The arrangement of heated porous metal structures in a gas flow is advantageous for various applications, in which an interaction of the gas with a porous metal structure, through which the gas flows, is desired. It may be, for example, a reaction of the gas with the metal, which preferably takes place at an elevated temperature, an increase in the gas temperature due to interaction with the large surface of the porous metal structure or cleaning or filtration of the gas stream, for example, removal of entrained water droplets or the transfer of such droplets into the gas phase.
Because of the good controllability of electric heaters, it is known that such heaters can be used to heat the porous metal structures. A concrete example of application, which teaches the use of an electric heater for this purpose, is known from DE 10 2007 024 563 A1. This document teaches the electric heating of the honeycomb structure of a catalytic converter, wherein the essential idea is that wall sections of the porous metal structure are heated by sending current through it.
This known approach leads to considerable problems in practice. On the one hand, the manufacture of such heated porous metal structures is associated with a relatively great effort, and, on the other hand, such systems are sensitive to vibrations, which are typically present especially in mobile applications in the area of motor vehicles, because disruption of contact and/or short circuits may occur.
USPTO Backgrounds
USPTO Backgrounds