Both discrete and continuum models have been widely used to study rapid
granular flow, discrete model is accurate but computationally expensive,
whereas continuum model is computationally efficient but its accuracy is
doubtful in many situations. Here we propose a hybrid discrete-continuum method
to profit from the merits but discard the drawbacks of both discrete and
continuum models. Continuum model is used in the regions where it is valid and
discrete model is used in the regions where continuum description fails, they
are coupled via dynamical exchange of parameters in the overlap regions.
Simulation of granular channel flow demonstrates that the proposed hybrid
discrete-continuum method is nearly as accurate as discrete model, with much
less computational cost
