Introduction

In the last 50 years, scientists and engineers have made incredible progress in using computer simulations to understand physical systems. This is thanks to better physics understanding, modeling techniques, numerical methods, and computing power. These simulations can help design products and materials by providing insight into how they behave. Two areas of focus are macro-scale simulations for product design and micro-scale simulations for material design. These areas traditionally work separately, but advances have been made as companies nowadays are integrating materials simulation more and more to understand how materials behave at the atomistic level.

This multi-scale simulation work can be precisely executed with the integrated Dassault Systèmes products that bring together all the required physics of simulation, across all scales, for use in innovation in product, nature, and life.

The below figure shows two different workflows, (1) that is of a standard products design workflow. However, figure (2) shows a multiscale workflow that integrates molecular simulation in the usual engineering simulation process.

Figure 1: Standard Product Simulation Design Workflow

Figure 2: Standard Product Simulation Design Workflow with Multiscale Material Simulation

Why do we need multiscale simulation?

The Materials Simulation step is ideally added to the workflow because of one main reason! The majority of materials exhibit intricate structures at the nano or microscale, which affect their behavior on the continuum scale. The objective is to create a reliable continuum model that takes into account this complexity of the micro and mesoscale. To:

1. Assists in understanding the connection between chemical and physical characteristics, and bridge chemistry to application performance.

2. Develop the appropriate material for the appropriate application.

3. Understand unexplained failure behavior.

4. Drive cost down with less experimentation.

5. Decrease time to market for new reliable products.

How to Understand Atomistic Material Behavior?

Electronic Scale - Quantum Mechanics approaches

In a multiscale modeling framework used for engineering applications, the smallest-scale problem that can be solved is the calculation of molecular orbitals and electronic states of matter. By utilizing such calculations, it is possible to gain insight into intrinsic material behavior, such as crystal elasticity, interactions of molecules with their surroundings, and chemical reactions.

Atomistic Scale- Classical Equation of Atoms Approach

Using classical potentials instead of electronic state predictions allows for the simulation of much larger systems, up to millions of atoms, which captures more of the complexity of the system's chemistry than is possible with DFT. Atoms interact with one another using a bonded or valence term if they are connected, a nonbonded interaction if they are not, or a combination of both. This simplification of the interaction between atoms makes it possible to obtain accurate results of much larger systems using less computer power and even include temperature effects in the simulation.

Mesoscale- Coarse-grained Approach

The utilization of today's high-powered supercomputers permits running simulations with explicit atom-level models on potentially millions of atoms. Yet, even with more modest atom counts, the massive volumes of data created pose obstacles when it comes to visualization and analysis, while some systems are not suited for the process. For example, in the simulation of diluted solvents, it would be a waste of resources to expend effort in computing multiple explicit solvent molecules. For the research of soft matter condensed phases such as polymer phase separation or surfactant self-assembly, a coarser level of representation is usually a practical choice that grants easy access to insights and predictions of properties from 1 to 1000 nanometers with less stress on the computer. This is often referred to as the mesoscale domain.

The following visualization illustrates the distinctions among the three approaches mentioned above and their correlation with the inputs to the finite element analysis, that is done usually on the bulk scale/ CAE step.

Figure 3: Time vs Distance in Multiscale Approaches

Materials Studio- One Software for all scales

Dassault Systèmes' BIOVIA Materials Studio® (MS) is a modelling and simulation software consisting of multiple modules for modelling different materials, examining their properties, and understanding their behavior. Simulations range from the quantum to the atomic to the mesoscopic level. The software has been widely leveraged by scientists world-wide, in the different industries.

Materials Studio Research Reference Database

With more than 40,000 references, check out this Reference Database which contains a constantly expanding collection of research papers utilizing Materials Studio software in different topics.

Conlusion

Most organizations are now following the standard simulation workflow which mainly focuses on the continuum level, however, and in order to keep in pace with the ever-growing innovation and strict material regulations, organization from various industries are now exploring the materials from the different scales (Electronic Scale, Atomic Scale, Mesoscale, and Bulk Scale).

Refrences