Tips & Tricks

How to manually set the megawords variable in Rayon?
The Rayon solver occasionally will restart the analysis if the megawords variable is too small. Use these simple instructions to increase/adjust Megawords value.
Ricardo Alvarez Vibro-Acoustics

How to call a script within a script
When using VA One developer's kit and new scripts are being created it is useful to call a script within a script. Here we show you how to achieve this.
Ricardo Alvarez Vibro-Acoustics

SEA - Display energy flow for a subsystem in complex models
In a complex SEA model made out of several subsystems, VA One can be used to display the energy flow to a particular subsystem in a couple of steps, this helps to understand how the energy flows to a receiving subsystem in order to define noise control strategies. One of the steps is to isolate the junctions associated to this subsystem, this will also help to understand / verify the connectivity of the model.
Ricardo Alvarez Vibro-Acoustics

SEA - Virtual Transmission Loss
In a complex SEA model made out of several subsystems, using VA One is possible to extract the transmission loss (TL) of one or various subsystems in a single step. Transmission loss of partitions e.g. walls, floor, windows, enclosures have been studied theoretically and experimentally over many years. Partitions are often inhomogeneous, non-uniform, comprise combinations of different materials, have indeterminate boundary conditions and are subject to sound complex fields. Surprisingly the sound transmission behavior of many plane partitions is quite well represented by a simple model which ignores the boundaries. Sound transmission loss can be used to correlate the vibro-acoustic behavior of simple and/or complex systems.
Ricardo Alvarez Vibro-Acoustics

VA One - FE or SEA- How to map trim thickness for sound package representation
Sound control treatments / Trim ,(e.g. headliners,hood liners, dash panel and floor isolators, etc) have complex shapes with variable thickness, sometimes only CAD parts are available. How can I use this data to create noise control treatments (NCT) in FE and/or SEA models with variable thickness?. In this article it is shown how to create a variable thickness noise control treatment with VA One for SEA and/or FE purposes at the same time. A multiple noise control treatment (MNCT) is created for SEA purposes and multiple FE Faces with the mapped/discrete thicknesses are created for FE purposes,
Ricardo Alvarez Vibro-Acoustics

Find dominant path in SEA models
Statistical energy analysis (SEA) computes the flow of vibrational energy between coupled subsystems by applying principle of conservation of energy. Using conservation of energy power balance equations which govern response of a system. Since it is based on energy flow, path analysis is straight forward. In this article it is described how to extract the dominant path in a complex model using SEA and VA One . As a result the subsystems in the dominant path are displayed in the 3d window (All other subsystems are hidden).
Ricardo Alvarez Vibro-Acoustics

Parallel processing
“To pull a bigger wagon, it is easier to add more horses than to grow a gigantic horse.” This paraphrased quotation nicely expresses the basic concept of parallel processing. The speed of sequential computers has been doubling every eighteen months, according to Moore’s law. However, at any given time, that speed is limited by the state of the art in integrated circuit design and manufacturing. To circumvent that limitation, it is possible to split a given computationally intensive task among multiple processors working simultaneously.
Bohus Ulrych Casting

The manufacturing of sand cores
The manufacturing of iron, steel and non-ferrous castings is achieved using a variety of casting process designs, and most of these involve the use of sand cores which form the internal shape of the casting. A good quality casting requires a good quality core. Dimensional stability, uniform density, strength, hardness and permeability are some of the characteristics that need to be controlled. A good core must have suffi cient strength and hardness to be handled and to resist during the pouring of liquid metal. Suffi cient permeability is also necessary for the escape of gases generated during the casting process. The diff erent manufacturing processes and some of the issues related to core production will be discussed here.
Casting

FLEXlm protection file system
ESI group needs to license, manage and track a variety of licensing options, platform and product dependencies. FLEXlm is one of the only software that is up to this task. A simple, shrinkwrapped license management product would not be powerful and flexible enough to license all ESI products.
Casting

Why it is useful to describe problems in terms of non-dimensional parameters and which ones are the main important in solidification?
A dimensionless quantity is a quantity without any physical units. Such a number is typically defi ned as a product or ratio of quantities which do have units, in such a way that all units cancel. Dimensionless quantities are widely used in the fields of physics and engineering but also in every day life.
Casting