Design with constructal theory : vascularized and distributed energy systems

Abstract

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.

In this paper we use two developments to illustrate our progress in “design with constructal theory” [1]. The first is the development of smart materials with embedded vasculatures that provide multiple functionality: volumetric cooling, selfhealing, enhanced apparent (effective) thermal conductivity, and mechanical strength. Vascularization is achieved by using tree-shaped (dendritic) flow architectures. We show that as length scales become smaller, dendritic vascularization provides dramatically superior volumetric bathing than the use of bundles of parallel microchannels. A novel dendritic architecture has trees that alternate with upside down trees. In addition to flow access to the entire volume, trees offer improved robustness in flow operation. The second development is the distributing of energy systems over a given territory. The distribution of heating is used as an example. The architecture emerges from the balancing of the losses concentrated in the production centers and the losses distributed along the conduits that distribute and collect every thing that flows on the landscape. In sum, flow architectures are derived from principle, in accordance with constructal theory, not by mimicking nature.