Transport properties of the Menger sponge

The Menger sponge is a three-dimensional cube that comprises a self-similar, fractal domain and a non-fractal domain, both of which are continuous. Thus it is a useful heuristic model for natural and engineered fractal systems. For this purpose the effective transport coefficient associated with the transport properties (e.g., electrical conductivity, thermal conductivity) of the sponge is derived. Comparison is made to the Sierpinski sponge.