Software Cradle Releases SC/Tetra V8 Desktop Engineering http://www.deskeng.com/articles/aaaxka.htm Software Cradle Releases SC/Tetra V8 General purpose, unstructured grid thermal fluid analysis software enhanced with new features. by DE Editors | Published June 21, 2010 Software Cradle Co., Ltd. has released SC/Tetra V8. SC/Tetra V8  is general purpose, unstructured grid thermal fluid analysis software.  V8 contains many new features in the pre-processor, solver, and post-processor. The most significant new features increase software functionality.     New Analytical Functions Volume of Fluid (VOF) Method. Simulating free surfaces in fluid dynamics usually requires expensive, high-end CFD software. Cradle has developed a new numerical scheme for unstructured grid VOF that does not strictly rely on evaluating mass fluxes through cell interfaces.  Version 8 uses a Lagrangian remap approach that focuses on evaluating the transported volume of fluid.  The volume of fluid transported into a cell results in a volume of fluid occupied in a Lagrangian prototype overlapped into neighbor cells. This approach is stable and robust even on arbitrary meshes, according to the company.  Moreover, Software Cradle says it can evaluate transported volume without errors even through discontinuous boundaries as long as there are no gaps at the boundaries. The unstructured grid VOF method can be applied to incompressible two-phase flows. Six Degrees of Freedom Dynamical Arbitrary Lagrangian Eulerian (ALE).  Traditionally, ALE has been used to simulate active motion of an object  such as rotation of fans, pumps, and turbines, translation of valves and pistons, or combinations of both.  In SC/Tetra V8, ALE can now be used to simulate passive or induced motion of an object in all directions (six-degrees of freedom motion) due to fluid dynamic forces acting on the object   Applications include windmills, water turbines, a fishing weight, an object floating in air or water, or an object floating on water.

Enhanced Particle Tracking Function Enhanced Particle Tracking Function.  This feature is used to simulate spray pattern shapes emanating from spray nozzles (drops and mists).  The purpose of this function is to simulate particle break-up and coalescence.  Two different droplet break-up models can be used: the Taylor Analogy Breakup model based on an analogy between an oscillating and distorting droplet and a spring-mass system, or the Wave Breakup model based on unstable growth analysis of surface waves for a gas-liquid surface.

Enhanced Pre-processor Functionality Fluid Bearing Designer Enhanced Pre-processor Functionality Fluid Bearing Designer.  The SC/Tetra V8 pre-processor offers the option of a fluid bearing designer wizard.  Fluid bearings are widely used for high-speed, high-load rotating machinery such as HDD motors.  Fluid Bearing Designer performs mesh generation and sets the boundary conditions for a fluid bearing analysis.  It is equipped with a special graphical user interface (GUI) that enables creation of a new design and mesh along with the necessary boundary conditions by specifying the parameters requested by the GUI. Automatic Rearrangement of Octant. This function automatically arranges fine and coarse octants.  Its purpose is to simplify octant arrangement.  Octants are refined based on the narrowness of geometrical passages or because significant physical phenomena occurs in a particular region.  The degree of refinement can be adjusted to maintain a target number of elements.  

Improved Prism Layer Insertion Improved Prism Layer Insertion.  This function is used to gradate the number of prism layer elements near the boundaries.  It can be used where severe shape conditions occur.  The method inserts prism layer elements in a stair pattern.   It is also able to smooth regions that contain a different number of prism layers. Improvements in Precision/Speed Enhanced Overset Mesh Function.  This enhancement enables use of parallel computing to reduce computation times for overset mesh computations.  The overset mesh uses overlapping meshes to eliminate mesh stretching and shrinking for moving meshes.  This enhancement also enables analysis of moving meshes for compressible flows and is directly applicable for analyzing cavitation in rotating turbo machinery.

These examples represent just some of the enhanced features of SC/Tetra V8.   Other new enhancements include:   Preprocessor Improved wrapping function with Edge conservation Conservation of surface region and Gap detection Geometry auto-cleaning function Enhanced swept elements generator Parallel processing for mesh generation   Solver Fan model with swirling effects Addition of Spalart-Allmaras turbulence model Output heat balance between regions for convection, radiation and conduction  (VF method only) Improved periodic boundary conditions Improved time step control for thermoregulation model Partitioning large scale models over 250M elements Postprocessor Improved OpenGL emulation FLD file interpolation FLD file trimming Direct output of AVI file Viewpoint tracking for moving objects Extended variable: Age of flow