Heat and mass transfer across interfaces in complex nanogeometries.

Heat and mass transfer in nanodevices depends much on the geometry due to the strong influence of curvature on interfacial properties, such as the Kapitza resistance. We present a method which combines nonequilibrium square gradient theory and nonequilibrium molecular dynamics simulations to obtain the coefficients in a curvature expansion of the interface transfer coefficients. The expansion can be used directly to describe heat and mass transfer in complex nanogeometries. As examples of complex nanogeometries, we consider an oblate spheroidal droplet, a prolate spheroidal bubble, and a toroidal bubble. Depending on the sign and magnitude of the curvature, transfer is enhanced or reduced significantly. The presented method is applicable to many types of interfaces and substances, and we expect it to contribute to the understanding and design of future nanodevices.