Boundary Conditions

The essence of a physical problem is determined by the type of boundary conditions applied to the system. To obtain a correct and trustworthy solution, the user needs to imagine well the physical side of the phenomenon being analysed, in order to specify boundary conditions corresponding to real conditions affecting the product in its life cycle. The result of solving a study will be fully determined by the composition and parameters of boundary conditions, specified by the user. A solution could be obtained that does not reflect on the essence of the physical phenomenon being analysed, if the user fails to interpret correctly the meaning of mechanical or thermal loads or restraints. Note that the process of designating boundary conditions cannot be totally automated, therefore the user is charged with the responsibility of correctly applying loads and restraints on the system, from the prospective of the physically solvable problem.

 

Loads

The AutoFEM Analysis system supports two types of loads: mechanical loads and thermal loads.

The types of loads depend on the type of the study. Mechanical loads are used for static, frequency and buckling analysis of a problem, thermal loads - for static and  thermal analysis of  a problem.

 

Restraints

The AutoFEM Analysis system supports three types of restraints: full restraint, partial restraint and contact. They can be used for static, frequency and buckling analysis of a problem.

 

Types of studies and boundary conditions

Boundary conditions differ, depending on the type of the physical problem being modelled, as follows.

In the case of the "Static Analysis" problem type, the following represent boundary conditions:

•"Fixture"  (restraint);

•"Contact"  (restraint);

•Plane of Symmentry (restraint);

•"Elastic base" (restraint);

•"Force"  (mechanical load);

•"Pressure"  (mechanical load);

•"Hydrostatic pressure"  (mechanical load);

•"Centrifugal force"  (mechanical load);

•"Acceleration"  (mechanical load);

•"Bearing load"  (mechanical load);

•"Torque"  (mechanical load);

•"Additional mass" (mechanical load);

•"Temperature"  (thermal load).

In the case of the "Frequency Analysis" problem type, the following represent boundary conditions:

•"Fixture"  (restraint);

•"Force"  (mechanical load);

•"Pressure"  (mechanical load);

•"Hydrostatic pressure"  (mechanical load);

•"Centrifugal force"  (mechanical load);

•"Acceleration"  (mechanical load);

•"Bearing load"  (mechanical load);

•"Torque"  (mechanical load).

In the case of the "Buckling Analysis" problem type, the following represent boundary conditions:

•"Fixture"  (restraint);

•"Force"  (mechanical load);

•"Pressure"  (mechanical load);

•"Hydrostatic pressure"  (mechanical load);

•"Centrifugal force"  (mechanical load);

•"Acceleration"  (mechanical load);

•"Bearing load"  (mechanical load);

•"Torque"  (mechanical load).

In the case of the "Forced Oscillations Analysis"  problem type, the following represent boundary conditions:

•"Fixture"  (restraint);

•"Elastic base" (restraint);

•"Force"  (mechanical load);

•"Pressure"  (mechanical load);

•"Hydrostatic pressure"  (mechanical load);

•"Acceleration"  (mechanical load);

•"Bearing load"  (mechanical load);

•"Torque"  (mechanical load);

•"Additional mass" (mechanical load);

•"Mechanical Oscillator" (mechanical load);

In the case of the "Thermal Analysis" problem type, the following represent boundary conditions:

•"Temperature"  (thermal load);

•"Heat Flux"  (thermal load);

•"Convection"  (thermal load);

•"Heat Power"  (thermal load);

•"Radiation"  (thermal load).

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