Karalit

KARALIT CFD 4.0 Full features list

APPS
KARALIT CFD offers 6 APPs specifically designed to simplify the set-up process. These APPs are:

- External Flow: designed for unbounƒded flows (i.e. Aircraft simulations)
- Building Flows: designed for ground confined flows (i.e. Wind forces on buildings, pedestrian comfort)
- Environmental terrain flows: designed for automatically managing geometries provided in .map format
(i.e. Assessment of wind farm site)
- Wind Tunnel: designed to numerically simulate a wind tunnel (i.e. Automotive simulations)
- Internal flows: the computational domain is confined by the STL surface
- Free APP: designed to allow users to freely choose among all Bcs/Physical models provided by KARALIT CFD

SURFACES AND VOLUMES  
- The problem's geometrical definition is provided through SURFACES in form of .STL (StereoLithography) files.
Tools are provided to EDIT, DIVIDE and/or SELECT part of surfaces in order, for example, to enforce BCs.

- VOLUMES can be created or imported into the computational domain (as STL files) in order to impose over them some physical property (i.e. source or sink of momentum or energy, porosity, etc.)

LOCAL GRID REFINEMENT (LGR)
It allows users to generate Cartesian anisotropic meshes with assigned target grid size in normal and tangential to the wall directions. Users can also define how many times the finest mesh layer has to be replicated while moving out of the wall and how many transitional layers have to be used before reaching the grid's base line dimension. An arbitrary number of box or sphere refinement windows can be assigned, as well as symmetry or periodic conditions.

PHYSICAL MODELS
- Turbulence modeling: Spalart & Allmaras, κ-epsilon model
- Porosity volume modeling: Darcy-Forchheimer porosity model
- Porosity surface modeling
- Pseudo Conjugate Heat Transfer (PCHT) model
- Source/Sink of momentum
- Source/Sink of Energy
- Single reference frame rotating flows
- Passive scalar

Three different formulations of the equation of state are available:
- Ideal gas
- Liquid fluid (via isothermal compressibility and thermal expansion coefficients)
- Numerically incompressible fluid (constant density)

BOUNDARY CONDITIONS
The following boundary conditions are available throughout the APPs depending on specific APPs and type of fluid. The Free APP offers full access to all BCs.

WALLS' BCs

- No-slip-adiabatic
- Rotating walls
- Wall with heat transfer
- Constant temperature wall
- Inviscid-adiabatic (slip/symmetry)
- Porous wall
- Diabatic wall with heat transfer
- Diabatic wall with assigned external temperature
- Diabatic wall with assigned heat transfer coefficients
- Atmospheric boundary layer
- Periodic translation and rotation

INLET BCs

- Pressure inlet
- Supersonic inlet
- Total conditions and flow angle
- Mass flow rate and temperature
- Mass flow rate and pressure
- Velocity and temperature

OUTLET BCs

- Pressure outlet
- Supersonic outlet
- Mass flow rate and temperature
- Mass flow rate and pressure

NUMERICAL SCHEMES
The following numerical schemes are available:

1. TIME INTEGRATION METHODS

- Explicit Runge-Kutta (steady and unsteady)
- Implicit Gauss Seidel (steady and dual time step)
- Full access to PETSc library (steady and dual time step)

2. SPATIAL DISCRETIZATION SCHEMES

- Upwind-TVD
- Symmetric-TVD
- First order

BUILT-IN VISUALIZER
Allows to visualize computed solutions in the following form:

- Surface Contour
- Vector plots
- Streamlines
- Iso-surfaces
- Probes

PARALLEL CALCULATION
Allows to run the simulation on an unlimited number of cores

SYSTEM REQUIREMENTS
•    Windows® 7 or superior
•    Fedora™
•    Ubuntu
•    Red Hat Enterprise Linux / CentOS

•    Intel® Pentium® 4, Intel Xeon®, Intel Core™, AMD Athlon™ II, AMD Opteron™, AMD Phenom™, AMD FX™ processor or later*
•    8 GB RAM or higher**
•    10 GB  or higher of free disk space (500 MB free disk space for installation)
•    512 MB DRAM or higher OpenGL-capable graphics card
•    24-bit color setting at 1,280x1,024 or higher screen resolution
•    CD-ROM and DVD-ROM drives are not required: installation via electronic download
•    Web browser
•    Internet connection for web downloads

* 2 GHz CPU speed or higher. For superior performance, KARALIT recommends an Intel Xeon®, or AMD Opteron™ processor, and 24 GB RAM or higher. ** KARALIT recommends settings that allow your operating system to manage virtual memory, as needed. There should always be at least as much free hard disk space as system memory (RAM).

