The simulator BOP (Block Orientend Process Simulator) is a software package for large-scale process simulation. It allows to solve dynamic as well as steady-state problems. Due to an equation-based approach, a wide range of processes as they occur in chemical process industries or other process engineering environments can be simulated.
The modeling language of BOP is a high-level language which supports a hierarchically unit-oriented description of the process model and enables a simulation concept that is based on a divide-and-conquer strategy. Exploiting this hierarchical modeling structure, the generated system of coupled differential and algebraic equations (DAEs) is partitioned into blocks, which can be treated almost concurrently. The used numerical methods are especially adopted to solving large-scale problems on parallel computers. They include backward differentiation formulae (BDF), block-structured Newton-type methods, and sparse matrix techniques.
BOP is implemented under UNIX on parallel computers with shared memory (Cray J90, SGI Origin2000, Compaq AlphaServer) but can also be run on different single processor machines as well as under Windows 2k on PCs. So far it has been successfully used for the simulation of several real-life processes in heat-integrated distillation, sewage sludge combustion or power plant environment for example.
Detailed information: http://www.wias-berlin.de/research/groups/nummath/projects/project1
ClusCorr98® (contact: H.-J. Mucha, phone: +49 30/20372-573)
The statistical software ClusCorr98® performs exploratory data analysis mainly by using adaptive methods of cluster analysis, classification, and multivariate graphics. Typically it aims at the extraction of knowledge from huge samples of numerical and alpha-numerical data. Some of the methods are: model-based cluster analysis, hierarchical clustering, principal components analysis, correspondence analysis.
The software ClusCorr98® is written in Visual Basic for Applications (VBA), formerly Excel's exclusive programming language. Meanwhile VBA is based on object models of various Microsoft Office applications. ClusCorr98® runs under Microsoft Windows taking advantage of the Excel environment.
Please find further information under: http://www.wias-berlin.de/products/ClusCorr98 .
COG (contact: I. Schmelzer, phone: +49 30/20372-463)
COG is a software package for grid generation and geometry description. It allows to generate Delaunay grids with local and anisotropic refinement for arbitrary geometries.
The volume-oriented geometry description allows to describe geometries with implicit functions, pixmaps, voxmaps, grids in a dimension-independent way. They may be combined as unions or intersections and transformed using nonlinear coordinate transformations.
Please find further information under: http://www.wias-berlin.de/cog .
DiPoG, Direct and Inverse Problems for Optical Gratings (contact: G. Schmidt, phone: +49 30/20372-456)
The program package provides simulation and optimization of periodic diffractive structures with multilayer stacks.
The direct solver computes the field distributions and efficiencies of given gratings for TE and TM polarization as well as under conical mounting. The inverse solver deals with the optimal design of the grating geometry, realizing given optical functions, for example far field patterns, efficiency or phase profiles. The algorithms are based on coupled generalized finite/boundary elements and gradient type optimization methods. Please find further information under http://www.wias-berlin.de/research/projects/optik
gltools (contact: J. Fuhrmann, phone: +49 30/20372-560)
gltools has been designed with the needs of numerical analysts in mind. Thus, unlike many other packages available, it can be used to enhance existing codes with interactive or non-interactive graphical output. It enhances the OpenGL API with the following additional functionality:
- multiple independent windows,
- basic interactive handling through mouse and keyboard,
- interactive three-dimensional rendering volume,
- character output,
- high-quality frame dump in encapsulated postscript format,
- MPEG video recording of window contents,
- piecewise linear function rendering on two- and
(landscape view of plane sections, isolevel surfaces, isolines) with an
- universal, callback-based mesh interface.
Please find further information under: http://www.wias-berlin.de/~gltools .
LDSL-tool (Longitudinal Dynamics in Semiconductor Lasers) (contact: M. Radziunas, phone: +49 30/20372-441)
LDSL is a tool for the simulation and analysis of the nonlinear longitudinal dynamics in multi-section semiconductor lasers. This software is used to investigate and to design lasers which exhibit various nonlinear effects such as self-pulsations, chaos, hysteresis, mode switching, excitability, and synchronization to an external signal frequency.
LDSL combines models of different complexity, ranging from partial differential equation (PDE) to ordinary differential equation (ODE) systems. A mode analysis of the PDE system and a comparison of the different models is also possible.
NUMATH (contact: G. Hebermehl, phone: +49 30/20372-562)
NUMATH is a well-documented library of FORTRAN subroutines for solving problems in linear algebra; approximation, interpolation and differentiation of functions; computation of integrals; nonlinear equations; optimization; ordinary differential equations; integral equations; special functions; and partial differential equations.
