RheoCube .20 now released

RheoCube .20 now released

The latest developments to RheoCube simulation software have gone out to the world. With the next version already well underway, here are some of the exciting new changes arising from .20.

Fluid preprocessing
It is now possible to preprocess fluids. As with all preprocessable components, you must validate your fluid first before you can run the preprocess. This is especially useful when using SMILES strings as input to create molecular structures for fluids. In this specific case, the finished preprocess will display a message giving more information on the coarse-graining procedure, whether it was successful, and what the final representation is in terms of predefined beads.

Fluid SMILES input
Fluid preprocessing results

Additionally, for fluids with SMILES string, we have the ability to visualize the fluid’s all-atom and coarse-grained structure, as generated for the microscopic SDK force field simulations.

Visualization of a fluid molecule and its coarse graining

Key pipeline information
Validated experiments have a new tab available, named ‘Info’. Its purpose is to provide an overview of the key parameters, both from the experiment itself and from all the objects that make up the experiment.

Overview of an experiment that contains particles

This includes:

  • Duration and measurement interval, expressed in seconds and periods/strains
  • Total volume fractions of each component
  • Domain size and dx
  • Shape and deformation parameters
  • Relevant HSP spheres

Models
SMILES and SDK force field
For microscopic simulations, it is now possible to enter a SMILES string in the “Fluid” card specifying a particular molecular structure, and an automatic coarse-graining algorithm will generate a coarse-grained bead representation. The beads employ the SDK (Shinoda, DeVane, Klein) force field for the calculations between beads. The new SMILES functionality should produce significantly better behavior of surfactant self assembly.

rheocube latest version released
Blend of water (not shown) and C12EO6 forming wormlike micelles with SDK force field

Chemical transport
Fick’s law states that chemical transport follows the gradient in chemical potential on the way to the global minimum of the chemical potential. Determining chemical potential gradients in chemical simulations is a topic of current research, not only at Electric Ant Lab, but also in the wider chemical community. We have found more robust evolution toward the global minimum of the chemical potential (the so-called “binodal point”) when defining transport based on chemical potential differences between blobs. This avoids trapping at the so-called “spinodal point” when basing transport on concentration gradients. While the new implementation is not guaranteed to find the global minimum when combining three or more fluids, its performance toward capturing the full range of fluid/fluid solubilites is markedly improved over the previous release.

Particle surface field
This release improves the repulsive interactions between fluid and particles by implementing a particle surface field. Solid particles at the mesoscale are represented as connected collections of blobs. As the particles are solid, fluid should not be able to penetrate into the particle. The previous implementation of pairwise repulsive interactions between particle and fluid blobs allowed, in rare instances, fluid blobs to intrude into the particles. Now, by representing the particle surface as a smoothened many-body field, the particle surface stays well-defined even under high shear. The smoothed surface representation also provides a surface normal that is used when calculating frictional forces between particles.

Data analysis and visualization
Volume rendering widget

A new method to visualize the results of a meso simulation has been added in this release. Instead of visualizing each blob as a sphere, the “volume render” widget interpolates values of a specific blob attribute to look like a continuous volume. The color and transparency corresponds to the value of the related blob attribute.

Dashboard saving
Following the introduction of per widget presets in the previous releases, we now introduce saving the state of the complete dashboard. While you are using the dashboard, the state of the dashboard is saved at regular intervals. Then, on reloading a notebook within the same session, e.g. by pressing F5 or opening the save dashboard again, the previous state is restored. You can also save the state of the dashboard on demand and load those saved states in a later session.

These are just some of the latest highlights and milestones with RheoCube. For more information, or to understand how simulations can enhance your R&D processes, talk to one of our experts today.