Microstructure devices for applications in thermal and chemical process engineering

Metallic microstructure devices have been manufactured and tested for appli cations in technical applications in thermal and chemical process engineeri ng and in the laboratory. Manufacturing has been performed by micromachinin g of metal foils and diffusion bonding of a laminated foil stack, followed by welding of the microstructured core into a housing. Crossflow and counte rflow micro heat exchangers with microchannel or microcolumn structures hav e been developed for throughputs up to 7 t water/h with a heat transmission power up to 200 kW. Overall heat transfer coefficients up to 54,000 W/m(2) K have been determined with water as test fluid. Electrically driven micro structured heaters have been developed for fast and precise heating of sens itive liquids or gases. The heater has been used as an evaporator as well. Static micromixers have been developed for fast and complete mixing of reac tands. They can be utilized with parallel reactions, for example, to decrea se the yield of undesired by-products. For heterogeneously catalyzed reacti ons, several methods have been developed to coat fluid passages of already manufactured microstructure devices with thin catalytic layers.