The KARALIT approach, called Direct CFD provides simple fill-in-the-blank Apps to streamline setup for specific industries.

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External Flow App

KARALIT provides two Apps for aerospace external aerodynamic simulations: "External Flow" and "Wind Tunnel". Both customized Apps walk the user through the necessary inputs to set up boundary conditions, flow regime and other parameters. Within minutes, even CFD novices can begin running high-quality simulations.
Sector: Aerospace

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Wind Tunnel App

KARALIT has developed a "Wind Tunnel" App, to help deisgners and CFD analysts during the aerodynamic study of the car. The App can be used for studies of factors such as airflow around car bodies, pressure distribution, turbulence and drag. Users simply enter the parameters for key factors and the app takes over, setting up the boundary conditions for a highly accurate simulation.
Sector: Automotive

Watch App Demo

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Building Flow App - Environmental Terrain Flow App

The "Building Flow" App can be used for build environment applications such as pedestrian comfort outside
of buildings and on walkways, smoke dispersal and fire safety: it can also be used for energy efficiency inside building walls and antennas. Another app, named "Environmental Terrain Flow" App, has been designed to perform a wind site assessment study. As for all KARALIT Apps, setting up the simulation involves only a few minutes of user time to input parameters.
Sector: Build Environment/AEC, Energy

Watch App Demo

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Internal Flow App

KARALIT’s "Internal Flow" App drastically simplifies the setup of complex geometries from automotive, aerospace, Oil&Gas, medical and other sectors. Users work directly on their CAD geometry and, through
the App, enter a few key inputs – such as the boundary conditions, fluid properties and flow regime, going from CAD to simulation in a few minutes.
Sectors: Automotive, Aerospace, Oil&Gas, Medical

Watch App Demo

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	KARALIT CFD PRODUCT BROCHURE The KARALIT approach, called Direct CFD, is based on four basic concepts: 1. Eliminating the tedious and time-consuming meshing process. 2. Providing simple fill-in-the-blank apps. 3. A flexible pricing structure. 4. A personal, one-to-one, responsive technical support: no call centers! Download
	KARALIT CFD FOR AEROSPACE EXTERNAL AERODYNAMICS High lift wings, like the NASA Trapped Wing presented here, are typically used by modern jets in military and commercial applications.  See how KARALIT’s mesh-free, app-driven approach takes you from CAD to CFD simulation in just minutes. Download
	KARALIT CFD FOR AUTOMOTIVE EXTERNAL AERODYNAMICS This simulation is used to investigate body aerodynamics based on a Daimler Benz research model.  Preprocessing takes only seconds and the KARALIT app enables design engineers to set up calculations in a few minutes. Download
	KARALIT CFD FOR PEDESTRIAN COMFORT AND SAFETY When designing a new park, a subway station or other public structures, architects need to go beyond aesthetics to ensure pedestian comfort and safety. Using the power of the Immersed Boundary (IB) method, the urban environment model geometry (STL format) is directly immersed into a background Cartesian grid. Preprocessing takes just seconds, as the user does not have to deal with time-consuming mesh generation! Download
	KARALIT CFD FOR INTERNAL VENTILATION AND HVAC KARALIT CFD is not just an efficient tool to allow architects or civil engineers to easily understand the 3D flow around buildings for predicting comfort indices or pressure distribution on building facades, but it can also be efficiently used to predict 3D airflow and all Heating, Ventilating and Air Conditioning (HVAC) systems in indoor environments. Download
	KARALIT CFD INTERNAL FLOWS IN VALVE APPLICATIONS Valves are used in a variety of engineering disciplines, including aerospace, automotive, oil & gas, transportation, medical and other applications. See how easy it is to set up KARALIT simulations for key performance parameters such as critical valve flow characteristics and the induced torque on the disc. Download
	KARALIT CFD APP DEMO: WIND TUNNEL KARALIT has developed a "Wind Tunnel" App, that can be used for studies of factors such as airflow around car bodies, pressure distribution, turbulence and drag. Users simply enter the parameters for key factors and the app takes over, setting up the boundary conditions for a highly accurate simulation. Watch Video
	KARALIT CFD APP DEMO: BUILDING FLOW The "Building Flow" App can be used for build environment applications such as pedestrian comfort outside of buildings and on walkways, smoke dispersal and fire safety: it can also be used for energy efficiency inside building walls and antennas. As for all KARALIT Apps, setting up the simulation involves only a few minutes of user time to input parameters. Watch Video
	KARALIT CFD APP DEMO: INTERNAL FLOW KARALIT’s "Internal Flow" App drastically simplifies the setup of complex geometries from automotive, aerospace, Oil&Gas, medical and other sectors. Users work directly on their CAD geometry and, through the App, enter a few key inputs – such as the boundary conditions, fluid properties and flow regime, going from CAD to simulation in a few minutes. Watch Video

