The secrets of FEM and CFD analysis
The latest REEF Shares Knowledge event at the High Tech Campus in Eindhoven organised by the Research & Development division of REEF was held on November 8th 2012. The topics of this evening were FEM analysis and CFD analysis.
After a short introduction Martijn Wubbolts started with the first part of the evening.
He explained what Finite Element Modeling (FEM) is and shared is expertise, experience and insights on where and when to use it. Strength calculations are just a small part of the complete FEM analysis. Understanding what the client wants to know, the boundaries, demands and conditions are essential to a good FEM analysis. Then using the specialized modelling software, which have very user friendly interfaces nowadays, seems straight forward but mistakes with devastating consequences are easily made. Martijn explained what kind common mistakes can be made and how to check for these mistakes. After getting results from your model you need to be able to interpret these results, which requires experience, understanding and mechanical knowledge to be able to do so. And quite often knowledge of regulations and guidelines for different industries and applications need to be known to be able to make and interpret a FEM analysis. Something Femtec is specialized in.
Martijn explained that strength analysis by hand are done often, however that FEM modelling can save time and thereby money.
Senior Structural Engineer
Martijn Wubbolts is a Senior Structural Engineer with extensive experience with FEM analysis and modelling and co-owner of Femtec, a FEM-engineering agency.
Furthermore, more complex problems with for instance non-lineair calculations can only be done using FEM analysis. FEM analysis is only a part of engineering processes, however an essential part. It is used in all different kinds of industries like high tech, machine building, marine & offshore, automotive, structural engineering, oil & gas. Martijn gave us different examples of projects were FEM is used.
After the brake the second part was presented by Tom O’Mahoney. He gave us insight in the world of Computational Fluid Dynamics (CFD). First he explained what CFD is, its correlation with FEM and the differences between the two areas of expertise. In contrast to what most people assume, CFD analysis is not only the study of the flow, temperature and interactions of fluids but the study of all non-solid materials. CFD analysis could involve one phase systems but also multi-phase systems or interactions with solid materials in case of flows through pipes. It is incredibly difficult to describe these flows and interactions properly and accurately. Tom demonstrated the problems and limitations you can encounter with CFD by his PhD research on the application of Large-Eddy Simulation to turbine rim sealing flows, part of the internal cooling systems of jet engines for aircraft. It was too expensive to get the necessary answers by performing controlled and validated experiments and therefore a CFD analysis approach was chosen. However, describing the whole system is virtually impossible, mainly because this requires too much computer processor time or power. Therefore, a limited part of the system is described, but several assumptions needed to make the CFD model. Tom explained why and how these assumptions were made and how this translates to other CFD problems. He also demonstrated why validating CFD results with observed experimental results is essential to determine the validity of the CFD model. The second part of his lecture Tom gave examples of his work with TNO demonstrating the advantages and limits of CFD analysis he encounters daily.
Tom O’Mahoney is a CFD expert with extensive experience with different kinds of CFD applications. He working for the Fluid Dynamics Department of TNO.
The subjects of both speakers was on a high technical level and interactive discussions arose with the speakers and among the visitors which continued even during the brake and afterwards at the informal drinks. Again it was an evening of sharing knowledge and gaining new technical insights. The variety of people and subjects were responsible for the fact that the REEF Shares Knowledge meeting was again a success.
Click here for the presentation of Martijn Wubbolts from Femtec
Click here for the presentation of Tom O'Mahoney from TNO
For questions with regard to FEM analysis please contact us via our FEM knowledge center, a collaboration between REEF and Femtec. Visit our website at: www.femkenniscentrum.nl
For questions with regard to CFD analysis you can contact Yvette van Rijckevorsel, Projectmanager REEF at 040 29 46 888 / firstname.lastname@example.org or Tom O’Mahoney, CFD Scientist TNO Fluid Dynamics at 088 866 44 01 / email@example.com