FEM

When components move quickly and/or are subjected to pressure and temperature loads, high stresses occur, at least locally.

Whereas in the case of pressure vessels the decisive component loads are usually attributable to internal pressure or thermal stresses, in turbomachinery construction many components are additionally subjected to centrifugal forces and other dynamic loads.

In both cases, we believe that the first and most important step in our view is to identify and evaluate the various mechanisms in order to select the right calculation method in a second step. It is important here to keep an eye on the entire process chain and not just concentrate on the quasi-static operating conditions. In the case of pressure vessels, for example, the startup and shutdown process should always be considered in terms of the resulting thermal stresses before a pipe or flange wall thickness is significantly increased as a “simple response” to high component stresses.

Due to our many years of experience in turbine construction and the computational verification of pressure vessels and flange connections, we are familiar with almost all problems from these areas and have accordingly created the necessary tools to solve them.

In addition to classical analytical calculations, the use of FEM and CFD simulations is also part of our daily work. The parallel use of both approaches has double advantages:

The results of the classical analytical calculation are first used to validate the FEM results so that systematic errors are excluded and can later serve as a clear and quickly repeatable stress verification. The results of the FEM simulations allow, on the one hand, a much greater and deeper understanding of the actual component behavior and the loading mechanisms and, on the other hand, a detailed and differentiated assessment of the local stresses.

In the case of repeatable calculations for similar components, the analytical calculations can thus also be adapted to the conditions of the specific components, so that ultimately the purely analytical verification is already sufficient for calculation and evaluation.