A direct measure of the frequency response of hot-wire anemometers: temporal resolution issues in wall-bounded turbulence

Abstract

Based on the need to characterise the accuracy of hot-wire anemometry (HWA) in high Reynolds number wall-bounded turbulence, we here propose a novel direct method for testing the frequency response of various systems to very high frequency velocity fluctuations (up to 50 kHz). A fully developed turbulent pipe flow is exploited to provide the input velocity perturbations. Utilising the unique capabilities of the Princeton Superpipe, it is possible to explore a variety of turbulent pipe flows at matched Reynolds numbers, but with turbulent energy in different frequency ranges. Assuming Reynolds number similarity, any differences between the appropriately scaled energy spectra for these flows s..