Construct and Validation of a Three-Dimensional Physical Model for Training in Transnasal Office Procedures

Aimed at the representative project which is protected by the downstream sediment storage dam, three dimensional flow velocity field in local scour area around the separate bridge pier via physical model test was studied. The influences of shaping the eroded pit caused by the velocities in different directions were analyzed. The distribution results of flow velocity field in local scour pit near the pier protected by the sediment storage dam, deduced from the paper, will provide references for the defensive design of bridge projects.

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NUMERICAL SIMULATION OF THREE DIMENSIONAL TSUNAMIS WATER WAVES GENERATED BY LANDSLIDES: COMPARISON BETWEEN PHYSICAL MODEL RESULTS, VOF AND SPH

Coastal Engineering 2006 ◽

10.1142/9789812709554_0129 ◽

2007 ◽

Author(s):

Paolo De Girolamo ◽

Tso-Ren Wu ◽

Philip L.-F. Liu ◽

Andrea Panizzo ◽

Giorgio Bellotti ◽

...

Keyword(s):

Numerical Simulation ◽

Physical Model ◽

Water Waves ◽

Three Dimensional

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A Three-Dimensional Physical Model of MRI Noise Based on Current Noise Sources in a Conductor

Journal of Magnetic Resonance ◽

10.1006/jmre.2000.2034 ◽

2000 ◽

Vol 147 (2) ◽

pp. 153-169 ◽

Cited By ~ 2

Author(s):

Michael J Hennessy

Keyword(s):

Physical Model ◽

Three Dimensional ◽

Current Noise ◽

Noise Sources

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Research on Mass Partition Coefficient for a Whole Car under Vertical and Lateral Road Excitations

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.29-32.177 ◽

2010 ◽

Vol 29-32 ◽

pp. 177-182 ◽

Cited By ~ 1

Author(s):

Long Wu

Keyword(s):

Partition Coefficient ◽

Physical Model ◽

Dimensional Space ◽

Three Dimensional ◽

Force Analysis ◽

Analytical Results ◽

Dynamical Coupling ◽

And Control ◽

Three Dimensional Space

Consider the imperfectness of mass partition coefficient for a whole car in automotive theories, a vehicle physical model with fourteen degree of freedoms under vertical and lateral road excitations is adopted as research background in this paper. With the help of force analysis of sprung mass in three dimensional space and investigations on vertical, lateral, pitch, roll and yaw motions, the ration relations of dynamical coupling between a whole suspension and four quarter suspensions are deduced and achieved. The analytical results obtained in this paper develop the theoretical content of mass partition coefficient. It will be utilized to analyze, test and control among different car suspensions in the fields of vibration, handling and steering systems in future.

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Mechanism design of a simplified 6-DOF 6-RUS parallel manipulator

Robotica ◽

10.1017/s0263574701003654 ◽

2002 ◽

Vol 20 (1) ◽

pp. 81-91 ◽

Cited By ~ 20

Author(s):

Xin-Jun Liu ◽

Jinsong Wang ◽

Feng Gao ◽

Li-Ping Wang

Keyword(s):

Mechanism Design ◽

Physical Model ◽

Parallel Manipulator ◽

Design Method ◽

Three Dimensional ◽

Solution Space ◽

Parallel Manipulators ◽

Dimensional Problem ◽

Spherical Joint ◽

Universal Joint

This paper concerns the issue of mechanism design of a simplified 6-DOF 6-RUS parallel manipulator. The design of robotic mechanisms, especially for 6-DOF parallel manipulators, is an important and challenging problem in the field of robotics. This paper presents a design method for robotic mechanisms, which is based on the physical model of the solution space. The physical model of the solution space, which can transfer a multi-dimensional problem to a two or three-dimensional one, is a useful tool to obtain all kinds of performance atlases. In this paper, the physical model of the solution space for spatial 6-RUS (R stands for revolute joint, U universal joint and S spherical joint) parallel manipulators is established. The atlases of performances, such as workspace and global conditioning index, are plotted in the physical model of the solution space. The atlases are useful for the mechanism design of the 6-RUS parallel manipulators. The technique used in this paper can be applied to the design of other robots.

