A compact heat exchanger and method for making the same using the interior of randomly arranged interconnecting hollow spheres as a conduit for a first fluid and the exterior of same as a conduit for a second fluid of different temperature. The apparatus is constructed by fusing the points of contact between the objects of a packed cluster of objects, forming an impermeable layer on the fused objects and removing the fused objects to leave hollow shells interconnected at their points of contact. The interconnecting interiors of the hollow shells form an inner space to which fluid entry and exit ports may be provided to entry and exit manifolds. An outer interstitial space is realized by channeling the second fluid through the porosity in the cluster of shells comprised of the spaces outside the interconnected hollow shells.
Charles D. Wood;Harvey S. Benson