	KARALIT CFD VALIDATION: ASMO KARALIT simulations using the immersed mesh technique predict the correct trends of flow-field streamlines and Cp distribution on the ASMO idealized car body shape. Download
	KARALIT CFD VALIDATION: AHMED 25 KARALIT'S immersed mesh technique is used to predict the correct distribution and trends of streamlines and velocity fields for the Ahmed Body, a simplified car model for the configuration with 25-degrees slant. Download
	KARALIT CFD VALIDATION: AHMED 35 KARALIT'S immersed mesh technique is used to predict the correct distribution and trends of streamlines and velocity fields for the Ahmed Body, a simplified car model for the configuration with 35-degrees slant. Download
	KARALIT CFD VALIDATION: REMOSA A validation study of KARALIT CFD has been carried out on a pipe line in which a system of valves has been set. Download
	KARALIT CFD DISSERTATION: UNIVERSITA' DEGLI STUDI DI ROMA TORVERGATA "Estimation of the immersed boundary technique for industrial fluid dynamic simulation". Download
	KARALIT CFD DISSERTATION: UNIVERSITA' DEGLI STUDI DI ROMA TORVERGATA "Application of the Ghost Cell Method for monitoring flows". Download
	KARALIT CFD DISSERTATION: UNIVERSITA' DEGLI STUDI DI ROMA TORVERGATA "Fluid Dynamic Optimization of an underground station with the support of the Immersed Boundary KARALIT CFD software". Download
	KARALIT CFD DISSERTATION: UNIVERSITA' DEGLI STUDI DI PERUGIA "Immersed Boundary methodology: an alternative approach to the CFD/3D analysis". Download
	KARALIT CFD POSTER: CNR ISTITUTO DI BIOMETEOROLOGIA The Meditterranec City, Athens, Greece "Application of Measurements and Modelling in an urban space to improve well-being". Download

Papers presenting research on the Immersed Boundary technique:
click on the title to download


"A hybrid immersed boundary CFD approach to oil & gas applications"
M. Mulas, M. Talice, A. N. Grozescu, ASME Turbo Expo 2013 Proceedings

"Immersed boundary technique for turbulent flow simulations"
R. Verzicco, G. Iaccarino, Appl Mech Rev, 2003

"Combined immersed–boundary/finite–difference methods for three–dimensional complex flow simulations"
E.A. Fadlun, R. Verzicco, P. Orlandi, J. Mohd–Yusof, J. of Comp. Phys., 2000

"Direct numerical simulation of the pulsatile flow through an aortic bileaflet mechanical heart valve"
M. D. De Tullio, A. Cristallo, E. Balaras, R. Verzicco, J. Fluid Mech. ,2009

"Effects of non perfect thermal sources in turbulent thermal convection"
R. Verzicco, Phys. of Fluids, 2004

"A ghost-cell immersed boundary method for flow in complex geometry"
Y.H. Tseng, J.H. Ferziger, Journal of Computational Physics, 2003

"Immersed Boundary Methods"
R. Mittal, G. Iaccarino, Annual Review of Fluid Mechanics, 2005

"Ghost Fluid Method for Strong Shock Interactions Part 2: Immersed Solid Boundaries"
S.K. Sambasivan, H.S. Udaykumar, AIAA Journal, 2009

"Adaptation of a k-epsilon Model to a Cartesian Grid Based Methodology"
S.M. Ruffin, Jae-Doo Lee, International J. of Mathematical Models and Methods in Applied Sciences, 2009

"A Cartesian Grid Method with Transient Anisotropic Adaptation"
F. E. Ham, F. S. Lien, and A. B. Strong, Journal of Computational Physics 179, 2002

"Dynamic wall modeling for large-eddy simulation of complex turbulent flows"
M. Wanga and P. Moin, Phys. Fluids, 2002

"Turbulent Wall Model for Immersed Boundary Methods"
F. Capizzano, AIAA Journal, 2011