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Simulation and Optimization of SCR System for Common-Rail Diesel Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.651-653.858 ◽

2014 ◽

Vol 651-653 ◽

pp. 858-861

Author(s):

Guan Qiang Ruan ◽

Jin Run Cheng

Keyword(s):

Diesel Engine ◽

Boundary Conditions ◽

Physical Model ◽

Three Dimensional ◽

Common Rail ◽

Experimental Results ◽

Bench Test ◽

Simulation And Optimization ◽

Scr System

The turbo diesel SCR system has been researched and analyzed in this paper. By using software of CATIA, three-dimensional physical model of SCR system has been established, and with software of AVL-FIRE, the boundary conditions have been set, simulated and optimized. In the process of SCR system optimizing, it mainly optimized the pray angle. Compare the effects of processing NOx to obtain batter optimization results. At last the optimization results are compared by bench test, and the experimental results are quite consistent with simulation.

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Numerical Analysis of a Compressor Type of Dehumidifier: (I) Fluid Flow

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132517500110 ◽

2017 ◽

Vol 25 (02) ◽

pp. 1750011 ◽

Cited By ~ 1

Author(s):

Xuan Quang Duong ◽

Jae Dong Chung

Keyword(s):

Physical Model ◽

High Performance ◽

Three Dimensional ◽

Computation Time ◽

Object A ◽

Porous Model ◽

Two Factors ◽

Fin Tube ◽

Dimensional Simulation ◽

Actual Shape

A three-dimensional simulation of a compressor dehumidifier was conducted by applying a porous model for condenser and evaporator, and a moving reference frame for the fan. A physical model was simulated for the unit cell of the actual shape of a fin-tube, and the parameters of viscous resistance and initial resistance were obtained. With these values, the porous model showed close agreement with the physical model within a reasonable computation time. A uniform flow across the evaporator and the condenser is desirable for high performance of the dehumidifier. Surface averaged velocity, standard deviation of velocity, and uniformity were chosen as indicators of the design object. A case study showed that two factors, (i) reducing the space between the evaporator and the condenser and (ii) introducing a cover to reduce the by-passing air flow, have the strongest influence on the air distribution in this dehumidifier.

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An Implicitly Balanced Hurricane Model with Physics-Based Preconditioning

Monthly Weather Review ◽

10.1175/mwr2901.1 ◽

2005 ◽

Vol 133 (4) ◽

pp. 1003-1022 ◽

Cited By ~ 32

Author(s):

J. M. Reisner ◽

A. Mousseau ◽

A. A. Wyszogrodzki ◽

D. A. Knoll

Keyword(s):

Linear System ◽

Physical Model ◽

Stokes Equations ◽

Three Dimensional ◽

Solution Procedure ◽

Sound Waves ◽

Time Step ◽

Efficient Manner ◽

First Order ◽

Implicit Approach

A numerical framework for simulating hurricanes based upon solving a nonlinear equation set with an implicitly balanced solution procedure is described in this paper. The physical model is the Navier–Stokes equations plus a highly simplified and differentiable microphysics parameterization package. Because the method is fully implicit, the approach is able to employ time steps that result in Courant–Friedrichs–Lewy (CFL) numbers greater than one for advection, gravity, and sound waves; however, the dynamical time scale of the problem must still be respected for accuracy. The physical model is solved via the Jacobian-free Newton–Krylov (JFNK) method. The JFNK approach typically requires the approximate solution of a large linear system several times per time step. To increase the efficiency of the linear system solves, a physics-based preconditioner has been employed. To quantify the accuracy and efficiency of the new approach against traditional approaches, the implicitly balanced solver was first compared against semi-implicit approaches for the simulation of a precipitating moist bubble. The moist-bubble simulations demonstrated the ability of the implicitly balanced approach to achieve a given level of accuracy in a more efficient manner than either a first-order semi-implicit approach or a traditional leapfrog semi-implicit approach. This behavior is further illustrated in first-of-a-kind three-dimensional implicitly balanced hurricane simulations that reveal the first-order-in-time semi-implicit algorithm needs to take a time step at least 60 times smaller than the implicitly balanced algorithm to produce a comparable accuracy.

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