The process is also called phase-ordering dynamics, or domain growth
or coarsening, and the study of it requires tools from a number of the physical sciences.
Billon and Haudin [19-21] presented a generalized Evans approach , in which they attempt to consider position and time dependence of nucleation rate and time-dependence of domain growth rate.
The model consists of three parts: primary nucleation model, domain growth model and lamellae director model.
Effects of external forces on morphological formation are included in the nucleation model for determining the formation and spatio-temporal evolution of nuclei, as well as in the proposed envelop equation of domain growth model for determining the spherulitic growth velocity.
The proposed envelop equation of domain growth is linked with the nucleation model and the elastic curvature energy equation of the lamellar director field to perform cross-scale modeling.
In order to set up a physical morphological model of domain growth, a generalized Langevin equation  is introduced:
To derive the envelop equation for multiple domain growth, we consider a domain envelop by writing the Langevin equation for the normal velocity as
The other terms represent the surface tension and noise effects on domain growth.
Considering multiple domain growth, the nuclei origin positions, which come from the nucleation model can be represented by r(i = 1,.
i[neq]j][1 - [detla](A)], represents the domain growth and impingement kinetics.
Figure 2 presents an example of numerical simulation results of domain growth.
Thus, the domain growth model utilizes two coupled fields: a non-conserved envelop vector field of the local macroscopic growth domains and a vector field of the local mesoscopic lamellae directors.