Short-channel structures of triangular and sinu- soidal channel cross-sectional shape were examined exper- imentally to find their heat (or mass) transfer and flow friction (flow resistance) characteristics. A particular emphasis was placed on influence of the channels length (referred to its hydraulic diameter) on transport and hydro- dynamic characteristics. The transport and friction proper- ties were correlated in terms of dimensionless channel length with satisfactory accuracy. The dimensionless channel length was proved to be a key factor that determines the transport and friction coefficients. Comparison with ceramic monolith has shown possibility of using the struc- tures in automotive catalytic converters.