Microstructure devices for efficient heat transfer

Abstract

Microstructure devices provide unique properties with regard to heat and mass transfer. Due to the tremendously high surface-to-volume ratio they are very well suited for many thermal and chemical processes in which large amount of heat has to be transferred. Metal microstructure devices also provide very high stability against high pressure, combined with an adjustable mass flow range of up to several thousand kg of liquid per hour and per passage, depending on the size and number of the integrated microstructures. Aside of fluid driven metallic microstructure devices like the famous Karlsruhe Cube, electrically powered devices have been developed and applied for temperature ranges where thermoliquids reach their limits or the use of gases may be disadvantageous due to their high viscosity and the arising pressure drop. In this publication several microstructure devices for heating and evaporation of fluids as well as for chemical reactions are presented in overview style. Details on manufacturing and device properties are given. Some process examples and experimental data for different types of microstructure devices are shown. Fouling problems are discussed briefly by an example.