Abstract Studies of phase speciation of trace metals were conducted in Kaohsiung harbor and coastal areas in April and May 2002. Water samples were collected from three different sampling stations to study the spatial distribution of metal species. Colloidal and truly dissolved subsamples were observed by cross-flow filtration treatment. The results show that TOC of seawater samples ranged from 4.17 mg/L to 7.17 mg/L. For trace metals, zinc had the highest concentration(7.21 £gg/L ¡ã14.14 £gg/L), followed by manganese(3.31 £gg/L ¡ã 11.73 £gg/L), copper(0.28 £gg/L ¡ã 7.57 £gg/L), lead(2.41 £gg/L ¡ã 4.41 £gg/L), nickel(1.78 £gg/L ¡ã 2.97 £gg/L). Highest concentrations of TOC and metals were observed in Kaohsiung harbor(S1), and the values decreased in the order of S1 ¡Ö S2 ¡Ö S3. Distribution of phase speciation of trace metals varied with location. Nickel existed in truly dissolved phase predominately(66 ¢Mat S1, 79.7 ¢Mat S2 and 84.6 ¢Mat S3). For the other metals, either particle or truly dissolved phase was the major species at each sampling station. For zinc, 56.1 ¢Mat S1 was in truly dissolved phase, 68.1 ¢Mat S2 and 59.6 ¢M at S3 were in particulate phase. For copper, 67.5 ¢Mat S1 was in particulate phase, 56.7 ¢Mat S2 and 89.9 ¢Mat S3 were in truly dissolved phase. For manganese, 56.3 ¢Mat S1 was in truly dissolved phase, 79.8 ¢Mat S2 and 72.1 ¢Mat S3 were in particulate phase. For lead, 51.7 ¢Mat S1 and 66.0 ¢Mat S3 were in truly dissolved phase, 63.5 ¢Mat S2 was in particulate phase. The percentages of TOC and metals in colloidal phase of the filter-passing pool were low at all sampling stations and decreased in the order of S1 ¡Ö S2 ¡Ö S3. They were found predominately in truly dissolved fraction. The results also show that Kaohsiung harbor (S1) had the highest percentage of colloidal fraction, followed by coastal water (S2), open sea (S3). Values of partition coefficient between colloids and true solution(Kc ) in the Kaohsiung harbor and nearby coastal areas were lower than the Kc values observed in Galveston Bay during July 1995.

Approved for public release, distribution unlimited / Over the past few decades, advances in aeronautic and control technologies have established a new vision for future air transportation systems. NASA has initiated the motion with several programs supporting the "highway of the sky," a system of launch pads and air pathways enabling smaller and more easily piloted aircraft to travel the open space above instead of busy freeways and crowded city streets. Previous investigations into crossflow fan technology as a propulsion source have identified its potential for use in personal aircraft and vertical takeoff and landing applications. To further development, performance characteristics must be determined for the possible configurations and under variable conditions to understand factors critical to design. This experiment studied flow characteristics of a crossflow fan incorporating 30 blades of six inch length in a six inch diameter rotor. Comparison was made against the performance of a fan of similar design but one-fourth the length span previously tested. Results were plotted for various parameters along constant speed lines of operation and general trends were determined. These results were used to quantitatively deduce scaling relationships for this device. / US Navy (USN) author.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2009. / Thesis Advisor(s): Hobson, Garth V. ; Gannon, Anthony. "September 2009." Author(s) subject terms: Fan, cross-flow, crossflow, inlet guide vanes, thrust vectoring, vertical take off. Description based on title screen as viewed on Nov. 5, 2009. Includes bibliographical references (p. 95). Also available in print.

