The Development of a Multi-dimensional Image Processing System for Complex Flow Field Diagnostics

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Extensive investigations about multi-dimensional image processing technique development for complex flow field diagnostics with high accuracy had been conducted in the pres8nt study. Advanced techniques for the simultaneous measurement of the vector (velocity) fields and scalar (spices concentration and/or temperature) fields in fluid flows had also been developed. Taking the advantage of these advanced techniques, a multi-dimensional image processing system for complex flow field diagnostics with high accuracy had been constructed- The specialized software for the multi-dimensional image processing system to do complicated multi-dimensional information extraction with high accuracy from the acquiring images had been developed. By using the artificial visualization images, various Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV) image processing algorithms had been evaluated, and optimized methods for turbulence flow measurement accuracy improved had also been 1 … More 3uggested. The hardware of the multi-dimensional image processing system includes high-power double-pulsed Nd : YAG Lasers, high resolution cross-correlation CCD cameras, excellent-performanced host computer arid colossal memory for the whole-field, time-dependent and high spatial-resolved digital image acquiring and processing. Both PIV and Laser Induced Fluorescence (LIF) techniques were used to conduct simultaneous vector (velocity) and scalar (temperature and/or spices concentration) fields measurement of fluid flows.By using the multi-dimensional image processing system, a self-induced sloshing phenomena in a rectangular tank was investigated. The whole system performance and accuracy level of the multi-dimensional image processing system was evaluated through the comparison of the measurement results of the present system with the LDV (Laser Doppler Velocimenty) measurement data, which Were considered to have very high accuracy level. Based oh the measurement results of the present system to a lobed jet mixing flow and a circular jet flow, the evolution processes of various turbulent and vertical structures in the jet mixing flows were visualized quantitatively. The mechanism of the mixing enhancement of lobed nozzles over conventional circular nozzles was also analyzed. Which also demonstrated the versatile feasibility of the present system for complex flow diagnostics.In cooperation with computational Fluid Dynamics (CFD) methods, the present system may also be further developed into a hybrid system for complex flow diagnostics, which is considered to be the fashion of future fluid dynamics diagnostic system. Less