Ansys CFX

CFX4 User Manual, Surface sharpening in free surface flows, Ansys CFX. 

Finite volume or finite element methods will in the authors opinion survive since they are able to deal with arbitrary geometries. For more details on these methods see books by (Zinkiewicz 1997) or (Girault and Raviart 1986). Also common multi-purpose-codes like ANSYS or ANSYS/CFX are based on finite element and finite volume methods. 

In this chapter we will summarize the needed facilities for the physical modelling of the material and the flow conditions, which the chosen CFD-code must provide. We focus on the design of the models in ANSYS/ FLOTRAN and ANSYS/CFX, but the specifications will be kept generally applicable to other commercial codes. 

Computational fluid dynamics (CFD) based on the continuum Navier-Stokes equations Eq. 2 has long been successfully used in fundamental research and engineering design in different fluid related areas. Namrally, it becomes the first choice for the simulation of microfluidic phenomena in Lab-on-a-Chip devices and is still the most popular simulation model to date. Due to the nonlinearity arising from the convention term, Eq. 2 must be solved numerically by different discretization schemes, such as finite element method, finite difference method, finite volume method, or boundary element method. Besides, there are a variety of commercially available CFD packages that can be less or more adapted to model microfluidic processes (e.g., COMSOL (http //www.femlab.com), CFD-ACE+ (http // www.cfdrc.com), Coventor (http //www. coventor.com), Fluent (http //www.fluent.com), and Ansys CFX (http //www.ansys.com). For majority of the microfluidic flows, Re number is... 

The emergence of personal computing toward the end of the 1980s marks the beginning of widespread CFD-based software modeling tools. Such software tools, popular in scientific and engineering communities, are commercial software tools, such as ACE+ Suite, ANSYS CFX , ANSYS Fluent , ANSYS Multiphysics , COMSOL Multiphysics , FLOW-3D , STAR-CD and STAR-CCM+ , and an open-source software tool OpenFOAM . Other CFD-based software tools, such as AVL FIRE or ANSYS Polyflow , are also available on the market, but they are... 

Commercially available discretization methods for solving complex real-world physical systems are predominantly based on finite volume method and finite element method. The most widely used commercial software tools, such as ANSYS Fluent , STAR-CD , and STAR-CCM+ , are based on finite volume method, whereas ANSYS CFX uses finite element-based control volume method. On the other hand, COMSOL Multiphysics is based on finite element method. Both methods have advantages and disadvantages, but nevertheless they give enough comparable computational results with real-world physical systems. 

With the advance of software engineering, commercially available CFD and multiphysics-based software modeling tools, such as ANSYS CFX , ANSYS Fluent , ANSYS Multiphysics , COMSOL Multiphysics , STAR-CD , or STAR-CCM-t , have sophisticated postprocessing and visualization units incorporated in their products. There are also available stand-alone visualization units, such as ANSYS CFD-Post , AVS/Express , EnSight , or Tecplot 360 , developed by software companies with a specialism in visualization software tools. 

At this point we present various conceptual studies for illustrating the coupling between CFD- and FE-simulations. For this reason we use the CFD-software package ANSYS CFX as well as the FE-software ANSYS classic. By considering the welding process, the transition point between solid and liquid is defined by the rapid, jump-wise change of the temperature-depending material data for ... 

Fig. 34. Weld pool geometry and main flow lines calculated by ANSYS CFX . Clearly to see is the Marangoni convection due to the temperature-depending surface tension, (Lee et al., 1998).

Fig. 35. 1st row Temperature distribution calculated with ANSYS CFX . Here the moving heat source is applied within the boundary layer air/steel. 2nd row (/c/t) Temperature distribution imported from CFX to ANSYS classic. 2nd row (right) Calculated voN MiSES stress distribution during welding. 

The NSMEBT has organised different activities (scientific mainly) some examples the international conference Advancements of Medicine and Health Care through Technology - MediTech 2007 (the edition), 2009 (the 2" edition), the training The use of ANSYS-CFX software in medical applications (March 2008 trainer Dr. Andrew Narracot, UK), etc. 

The REAL nozzle flow model was validated with measurements performed on a high-pressure nozzle with nitrogen at a test facility of BASF. The measurements were conducted at inlet pressures of up to 1000 bar [15]. In addition, the calculations agree very accurately with the values in DIN EN ISO 9300 [13], based on many measurements on nozzles performed worldwide at pressures below 200 bar. Moreover, Beune [6] has intensively studied the flow behavior through high-pressure safety valves by numerical simulations with ANSYS CFX. He underlined the precision of the real gas nozzle flow model. In addition, he verified experimentally for a certain valve type that the discharge coefficient of the safety valve in combination with the REAL nozzle flow model can be regarded as constant as is presently stated in EN-ISO 4126-7. 

Use tools required for system layout and design, such as (1) system layout VPE, PDMS CATIA etc (2) core prediction codes, eg, SCALE (3) core and system thermohydraulic codes like ANSYS-CFX, RELAP, and CATHARE etc (4) drawing tools like AutoCAD, CATIA, Corel Designer and (5) documentation tools. 

To execute numerical research of a flow pattern of a current of a stream in programmable complex Ansys CFX. To compare the results of calculations for various flows. To make verification of the data gained by calculation with the data gained in experiment. 

According to this model, the equations of traffic written for each phase, dare in common. The algorithm of calculation of such currents has been offered, in particular, in-process (Menter, 1994), and realized in Ansys CFX. The given model is the most exacting to computing resources of the computer—and to an online storage size, and to speed of the processor. 

Modeling in packet Ansys CFX for calculation of hydrogas kinetics of a scrubber consists of five stages ... 

In preprocessor Ansys CFX, it is necessary to execute a statement of problem which includes the following moments ... 

Process of calculation of a current is carried out before achievement of the set convergence criterion. By default in Ansys CFX, results of calculation of a current remain in the form of a file containing all irrformation on a current, sufficient to renew calculation from last condition. It is possible to specify to the program to keep and intermediate conditions that will allow to visualize to a time history of a pattern of a current. Thus, in a file of results co-ordinates of all knots of a desing grid and value of critical parameters of a current are stored in these knots. 

COMPARISON OF RESULTS ANSYS CFX WITH RESULTS OF EXPERIMENT... 

For the electromechanical coupling of piezoelectric actuator and fluid-membrane coupling, the multifield analysis using multiple code coupling has been conducted in ANSYS. The piezoelectric and fluid models are shown in Fig. 5a. The Multifield simulation results were obtained using MFX-ANSYS/CFX simulation environment. The modal boundary conditions for the fluid-structure interface are shown in Fig. 5b. 

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