Three dimensional nanoscale fabrication and modeling of dynamic mode multidirectional UV lithography

Abstract The large-scale circulation (LSC) is the most fundamental turbulent coherent flow structure in Rayleigh-B\'enard convection. Further, LSCs provide the foundation upon which superstructures, the largest observable features in convective systems, are formed. In confined cylindrical geometries with diameter-to-height aspect ratios of Γ ≅ 1, LSC dynamics are known to be governed by a quasi-two-dimensional, coupled horizontal sloshing and torsional (ST) oscillatory mode. In contrast, in Γ ≥ √2 cylinders, a three-dimensional jump rope vortex (JRV) motion dominates the LSC dynamics. Here, we use dynamic mode decomposition (DMD) on direct numerical simulation data of liquid metal to show that both types of modes co-exist in Γ = 1 and Γ = 2 cylinders but with opposite dynamical importance. Furthermore, with this analysis, we demonstrate that ST oscillations originate from a tilted elliptical mean flow superposed with a symmetric higher order mode, which is connected to the four rolls in the plane perpendicular to the LSC in Γ = 1 tanks.

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Three-dimensional organic microlasers with low lasing thresholds fabricated by multiphoton and UV lithography

Optics Express ◽

10.1364/oe.22.012316 ◽

2014 ◽

Vol 22 (10) ◽

pp. 12316 ◽

Cited By ~ 14

Author(s):

Vincent W. Chen ◽

Nina Sobeshchuk ◽

Clément Lafargue ◽

Eric S. Mansfield ◽

Jeannie Yom ◽

...

Keyword(s):

Three Dimensional ◽

Uv Lithography

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Simultaneous Measurement of Free Surface Elevation and Three-Component Velocity Field Around a Translating Surface-Piercing Foil

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4038586 ◽

2018 ◽

Vol 140 (3) ◽

Author(s):

James Schock ◽

Jason Dahl

Keyword(s):

Particle Image Velocimetry ◽

Free Surface ◽

Velocity Field ◽

Numerical Methods ◽

Flow Field ◽

Particle Image ◽

Laser Sheet ◽

Three Dimensional ◽

Dynamic Mode ◽

Image Velocimetry

Two methods are investigated to simultaneously obtain both three-dimensional (3D) velocity field and free surface elevations (FSEs) measurements near a surface piercing foil, while limiting the equipment. The combined velocity field and FSE measurements are obtained specifically for the validation of numerical methods requiring simultaneous field data and free surface measurements for a slender body shape. Both methods use stereo particle image velocimetry (SPIV) to measure three component velocities in the flow field and both methods use an off the shelf digital camera with a laser intersection line to measure FSEs. The first method is performed using a vertical laser sheet oriented parallel to the foil chord line. Through repetition of experiments with repositioning of the laser, a statistical representation of the three-dimensional flow field and surface elevations is obtained. The second method orients the vertical laser sheet such that the foil chord line is orthogonal to the laser sheet. A single experiment is performed with this method to measure the three-dimensional three component (3D3C) flow field and free surface, assuming steady flow conditions, such that the time dimension is used to expand the flow field in 3D space. The two methods are compared using dynamic mode decomposition and found to be comparable in the primary mode. Utilizing these methods produces results that are acceptable for use in numerical methods verification, at a fraction of the capital and computing cost associated with two plane or tomographic particle image velocimetry (PIV).

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Moving mask UV lithography for three-dimensional structuring

Journal of Micromechanics and Microengineering ◽

10.1088/0960-1317/17/2/003 ◽

2006 ◽

Vol 17 (2) ◽

pp. 199-206 ◽

Cited By ~ 62

Author(s):

Yoshikazu Hirai ◽

Yoshiteru Inamoto ◽

Koji Sugano ◽

Toshiyuki Tsuchiya ◽

Osamu Tabata

Keyword(s):

Three Dimensional ◽

Uv Lithography

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A numerical study of shear layer characteristics of low-speed transverse jets

Journal of Fluid Mechanics ◽

10.1017/jfm.2016.7 ◽

2016 ◽

Vol 790 ◽

pp. 275-307 ◽

Cited By ~ 13

Author(s):

Prahladh S. Iyer ◽

Krishnan Mahesh

Keyword(s):