The tap-water treated by water treatment plants in southern Taiwan is coming from surface water of the rivers, subsurface stream and underground water of deep wells. The original raw water possesses were high level of hardness and ammonia- nitrogen solute due to affection by terrain, geology and human activities within water origin area. And considering the water quality from Kao-ping river origin is hard to control during in rain fall and dry season, we were to construction efficiency procedure of water treatment to obtain a high quality of drink water. There were high hardness and TDS from strata limestone of groundwater to increase treatment difficulty in southern Taiwan water treatment plant. Therefore, recommended that the influent water standards were limited hardness and silicate (SiO2) less than 300 mg/L and 15 mg/L, respectively. On the other hand, the metal substances Ca, Mg, Si and Al in influent water were 74.3 mg/L, 18.7 mg/L, 12.9 mg/L and 0.1 mg/L, respectively. Results show high inorganic substances that could increase the treatment loading. This project of the study, were make sure the problem of membrane clogging and fouling happened to the finest water treatment plants who use LPRO membrane system to remove the impurity in the influent water. Moreover, by accumulation of processes operation experience on site were according to water quality statistics data and membrane autopsy of single LPRO membrane by processes. In the same time, we prepared three single tube of RO membrane to experiment on site and collected data from before and after antifouling additive, that could find the membrane fouling and clogging results of the influent raw water. Obviously, the influent raw water quality into LPRO membrane is closely connected to the efficiency of treatment plant. The results show when the temperature decreased of influent raw water that could decrease the effluent volume from LPRO, because the water temperature affected by increase viscosity of raw water. The first part clogging substances of membrane were aluminum (Al), that could be use aluminate coagulant to make increase more aluminum. And the TOC value of the effluent were from 0.2 to 1.4 mg/L, that shows the effluent water was kept stably but UV254 value were have more than 75% efficiency. Results of organic analysis on LPRO effluent indicates the pretreatment process could leave annular structure organic. In other hand, when using EEFM to analysis the spectra sampling of organic of LPRO, there finding a lot low emission wavelength fluoresces of influent on EX/EM 230/340 and decrease the wavelength fluoresces value on EX/EM 280/330 and 240/340 by RO membrane system of LPRO. To be worth mentioning, when organism of sampling fluoresces value during high emission wavelength on EX/EM 240/400 nm was disappeared, that indicates RO membrane has good performance to separation organism of water. And results of elements analysis on RO membrane surface were using SEM and EDX have a lot aluminum and silicate on segment RO membrane module. Therefore, results show pretreatment process of coagulation and sedimentation could not treatment metal substances and organic efficiency, that was to effect directly cause to make the problems of membrane fouling and clogging.

Abstract The experiment was performed to measure the flow-induced vibration of tubes in cross flow and to study the effect of different experimental parameters, natural frequency, tube patterns and positions of the missing tube, on the tube vibration. The vibration mode of structures was investigated by root-mean-square values of tube displacements, dominant response frequencies, power spectral densities and orbits. The vibration signals in various velocities were used to analyze the mode and mechanism of the tube vibration by examining the interrelations between power spectral densities and orbits of the tube vibration. It was found that the stability thresholds were higher at the higher natural frequencies of the tubes and approach angles of the flow. Missing tube would affect the stability of local flow field, so that the surrounding tubes became more unstable. For each array pattern, the dominant response frequency of tube was changed with the flow velocity. It should be associated with the flow field, the mode and mechanism of vibration. As the tube frequency jumped, it should be the change of vibrating mode and mechanism. From the spectra and orbits of the tube vibrations, it can be found that the dominant frequencies are more complex at the high flow velocity.

Flow induced vibration of flow around a flexible tube array in cross flow are investigated experimentally. The different parameter including velocity, turbulent intensity, and nature frequency of tube. The flow structure and stability between flow and tube are analyzed by flow visualization and flow measurement. Further more, missing tube to find the change of the flow and the influenced of nearby tube, to get the way decreasing the vibration of tube.

ABSTRACT The flow-induced vibrations of tubes in a rotated triangular array subject to cross flow are investigated numerically and experimentally. The parameters are inlet velocity of cross flow, number of tube, and tube natural frequency. In the study, the instantaneous fluid forces on tube surfaces are computed numerically, the instantaneous displacement of the tubes due to the fluid forces is calculated, and thus the motions of the tubes in cross flow are described. Experiments are also conducted to compare the numerical results. The tube vibrations in a water tunnel are measured by two accelerometers. The amplitudes, spectra, and trace of tube motion are presented. The critical velocities of tube vibrations are then determined. Experimental results show that some tubes vibrate seriously when the flow velocity increases up to a critical value, and hysteresis of the tube vibrations is observed. In case of the seven-tube array, the tubes in the fourth row exhibit the most serious vibration. When the flow velocity is above the critical value, only one dominant frequency of the tube vibrations is detected, comparing to multiple dominant frequencies in subcritical condition. Furthermore, the tube in supercritical condition behaves like a limit cycle, especially when the natural frequency is equal to or near the vortex shedding frequency from the upstream tubes. It is also shown that the critical velocity decreases with more surrounding tubes in the upstream and does not change as more adjacent tubes are added in the downstream. However, the tube number seems to have no effect on the critical velocity when the tube natural frequency is far from the vortex shedding frequency.

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No description available.

This research is a follow up to preliminary studies reported by Beier and Sego (2008) and the objective is to investigate laboratory scale dewatering of oil sands total tailings using cross flow filtration technology. A laboratory experiment was setup in Oil Sands Tailings Research Facility and tests were carried out under different operational conditions using different tailings. The experiments showed clean filtrate water generated under all test conditions. Coarser tailings and higher filter pipe porosity resulted in greater filtrate flux rate. The effect of slurry velocity, residual bitumen, and transmembrane pressure on cross flow filtration performance was also evaluated. A dimensional analysis was developed using the laboratory tests to establish the relationships between measured parameters and to assist and guide future experimental programs. / Geotechnical Engineering