Glossary
Why simulation?
Testing and calculation are complementary areas for the verification and optimization of constructions. Calculation helps to get better products faster, which can meet the requirements placed on them in terms of function, reliability and price.
Using simulation in the right place reduces your costs!
Our latest customer satisfaction analysis shows that companies that primarily bring new products onto the market will make use of the possibilities of simultaneous engineering which will be involved in product development and process optimization in the future. As various studies have shown, both the total time to market and the total costs for product development are reduced, even if the costs in the development area and in construction initially increase by approx. 50 – 100%.
Finite element method (FEM)
The finite element method (FEM for short) is a numerical calculation method. The problem or the calculation is divided into a finite number of elements. The equations (mostly differential equations) are then solved for each of these elements. The results provide information about the entire calculation. The number of elements determines the accuracy of the overall results. The method is used in engineering both in structural mechanics and in fluid mechanics.
Structural mechanics
Structural mechanics is the calculation of deformations, deflections, and internal forces or stresses within structures, either for design or for performance evaluation of existing structures. It deals with the strength calculation of components, material molded parts, component groups, etc., which consist of solid materials such as steel, aluminum, other metal, plastic, rubber, composite material, concrete, wood, glass or others.
Structural mechanics is a technical discipline in which mechanical solid models are created, the solid components to be examined are subdivided into finite substructures and subjected to external mechanical or thermal loads (using the free-cutting principle in the case of vector-valued and directional quantities). As a rule, the contours of the finite individual elements of the substructures correspond to elementary geometric shapes. The interfaces of the individual elements of the finite substructures can then be used to more precisely calculate sizes and states vertically, tangentially or at an angle to these limits in the interior of the solid-state components and thus to gain information about conditions inside the component. Structural mechanics is an interdisciplinary engineering field, which has applications in mechanical engineering (and in particular in vehicle construction, but also in many other branch disciplines), in construction (and in particular in steel construction), in aerospace technology and in defense technology.
This article is based on the article Structural Mechanics from the free Wikipedia encyclopedia and is licensed under the GNU Free Documentation License. A list of authors is available on Wikipedia.
Flow simulation
Computational fluid dynamics (CFD) is an established method of flow simulation. It aims to solve fluid mechanical problems approximately using numerical methods. The model equations used are mostly Navier-Stokes equations, Euler equations or potential equations. The motivation for this is that important problems such as the calculation of the drag coefficient very quickly lead to non-linear problems that can only be solved precisely in special cases. The numerical flow mechanics then offers a cost-effective alternative to wind tunnel tests.
The internationally used abbreviation CFD has been used since a conference of the AIAA in 1973. The use of CFD as an aircraft design tool was also established there.
This article is based on the article Fluid Mechanics from the free Wikipedia encyclopedia and is licensed under the GNU Free Documentation License. A list of authors is available on Wikipedia.
Adiabat
Adiabat is a term from flow simulation. No heat exchange takes place between adiabatic components and their surroundings.
CAE
CAE is the abbreviation for Computer Aided Engineering and includes all variants of computer support for processes in technology, such as CAD, FEM, CFD, MKS and many more.
Elongation
Elongation is the deformation of a component in relation to the undeformed geometry. Elongation is therefore dependent on the acting force and the material parameters.
Modulus of elasticity
The modulus of elasticity is a material parameter that represents the relationship between elongation and tension during elastic deformation.
Contact
In the area of technical calculation, one speaks of contact when two different components touch and can be moved in one or more directions.
Convection
Convection is the heat transfer through moving particles (liquids and gases). There is no convection in a vacuum.
Creeping
Creeping refers to the time-dependent deformation of a material under a constant load. Creeping must be taken into account especially in the case of permanently loaded metals and plastics.
Laminar flow
A flow is laminar if there are no turbulences during the movement of gas or liquid.
Plasticity
One speaks of plasticity when a component is stressed beyond its elastic limit. These loads create irreversible deformations, the so-called plastic deformations.
Boundary conditions
The boundary conditions are the forces that act on a closed system from the outside. These are e.g. bearings or environmental variables such as pressure and temperature.
Tension
In engineering, tension describes the stress on components and materials. Tension is the force that acts on a certain surface. All materials have a maximum tension, which describes how much the corresponding material can be loaded before it is damaged. The stress is divided into tensile-compressive stress, shearing stress and torsional stress.
Turbulent flow
One speaks of turbulent flow when turbulence of any magnitude occurs in the movement of liquid or gas. The turbulent flow is much more complicated to calculate than the laminar flow.
Solidification
Solidification is the behavior of plastically stressed materials. The mechanical strength changes with the plastic deformation. More or less force is therefore required to further deform the component.
VOF method
The volume-of-fluid method (VOF method) is one of the standard methods for calculating two-phase flows in numerical fluid mechanics. The VOF method uses finite volume discretization, i.e. the model is divided into three-dimensional volume elements (calculation cell), as is the case with conventional CFD simulations. A new variable C is stored in the calculation cell, which represents the volume fraction of a phase within the cell. The value can be between 0 and 1. The physical properties such as density or viscosity are derived from the distribution of the phases. In cells that contain both fluids, these values are averaged. The values are then used to calculate a new velocity field using the Navier-Stokes equations. The VOF method can take additional physical properties into account. These include e.g. surface tension, heat transfer, buoyancy effects and phase change.
Tensile strenght
The tensile strength is the maximum stress determined in the tensile test that a material can withstand (in relation to the original cross-sectional area of the tensile test). It therefore overwrites the maximum load (and thus tension) of a material.
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