TOMOGRAPHIC MEASUREMENT TECHNIQUES - VISUALIZATION OF MULTIPHASE FLOWS

Tomographic measurement techniques have become increasingly popular fo r the application in the field of chemical and process engineering. Wi th this techniques, the fields of density, concentration, temperature, velocity or local void fraction can be measured without interfering w ith the multiphase now. These fields are often either instationary or even have transient character. Therefore, the used tomographic measure ment techniques have to have a high spatial and temporal resolution. I n this paper known tomographic measurement systems are described and c ompared to each other. The sensor systems and reconstruction methods a re explained. As an example, the applications of electrical and x-ray tomography are described for the imaging the flow inside random and st ructured packings. With the electrical tomographic measurement techniq ue a temporal resolution of up to 100 frames per second is achieved, w hereas with the x-ray tomography spatial resolutions of 0.4mm are poss ible.