[1] For example, simultaneous simulation of the physical stress on an object, the temperature distribution of the object and the thermal expansion which leads to the variation of the stress and temperature distributions would be considered a multiphysics simulation.
[3] As an interdisciplinary field, multiphysics simulation can span many science and engineering disciplines.
[5] Generally speaking, multiphysics simulation is much harder than that for individual aspects of the physical processes.
The main extra issue is how to integrate the multiple aspects of the processes with proper handling of the interactions among them.
Such issue becomes quite difficult when different types numerical methods are used for the simulations of individual physical aspects.