Author(s): Francesco Albicini; Dadi Ram Dahal; Chirag Trivedi

Linked Author(s): Chirag Trivedi

Keywords: No Keywords

Abstract: This paper focuses on the performance analysis of a new water tunnel developed at NTNU’s Waterpower Laboratory, which would be used for experimental investigations of key fluid dynamic phenomena in hydropower. The rig is well suited for cavitation, fluid–structure interaction, submerged body vibrations and optical measurements such as particle image velocimetry (PIV). The test section (300×300×1175mm3) provides full optical access due to its transparent walls, while flow straighteners and flow conditioners ensure an even inflow. This paper presents the experimental characterisation of the facility across Reynolds numbers ranging from 4.9 × 105 up to 1.26 × 106. Average flow fields, velocity profiles and turbulence intensity were explored using PIV measurements, while vibrational behaviour was assessed using accelerometers mounted at key locations. Pressure and temperature monitoring were also implemented for a more comprehensive overview of the system. The results demonstrate an average turbulence intensity lower than 1.5% but also a slightly asymmetric flow in the upper level of the test section, with a maximum asymmetry value of less than 2%. A dominant vibration frequency, around 20Hz, affecting the rig’s dynamic response was detected as well.

DOI: https://doi.org/10.1088/1755-1315/1561/1/012006

Year: 2025