Simultaneous Particle Imaging Velocimetry and Thermometry (PIVT) in Reacting Flows by Using Lanthanide Doped Nanoparticles

The goal for the proposed Phase I research is to develop a new particle imaging velocimetry and thermometry (PIVT) method to measure velocity and temperature distributions simultaneously in reactive and non-reactive flows by using lanthanide doped nanoparticles. Specifically, the proposed study includes four research tasks. First, lanthanide doped upconversion and down-conversion of oxide and fluoride nanoparticles will be synthesized and their photo-physical properties will be characterized. Second, the dependence of temperature sensitivity of oxide and silica coated fluoride nanoparticles on lanthanide ion concentrations, particle size, and host materials will be measured. Third, simultaneous measurements of temperature and velocity in a non-reactive counterflow will be conducted by using lanthanide doped nanoparticles. Finally, the feasibility of the phosphor based PIVT method for the measurements of temperature and velocity in a counterflow diffusion flame will be demonstrated and the effect of thermal radiation from the particles on the experimental accuracy will be investigated. The advantages of the present method include but not limited to low cost, high temperature sensitivity, non-intrusive measurements capability, low background scattering effect, and low pressure dependence. The success of the proposed research will enable simultaneous measurements of velocity and temperature in propulsion systems and contribute to the understanding of the physical processes and optimization of engine design.