3D-PTV measurement verified by UVP for unsteady and three-dimensional flow inside a suction sump

Abstract

Our aim is to understand the complicated flow inside a suction sump in the vertical-wet-pit-pump configuration. The information of unsteady and three-dimensional flow structures is useful, not only for this complicated flow but also for other complicated flows which are commonly seen in various practical applications. To acquire such information, a three-dimensional particle tracking velocimetry (3D-PTV) technique is one solution. However, this technique includes more unknown factors in reliability and accuracy than other well-established measuring techniques. In the present study, we examine the simultaneous measurement using both of the 3D-PTV and another velocimetry, namely, an ultrasonic velocity profiler (UVP) with common tracer particles. This simultaneous measurement is expected to become an effective method to dissolve the above fatal defect of the 3D-PTV. As a result, we have successfully found out the suitable condition for the simultaneous measurement with high accuracy. Then, under this condition, we have revealed the time-mean and instantaneous velocity vectors of the unsteady and three-dimensional flow inside the suction sump.

Keywords

• suction sump
• open sump
• three-dimensional flow
• unsteady flow
• ptv
• uvp
• pump
• two-phase flow