Particle Measurement

Dr.-Ing. Franz Huber

The main aim of the group Particle Measurement is to understand and eventually control the formation of nanoparticles. To that end we develop laser optical measurement techniques for the characterization of particles in the gas and liquid phase.

In many practical combustion processes nanoscale soot is formed as a side product due to incomplete combustion, which became a matter of public interest especially in the case of emissions from combustion engines. On the other hand carbon blacks and nanoparticles from many other materials like metals, metalloids and their oxides are produced in large quantities as highly specialized industrial products.

These nanoparticles are used in a wide field of applications. As an example carbon blacks are employed as black pigments (paints, toners) and bulking agents (e.g. in rubber industry). Due to their very large active surface they are also widely used as catalysts. Furthermore, particles are used in sunblockers (as UV protection), gas sensors, conductive plastics, scratch-proof surfaces or as transparent transistors for displays and solar panels.

As the functional properties of the particles and thus later product properties strongly depend on size and morphological parameters measurement techniques for a comprehensive characterization are required. The techniques developed at LTT allow for an in-situ determination of particle concentrations and morphological parameters. As for a comprehensive understanding of particle formation processes temperature and flow fields are of major interest we develop optical techniques for a comprising determination of formation conditions. 

Optical techniques such as scattering methods can also be used to investigate particle formation is the liquid phase. In a current research topic we explore the formation and growth of gas hydrates.

Scheme of fractal aggregate
Laser-optical investigation of soot formation
Soot particle from a premixed flame
Tin dioxide particle from a gas-phase synthesis process