Mechanical Engineering - Research Publications
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ItemThe effects of laser-sheet misalignment on Stereo-PIV measurements in wall-bounded turbulence(Australasian Fluid Mechanics Society, 2016)
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ItemCharacteristics of the entrainment velocity in a developing wake(International Symposium on Turbulence and Shear Flow Phenomena, 2015)
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ItemNo Preview AvailableNumerical investigation of the behaviour of wall shear stress in three-dimensional pulsatile stenotic flows(Australasian Fluid Mechanics Society (AFMS), 2014)
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ItemSurface shear stress fluctuations in the atmospheric surface layer( 2006)A lightweight, high frequency response, floating element sensor was used to measure wall shear stress fluctuations in an atmospheric surface layer. The sensor uses a laser position measurement system to track the motion of the floating element. The measurements were taken as part of an internationally coordinated experimental program designed to make extensive spatial and temporal measurements of velocity, temperature and wall shear stress of the surface layer. Velocity measurements were made with both a 27m high vertical array and a 100m wide horizontal array of sonic anemometers; 18 anemometers in total were employed. Cross-correlations of shear stress and streamwise velocity fluctuations were analysed in an attempt to identify structure angles in the flow. The results were shown to compare favourably with experimental data from controlled, laboratory turbulent boundary layer measurements at three orders of magnitude lower Reynolds number.
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ItemTurbulence intensity similarity formulations for wall-bounded flows(CIMNE - International Center for Numical Methods in Engineering, 2004)
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ItemObservations on high Reynolds number turbulent boundary layer measurements(The University of Sydney, 2004)
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ItemSpanwise periodicity and the existence of very large scale coherence in turbulent boundary layers(Begellhouse, 2005-12-01)
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ItemDominant spanwise Fourier modes, and the existence of very large scale coherence in turbulent boundary layers( 2004)Multiple plane stereo PIV results and data from a rake often hot-wire probes are used to investigate the largest scalestructures in a zero-pressure-gradient turbulent boundary layer.Instantaneous vector fields from stereo PIV in spanwise-streamwiseplanes reveal long low- and high-speed regions,with a length that often exceeds the viewing window (> 2d).Also evident is a remarkable degree of spanwise organisation,that manifests as a persistent spanwise stripiness in the u componentof the PIV vector field. Almost all trace of such spanwiseorganisation is lost in the mean statistics, presumably dueto the multitude of scales naturally present in wall-bounded turbulence.This can be overcome by ‘de-jittering’ the instantaneousvector fields. By sorting the data according to dominantspanwise fourier modes, and then applying simple statisticaltools to the sorted subsets, we are able to extract a clear viewof spanwise organisation. Results are confirmed in the variousPIV data-sets. Since the PIV fails to adequately capture the fullstreamwise extent of the low-speed regions, a rake of hot-wireprobes is also employed to capture a continuous view of thespanwise coherence. It is found that the low-speed regions arein fact extremely persistent in the streamwise direction, oftenexceeding 20 d in length. The fact that these long features meanderappreciably in the spanwise direction will limit the overallstreamwise length-scale as witnessed by a single probe or singlepoint statistic. For instance, premultiplied one-dimensionalspectra of the streamwise velocity (kxFuu) at this z/d show apeak contribution for characteristic lengthscales of 5-7d.
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ItemThree dimensional structure characterization and visualization in a turbulent boundary layer(CIMNE - International Center for Numical Methods in Engineering, 2004)