in mikrostrukturtechnik and brennstoffzellensystem evaporator

摘要

The invention relates to a device (40) produced using microstructure technology, for passing media. The device (40) is particularly suitable for evaporating liquid media and has a layered structure comprising at least one first layer (41), which has a number of microchannels (42) through which the medium to be evaporated flows, and at least one second layer (50), which has a number of microchannels (51) and through which a heat carrier medium flows. Said microchannels (42; 51) each have an inlet opening (43; 52) and an outlet opening (44; 53). The invention provides that the outlet openings (44) of the microchannels (42) for the medium to be evaporated are smaller in surface terms and/or have a diametrically different shape to their inlet openings, in order to achieve satisfactory evaporation of the liquid medium. This causes the pressure of the liquid medium in the microchannels (42) to increase so that overheated, still liquid medium is abruptly transformed from its liquid state to a vaporous state after leaving the outlet openings (44) with the smaller surface area. The microchannels may advantageously have a surface structure that promotes turbulence, tuning the laminar flows into turbulent flows. The inventive device can be advantageously used in a device for producing/processing a fuel for a fuel cell system.