Techniques for analyzing flow of a quantity in a given domain are provided. In one aspect, a method for modeling regions in a domain affected by a flow of a quantity is provided which includes the following steps. A physical representation of the domain is provided. A grid that contains a plurality of grid-points in the domain is created. Sources are identified in the domain. Given a vector field that defines a direction of flow of the quantity within the domain, a boundary value problem is defined for each of one or more of the sources identified in the domain. Each of the boundary value problems is solved numerically to obtain a solution for the boundary value problems at each of the grid-points. The boundary value problem solutions are post-processed to model the regions affected by the flow of the quantity on the physical representation of the domain.

STATEMENT OF GOVERNMENT RIGHTS
This invention was made with Government support under Contract number DE-EE0002897 awarded by Department of Energy. The Government has certain rights in this invention.