The hierarchical structure of NUMATH consists of three levels: problem solvers, primary routines, and basic modules and routines for matrix manipulation.
The routines of NUMATH can be tested using the modules of the NUMATH test library.
Please find further information under: http://www.wias-berlin.de/~NUMATH .
pdelib (contact: J. Fuhrmann, phone: +49 30/20372-560)
pdelib is a collection of software components which are useful to create simulators based on partial differential equations. The main idea of the package is modularity, based on a pattern-oriented bottom-up design. Among others, it provides libraries for
- iterative solvers,
- sparse matrix structures with preconditioners and direct solver interfaces,
- simplex grid handling,
- graphical output using gltools and OpenGL,
- user interface based on scripting language lua.
Further, based on the finite volume implicit Euler method, a solver for systems of nonlinear reaction-diffusion-convection equations in heterogeneous one-, two-, and three-dimensional domains has been implemented which is part of the package.
Please find further information under: http://www.wias-berlin.de/~pdelib .
WIAS-HiTNIHS (contact: P. Philip, phone: +49 30/20372-480)
The WIAS-High Temperature Numerical Induction Heating Simulator constitutes a transient simulation tool for the temperature evolution in axisymmetric technical systems that are subject to intense heating by induction. The simulator accounts for heat transfer by radiation through cavities, and it allows for changes in the material parameters due to the rising temperature, e.g., employing temperature-dependent laws of thermal and electrical conductivity. The simulator is designed to deal with complicated axisymmetric setups having a polygonal 2-d projection. The induction coil is allowed to move during the simulation. The software is based on the WIAS program package pdelib for the numerical solution of partial differential equations. WIAS-HiTNIHS has been and is further developed within the project Numerical simulation and optimization of SiC single crystal growth by sublimation from the gas phase supported by the BMBF.
Please find further information under: http://www.wias-berlin.de/research/projects/sic#WIAS-HiTNIHS .
WIAS-SHarP (contact: D. Hömberg, phone: +49 30/20372-491)
Based on pdelib a new software for electron and laser beam surface hardening, called WIAS-SHarP, has been developed. Based on a data bank with material parameters for 20 important steels, it contains routines to describe the phase transition kinetics during one heat treatment cycle. Moreover, it allows for quite general radiation flux profiles and the implementation of two independent beam traces. To facilitate its usage, a Java-based GUI has been developed.
WIAS-TeSCA (contact: R. Nürnberg, phone: +49 30/20372-570)
WIAS-TeSCA is a Two and three dimensional Semi- Conductor Analysis package. It serves to simulate numerically the charge carrier transport in semiconductor devices based upon the drift-diffusion model. This van Roosbroeck system is augmented by a vast variety of additional physical phenomena playing a role in the operation of specialized semiconductor devices, as, e.g., the influence of magnetic fields, optical radiation, temperature, or the kinetics of deep (trapped) impurities.
The strategy of WIAS-TeSCA for solving the resulting highly nonlinear system of partial differential equations is oriented towards the Lyapunov structure of the system which describes the currents of electrons and holes within the device. Thus, efficient numerical procedures, for both the stationary and the transient simulation, have been implemented, the spatial structure of which is a finite volume method. The underlying finite element discretization allows the simulation of arbitrarily shaped two-dimensional device structures.
WIAS-TeSCA has been successfully used in the research and development of semiconductor devices such as transistors, diodes, sensors, detectors, and lasers.
The semiconductor device simulation package WIAS-TeSCA operates in a UNIX environment and is available for a variety of configurations as, e.g., SUN, COMPAQ, HP, SGI, but also for Linux (PowerPC).
For more information please look up: http://www.wias-berlin.de/products/tesca .
WIAS-QW and WIAS-KPLIB (contact: U. Bandelow, phone: +49 30/20372-471)
WIAS-QW in combination with WIAS-KPLIB is a numerical code for the simulation of strained multi quantum well structures. Based upon multiband kp-models it allows to treat band mixing effects, confinement effects, crystal symmetry, and the influence of mechanical strain.
In particular, KPLIB calculates the
- subband dispersion,
- transition matrix elements,
- miniband effects in multi quantum well structures.
In dependence on the sheet carrier densities and the temperature, QW calculates the
- optical response function,
- gain spectrum,
- radiative recombination rate,
- carrier density distributions.
Furthermore, the calculations can be done selfconsistently, comprising pure kp-calculations, but also calculations which include the Hartree-Coulomb potential, obtained from Poisson's equation, as well as density-dependent exchange-correlation potentials, which account for the bandgap-shift--one of the most prominent many-particle effects.