Abstract: The 3D printing is a combination of digital technology, material science, intelligent manufacturing and control of opto-mechatronics systems. It is called the third industrial revolution from the view of the Economist Journal. A color 3D printing machine may provide the necessary support for high value-added industrial and commercial design, architectural design, personal boutique, and 3D artist’s creation. The main goal of this paper is to develop photo-curable color 3D manufacturing technology and system implementation. The key technologies include (1) Photo-curable color 3D additive manufacturing processes development and materials research (2) Piezo type ink-jet head control and Opto-mechatronics integration technique of the photo-curable color 3D laminated manufacturing system. The proposed system is integrated with single Piezo type ink-jet head with two individual channels for two primary UV light curable color resins which can provide for future colorful 3D printing solutions. The main research results are 16 grey levels and grey resolution of 75 dpi.
Abstract: Power Regeneration in Refrigeration Plant concept
has been analyzed and has been shown to be capable of saving about
25% power in Cryogenic Plants with the Power Regeneration System
(PRS) running under nominal conditions. The innovative component
Compressor Expander Group (CEG) based on turbomachinery has
been designed and built modifying CETT compressor and expander,
both selected for optimum plant performance. Experiments have
shown the good response of the turbomachines to run with R404a as
working fluid. Power saving up to 12% under PRS derated conditions
(50% loading) has been demonstrated. Such experiments allowed
predicting a power saving up to 25% under CEG full load.
Abstract: The turbulent structures in the wake (x/d =10 to 60) of a screen cylinder have been educed to understand the roles of the various structures as evolving downstream by comparing with those obtained in a solid circular cylinder wake at Reynolds number, Re of 7000. Using a wavelet multiresolution technique, the flow structures are decomposed into a number of wavelet components based on their central frequencies. It is observed that in the solid cylinder wake, large-scale structures (of frequencyf0 and 1.2 f0) make the largest contribution to the Reynolds stresses although they start to lose their roles significantly at x/d> 20. In the screen cylinder wake, the intermediate-scale structures (2f0 and 4f0) contribute the most to the Reynolds stresses atx/d =10 before being taken over by the large-scale structures (f0) further downstream.
Abstract: Thewake flow behind two yawed side-by-sidecircular
cylinders is investigated using athree-dimensional vorticity probe.
Four yaw angles (α), namely, 0°, 15°, 30° and 45° and twocylinder
spacing ratios T*
of 1.7 and 3.0 were tested. For T*
= 3.0, there exist
two vortex streets and the cylinders behave as independent and
isolated ones. The maximum contour value of the coherent streamwise
vorticity ~* ωx
is only about 10% of that of the spanwise vorticity ~* ωz
.
With the increase of α,
~* ωx
increases whereas ~* ωz
decreases. At α =
45°, ~* ωx
is about 67% of ~* ωz
.For T* = 1.7, only a single peak is
detected in the energy spectrum. The spanwise vorticity contours have
an organized pattern only at α = 0°. The maximum coherent vorticity
contours of ~* ω x
and ~* ωz
for T*
= 1.7 are about 30% and 7% of those
for T*
= 3.0.The independence principle (IP)in terms of Strouhal
numbers is applicable in both wakes when α< 40°.
Abstract: Ultrafast doped zinc oxide crystal promised us a good
opportunity to build new instruments for ICF fusion neutron
measurement. Two pulsed neutron detectors based on ZnO crystal
wafer have been conceptually designed, the superfast ZnO timing
detector and the scintillation recoil proton neutron detection system.
The structure of these detectors was presented, and some characters
were studied as well. The new detectors could be much faster than
existing systems, and would be more competent for ICF neutron
diagnostics.
Abstract: The hydrodynamic and thermal lattice Boltzmann
methods are applied to investigate the turbulent convective heat
transfer in the wavy channel flows. In this study, the turbulent
phenomena are modeling by large-eddy simulations with the
Smagorinsky model. As a benchmark, the laminar and turbulent
backward-facing step flows are simulated first. The results give good
agreement with other numerical and experimental data. For wavy
channel flows, the distribution of Nusselt number and the skin-friction
coefficients are calculated to evaluate the heat transfer effect and the
drag force. It indicates that the vortices at the trough would affect the
magnitude of drag and weaken the heat convection effects on the wavy
surface. In turbulent cases, if the amplitude of the wavy boundary is
large enough, the secondary vortices would be generated at troughs
and contribute to the heat convection. Finally, the effects of different
Re on the turbulent transport phenomena are discussed.
Abstract: Intravitreal injection (IVI) is the most common treatment for eye posterior segment diseases such as endopthalmitis, retinitis, age-related macular degeneration, diabetic retinopathy, uveitis, and retinal detachment. Most of the drugs used to treat vitreoretinal diseases, have a narrow concentration range in which they are effective, and may be toxic at higher concentrations. Therefore, it is critical to know the drug distribution within the eye following intravitreal injection. Having knowledge of drug distribution, ophthalmologists can decide on drug injection frequency while minimizing damage to tissues. The goal of this study was to develop a computer model to predict intraocular concentrations and pharmacokinetics of intravitreally injected drugs. A finite volume model was created to predict distribution of two drugs with different physiochemical properties in the rabbit eye. The model parameters were obtained from literature review. To validate this numeric model, the in vivo data of spatial concentration profile from the lens to the retina were compared with the numeric data. The difference was less than 5% between the numerical and experimental data. This validation provides strong support for the numerical methodology and associated assumptions of the current study.