Practical Considerations for Simultaneous LDV {\&} PIV~Measurements~

Simultaneous LDV and PIV measurements are useful for validation experiments and~when correlating high temporal resolution measurements~with large~structures of the flow. ~~Performing simultaneous LDV and PIV measurements can be a challenging task due to the differences in temporal and spatial resolution of each technique, as well as requirements for adequate signal. Even so, simultaneous hot-wire and PIV measurements is even more difficult. ~Unlike~hot-wire, LDV~is a non-intrusive~technique that is unaffected by PIV laser light-sheet heating. Furthermore, hot-wire measurements are adversely affected by seeding particles in the flow required for PIV. ~In the present study, we discuss several practical considerations for performing simultaneous LDV and PIV measurements. ~We completed two separate experiments, each with~different seeding densities, flow velocities,~and working fluids. ~With these data sets, we~studied~the effects of temporal and spatial interpolation, up/down sampling, PIV window size and overlap on the simultaneous signals.~