Studies of liquid--gaseous two-phase systems by positron emitting radiotracers

Positron emission tomography (PET) is an established tool for clinical diagnosis and research. An increasing number of non-medial applications are known. Based on this technique, feasibility tests were carried out on radiotracer applications in liquid-gaseous two-phase systems. A density measurement technique was successfully tested utilizing the density dependence of the positron range. In this case, a locally fixed 45Ti source was used. The spreading of a liquid tracer distribution in a bubbly flow was monitored, and the dispersion coefficient for the tracer in the liquid phase was determined. Here, 18F was used as the tracer.