Velocity Profile ◽

Shear Layer ◽

Convective Instability ◽

Numerical Study ◽

Velocity Ratio ◽

Mixing Layer ◽

Three Dimensional ◽

Dynamic Mode Decomposition ◽

Dynamic Mode ◽

Dominant Frequencies

Direct numerical simulation (DNS) and dynamic mode decomposition (DMD) are used to study the shear layer characteristics of a jet in a crossflow. Experimental observations by Megerian et al. (J. Fluid Mech., vol. 593, 2007, pp. 93–129) at velocity ratios ($R=\overline{v}_{j}/u_{\infty }$) of 2 and 4 and Reynolds number ($Re=\overline{v}_{j}D/{\it\nu}$) of 2000 on the transition from absolute to convective instability of the upstream shear layer are reproduced. Point velocity spectra at different points along the shear layer show excellent agreement with experiments. The same frequency ($St=0.65$) is dominant along the length of the shear layer for $R=2$, whereas the dominant frequencies change along the shear layer for $R=4$. DMD of the full three-dimensional flow field is able to reproduce the dominant frequencies observed from DNS and shows that the shear layer modes are dominant for both the conditions simulated. The spatial modes obtained from DMD are used to study the nature of the shear layer instability. It is found that a counter-current mixing layer is obtained in the upstream shear layer. The corresponding mixing velocity ratio is obtained, and seen to delineate the two regimes of absolute or convective instability. The effect of the nozzle is evaluated by performing simulations without the nozzle while requiring the jet to have the same inlet velocity profile as that obtained at the nozzle exit in the simulations including the nozzle. The shear layer spectra show good agreement with the simulations including the nozzle. The effect of shear layer thickness is studied at a velocity ratio of 2 based on peak and mean jet velocity. The dominant frequencies and spatial shear layer modes from DNS/DMD are significantly altered by the jet exit velocity profile.

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Civil Engineering Construction Management Based on BIM Technology

Forest Chemicals Review ◽

10.17762/jfcr.vi.47 ◽

2021 ◽

Author(s):

Jin Qiaolan, Zhang Bin

Keyword(s):

Construction Management ◽

Civil Engineering ◽

Three Dimensional ◽

Dynamic Mode ◽

Construction Engineering ◽

Engineering Construction ◽

Construction Market ◽

Whole Process ◽

Efficient Construction

The application of BIM Technology in civil engineering construction is one of the important trends of the innovation and development of the current construction market and the realization of efficient construction. Through the application of BIM Technology in civil engineering, the whole process of engineering construction can be monitored and managed, the whole civil engineering construction level can be improved, and the quality of engineering construction can be met. In this paper, through the application of BIM Technology in the construction management of construction engineering, the information technology means, visual characteristics and dynamic mode strengthening project management model based on itself are studied. In this paper, through the three-dimensional technical means to build the model, strengthen the systematic supervision of the construction project. The experimental results show that the model can better guarantee the construction completion on schedule, improve the construction quality and reduce the construction cost.

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Introduction of DMD Method to Study the Dynamic Structures of a Three-Dimensional Centrifugal Compressor with and without Flow Control

Energies ◽

10.3390/en11113098 ◽

2018 ◽

Vol 11 (11) ◽

pp. 3098 ◽

Cited By ~ 4

Author(s):

Shuli Hong ◽

Guoping Huang ◽

Yuxuan Yang ◽

Zepeng Liu

Keyword(s):

Flow Field ◽

Flow Control ◽

Centrifugal Compressor ◽

Coherent Structures ◽

Three Dimensional ◽

Great Influence ◽

Flow Structures ◽

Small Scale ◽

Dynamic Mode ◽

Blade Tip

The flow structures around the blade tip, mainly large-scale leakage vortex, exert a great influence on compressor performance. By applying unsteady jet control technology at the blade tip in this study, the performance of the compressor can be greatly improved. A numerical simulation is conducted to study the flow characteristics of a centrifugal compressor with and without a flow control. The complex flow structures cause great difficulties in the analysis of the dynamic behavior and flow control mechanism. Thus, we introduced a dynamic flow field analysis technology called dynamic mode decomposition (DMD). The global spectrums with different global energy norms and the coherent structures with different scales can be obtained through the DMD analysis of the three-dimensional controlled and uncontrolled compressors. The results show that the coherent structures are homogeneous in the controlled compressor. The leakage vortex is weakened, and its influence range of unsteady fluctuation is reduced in the controlled compressor. The effective flow control created uniform vortex structures and improved the overall order of the flow field in the compressor. This research provides a feasible direction for future flow control applications, such as transferring the energy of the dominant vortices to small-scale vortices.

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