Dynaflow, Inc. software

2DynaFS is a computer program for studying bubble dynamics in situations for which the assumption of axisymmetry can be made. This program can handle the dynamics of single or multiple bubbles in an infinite liquid medium, near a free surface, near a “globule” or a “cell”, near an axisymmetric rigid and responding body, near a finite plate, and near an infinite wall (i.e. in a half-space). The following physical effects can be included in the analysis;

DynaSim is a user-friendly ship dynamics simulator that incorporates Systems Identification Techniques to determine ship maneuvering characteristics. Once these parameters are known the simulator can accurately reproduce ship motion in the presence of waves, wind, currents, and obstacles or other ships. Multi-threading enables simultaneous simulation of multiple ships. The initial efforts to develop the technology were funded by Small Business Innovation Research (SBIR) awards from the National Science Foundation the Department of Defense (see the presentation on that site: Virtual Showcase) and The National Oceanic and Atmospheric Administration.

2DFlow is a Microsoft Windows based program for visualizing flows induced by distributions of vortices, dipoles, and sources. 2DFlow graphically illustrates the use of potential flow theory and has the capability to simulate a wide range of flow problems. Designed for the educational market, 2DFlow quickly produces graphic representations of many classic fluid dynamics problems which makes it very useful for student comprehension.

3DynaFS-Bem is a general-purpose simulation tool for nonlinear dynamics of 3D free surface flows and their interactions with submerged or floating structures.

The 3DynaFS © viscous module solves the incompressible Navier-Stokes equations using an artificial compressibility method. The solution procedure can be marched in pseudo-time to reach a steady-state solution or can use a dual time-stepping scheme to obtain a time-dependent solution. The code uses a first-order Euler implicit time-difference scheme, a third-order accurate flux-difference upwind splitting scheme for convection terms, and a second-order central differencing for the viscous terms.

3DynaFS-Comp - The 3DynaFS compressible flow module solves the Euler equations using a 2nd order Godunov-type method to capture accurately the location of discontinuities such as shock waves and contact surfaces. The code uses a Level Set method and a mixed cell algorithm to simulate multi-phase and multi-material flows. A general Equation of State is used for describing various fluids and fluid like solids. This module is also capable of simulating pressure wave propagation through bubbly media including shock waves, large liquid/gas interface deformations and cavitation induced by expansion waves .

3DynaFS-Fsi is the fluid structure interaction module of 3DynaFS allowing the fluid modules to interact with a structure code through a coupler interface using either MPI or a file passing scheme. 3DynaFS-Fsi currently couples the 3DynaFS-Bem module with a six-degrees of freedom rigid body motion solver or with existing structure codes including Dyna3D1 developed by Laurence Livermore National Laboratories, SALINAS2 developed by Sandia National Laboratories , and DLEARN3, a public domain linear static and dynamic finite element analysis program.The six-degree of freedom rigid body motion solver is included in the FSI module, while the user can procure/ provide the structure code if solving a deformable structure problem is desired. The coupler interface routines are provided with 3DynaFS-Fsi and enable the user to integrate with own structure code to communicate with the 3DynaFS-Bem module.

3DynaFS-Dsm is a module to simulate complex flows involving separation areas and particle tracking dynamics including bubbly flow. This involves a Vortex Element Method to simulate shear layers and a Discrete Bubble Module and Discrete Particle Module to track bubble dynamics and particle trajectories and their interactions.

Scientists and engineers at Dynaflow Inc. faced with the complexity and limitations of existing contour and vector plotting programs developed their own easy to use software package for visualizing data: DF_Contour.

3DynaPL, a three dimensional plotting package available for Windows OS. It enables the user to view 3D wire frame and color contour plots of objects. The 3D object can be manipulated, rotated, zoomed, and triangular elements of the shape can be shaded in color representing the amplitude of a selected quantity, such as velocity, pressure, ...etc.