Experimental Set-up
|
|
|
|
|
|
For the nozzle geometry, experimental measurements of the micro-scale flow fields will be performed using Molecular Fluorescence Velocimetry (MFV) and Micro-Particle Image Velocimetry. The experimental study will use two different full-field velocity mapping techniques : 1) a molecular fluorescence tagging velocimetry technique using caged dye molecules (~7nm in size) for flow tagging, and 2) a Micro-PIV technique using fluorescent hollow glass spheres (20~100nm diameter) for tagging. These two techniques will be used to supplement each other depending on the field-of-view size. The former technique measures temporal and spatial development of Lagrangian velocity profiles and the use of ultra-small seeding molecules will allow measurement for the microscale regions, such as the flow just before and after the nozzle exit. The latter measures Eulerian velocity vector field with relatively larger meso-scale spatial range of the flow (still on the order of 100 micro-meter), such as the flow near the reservoir or upstream of the nozzle.