid mixtures flowing over spatially variable topography. In the limit of zero grain concentration D-Claw reduces to a shallow-water flow model, and in the limit of no intergranular liquid it reduces to a dry granular flow model. D-Claw builds on clawpack, is written in Fortran, and has a python wrapper. The code is hosted on code.usgs.gov and mirrored on github.

Tip

We encourage all users of D-Claw to study the derivation of the governing equations provided by Iverson and George (2014). Understanding the equations is necessary to grasp what the model means and interpret results.

D-Claw is supported on Linux/Unix only.

Using the documentation

The documentation contains multiple elements. Most users should start with the background and theory pages, which provide an introduction to what D-Claw is and what equations it solves. Should a user find that they want to install and use D-Claw themselves, they can refer to the installation instructions. A few example applications are provided.

Each application of D-Claw is specified through a parameter input file called setrun.py. This file includes information about the simulation domain, the initial conditions, and constants (e.g., the fluid and solid densities). Many parameters in setrun are inherited from clawpack and a user should expect to read the clawpack documentation to fully understand all options. This page provides a template setrun.py. This template includes extensive comments that describe the nature and format of D-Claw specific parameters.

D-Claw has a data model written in python and a set of utility functions that assist with use of clawpack’s visclaw tools. Refer to the API for the documentation of these python tools. Most users will find the setrun.py page a more usable description of the D-Claw data model than the API documentation.

Warning

D-Claw is scientific software. A user should expect to gain a high-level of understanding by reading the documentation. For detailed understanding, a user should expect to read the source code. Additionally, some elements of D-Claw are experimental and may change.

D-Claw has been used in many scientific publications. If you use D-Claw in a publication, cite as below and send us a message so we can update the bibliography.

Citation

If you use D-Claw in a publication, cite it as follows:

George, D.L., Barnhart, K.R., and Iverson, R.M., 2025,
D-Claw - A library for simulation of granular-fluid flows,
version 1.0.0: U.S. Geological Survey software release,
https://doi.org/10.5066/P13GUXUT.

Bibtex:

@misc{george_2025,
        title = {D-Claw - A library for simulation of
                granular-fluid flows, version 1.0.0},
        author = {George, D.L. and
                  Barnhart, K.R. and
                  Iverson, R.M.},
        url = {https://code.usgs.gov/claw/dclaw},
        year = {2025},
        doi = {10.5066/P13GUXUT}
    }

References

Iverson, R.M., and George, D.L., 2014, A depth-averaged debris-flow model that includes the effects of evolving dilatancy—I. Physical basis: Proceedings of the Royal Society of London. Series A, v. 470, no. 2170, p. 20130819, https://doi.org/10.1098/rspa.2013.0819.