Technical Description of NETCELL: General Framework and Data Structure

This technical note presents a prototype of a freeway network simulation program, NETCELL, currently under development. NETCELL is based on the cell transmission model which captures the dynamic evolution of multicommodity traffic over a freeway network with three-legged junctions in a way that is consistent with the hydrodynamic theory of highway traffic. The report discusses implementation of the prototype program in detail, including cell representation for a freeway network with three- legged junctions data and file structures, inputs and outputs, and some key algorithms developed to model traffic progression in junctions. The memory and computational time requirements for the program are also estimated. An example for a small network with a single origin, two destinations and a single diverge junction is included. The prototype program developed at this stage is experimental. It is designed to test small networks. A software package with an enhanced user-interface and capable of handling large scale networks is currently under development and will be released for public use in the future.