MOVAK3D
Fundamentals
With MOVAK3D the trajectories of many single particles (atoms, molecules or photons) in a "freely" definable vacuum system are simulated. Although particle-particle collisions also may be modeled, this is done rather rudimentarily. The strengths of MOVAK3D lie in the range of large Knudsen numbers. For conventionally sized vacuum systems, large Knudsen numbers correspond to the high and ultra high vacuum ranges where therefore MOVAK3D is an appropriate tool.
Range of application
Typical systems which MOVAK3D can describe well, are e.g. Vacuum duct, Cryopump and Radiation load inside a cryopump.
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In MOVAK3D the geometry of the real system may be described with a set of parallelograms and triangles, or for model parts having a cylinder symmetry with cones, cylinders, rings, spheres, and "units" modeling el-bows and branching pipes are also available. Each surface element is given one of the attributes "source", "absorbing", "reflecting", "statistically scattering". For cryo panels the relation between "covering" and "ab-sorbing coefficient" may be considered. In the "Monte Carlo simulation" step, a number of particle trajectories are modeled, say 100000. If the model contained merely one source and one absorber, the result of this MOVAK3D calculation is directly the transmission probability. This allows to calculate e.g. the conductances of (possibly complex) systems.
In the design of a cryopump the heat load due to heat radiation from surrounding walls onto parts of the cryopump is often of interest. An optimisation of the pumping efficiency often leads to a higher heat load on helium cooled parts. To investigate this, MOVAK3D offers the possibility to define "reflecting" surfaces for polished components. The particles simulated are photons in this case. Having defined the sources and other surface properties properly, a MOVAK3D calculation evaluates how many photons were absorbed on which surface. This is a direct measure for the heat load on each surface.
MOVAK3D Command Language MCL
MCL is an integrated additive preprocessor for MOVAK3D. It also serves to create MOVAK3D models. The preprocessor MCL actually is a very simple programming language designed entirely to create MOVAK3D models. Using MCL offers advantages e.g. for optimization calculations, when the same model with slight changes must be reproduced and then put into the Monte Carlo simulation with MOVAK3D. Creating these differing models is very easy using MCL, because it is merely necessary to redefine the values of predefined variables and then creating the MOVAK3D input set of data again.
Price MOVAK3D incl MCL: 9.600,-- EUR plus VAT
MOVAK3D is available for Microsoft Windows 2000 / XP and Vista.