Acquisition of Advanced Instrumentation for Research in Turbulence, Chaos, Combustion and two-Phase Flows

点击翻译按钮获取中文摘要

ABSTRACT CTS-9413798 Fazle Hussain A coherent, multi-purpose measurement system to address the future challenges in a number of major areas of hydrodynamics will be developed. The instrumentation will help studies about the structure, dynamics and control of turbulence phenomena, including two-phase and free surface flows, utilizing: (i) particle image velocimetry (PIV), (ii) multipoint vorticity and pressure measurements, and (iii) data processing. The first system component consists of lasers, cameras, frame digitizes, particle size and high-speed computational equipment necessary to implement cine holographic particle velocimetry (cine HPV) and digital PIV. The second component system contains a 128-channel data acquisition system (with 16-bit resolution, low noise and sample rates up to 100 kHz/channel) and real-time signal analyzers. The third system component consists primarily of a graphics workstation for analysis of 3D velocity and vorticity fields obtained via (i) and (ii) and also numerical simulation. The Aerodynamics and Turbulence Laboratory (ATL) at the University of Houston has both fundamental and applied studies in hydrodynamics and related topics (e. g. dynamics of coherent structures (CS), turbulence management, chaos in open flows, and vortex reconnection and core dynamics, hemispherical microphone arrays, CS education). Combination of experimental and numerical techniques have been used to address various topics: (i) the nature and dynamical significance of CS in free shear flows, including their role transition, entrainment mixing and combustion, and (iii) the role of vortex reconnection in turbulence cascade. A major thrust here is implementing cine HPV, which can provide time-resolved, 3D velocity, vorticity and temperature field data. A time-resolved flow field measurements techniques using HPV is the most promising future flow measurement technology. The new instrument will implement cine HPV, capturing evolving flow fields at rates up to 1 kHz. In addition, the velocity and pressure measurements will be applied to study CS dynamics in technological floes and develop innovative numerical simulation techniques (wavelet-based large-eddy simulations) and to analyze in detail turbulence phenomena. The use of these instruments will not only advance our understanding of flow physics but also train graduate students and researchers in state-of-the-art measurement techniques, thus paving the way for further innovations. These instruments will be used primarily by researchers at ATL but will also be available to researchers in engineering, mathematics and physics. ***