In modern times, expert experimentalists have to rely on complex and expensive laser velocimeters to calculate the liquid flow at the wall. Such techniques include molecular tagging velocimetry, particle tracking velocimetry, particle image velocimetry, etc. It would be beneficial for many practical and industrial applications to have a system that can be mounted on a surface boundary and measure local streamlines, near-wall velocity, and wall shear stress. GW researchers have developed a wall-mounted device to measure near-wall velocimetry. It is an optical-based approach where all the optics and imagers can be integrated into a very compact package. The measurement is made through fiber bundles coupled to detectors (either photodiode, photomultiplier tubes, camera sensors, etc). Several combinations of tracers and fiber bundles are possible and this allows us to reach different near-wall quantities. The system is compact and calibration-free, and the fiber enables deployment in harsh environments.
Figure 1. Single line or ring of fiber downstream of the injection port Advantages:
Applications: