An uncomfortable truth about modern engineering is that there really are no easy problems left to solve. In order to meet the demands of industry, it’s no longer good enough to do a bit of computational fluid dynamics (CFD) or some stress analysis. Complex industrial problems require solutions that span a multitude of physical phenomena, which often can only be solved using simulation techniques that cross several engineering disciplines. The Multiphysics development is driven by the industrial need to further the understanding of real physical phenomena in order to develop and design safer and more efficient products, which are environmentally friendly.
Multiphysics simulation allows engineers to take their product design and explore how they’ll react to certain real-world situations in a virtual environment. Different forces and loads have traditionally been tested separately, but this approach doesn’t provide an accurate prediction when two or more affect one another.
A multiphysics simulation method accounts for any interdependencies between multiple forces to provide a more accurate prediction of part, component or machine behavior. With more and more complex machinery being designed and built, multiphysics simulation is both faster and less expensive than physical prototypes.
In computational modelling, multiphysics simulation (often shortened to simply “multiphysics”) is defined as the simultaneous simulation of different aspects of a physical system or systems and the interactions among them.
Mathematical models used in multiphysics simulations are generally a set of coupled equations. A governing equation describes a major physical mechanisms or process. Multiphysics simulations are numerically implemented with discretization methods such as the finite element method, finite difference method, or finite volume method.
Generally speaking, multiphysics simulation is much harder than that for individual aspects of the physical processes. A major classification in such systems is whether the coupling occurs in the bulk (e.g., through source terms or constitutive relations that are active in the overlapping domains of the individual components) or whether it occurs over an idealized interface that is lower dimensional or a narrow buffer zone (e.g., through boundary conditions that transmit fluxes, pressures, or displacements).
The coupling may happen between two physics models, for example,
- fluid–structure interaction (FSI) analysis (fluid flow and structural field),
- thermal-stress analysis (thermal-structure),
- magneto-structure interaction (magnetic-structure), and
- electrostatic–structural interaction;
Among three physics models, namely,
- magneto-thermal-structural coupling (electric machine),
- electric-thermal-structural coupling (Joule heating),
- high-frequency electromagnetic thermal-structural coupling (RF heating),
- harmonic-electromagnetic-thermal-fluidic coupling (induction stirring) etc.; or
coupling among four physics models
- electromagnetic-thermal-structural-fluid), for example, RF thermal probe and electric motor.
The most common occurance are coupling like fluid-structural interactions (FSI), thermal-structural, and fluid-thermal-structural, electric-thermal-structural coupling (Joule heating) analysis.
