STRUCTURAL MECHANICS

EARLY use of advanced FEM simulationsStructural integrity and structural strength simulations with FEM

The structural integrity is a crucial factor for product design. The Finite Element Method (FEM) gives the possibility to investigate the individual technical application for sufficient performance. Additionally, the application of the Finite Element Method is independent of the technical discipline.

The highly experienced team of engineers within S.M.I.L.E. – FEM assists you to answer the most important questions regarding the individual application:

  • Which physical loads are critical for the application?
  • How do the loads act on the structure?
  • Is the dimension of the structure sufficient?
  • Which changes of the design are necessary?
  • Can the material thickness be reduced to save costs?
  • Does the application have undiscovered potential for optimization?

Our engineers perform structural strength analyses according to state of the art methods and relevant regulations for all branches of industry:

  • Shipbuilding, Naval defense and submarines
  • Offshore wind as well as offshore oil and gas
  • Onshore wind
  • Industrial plants
  • Automotive as well as railway and locomotives

In many applications, screw connections are used. We support you from the selection of the right screw connection to the detailed computational proof. Different levels of complexity are possible here.

In the preliminary design phase, overall flange connections can be dimensioned with simplified FE framework calculations. If exact statements about each screw are required, we calculate all forces acting on them with the help of the finite element method and carry out a screw evaluation according to Eurocode. In the case of a desired mechanical engineering evaluation, we carry this out in detail according to VDI.

Usually, Finite Element Simulations are applied when the design of a product is finished. However, this has the disadvantage that changes due to an insufficient performance are very costly. It is therefore recommended to apply FEM simulations at an early stage of the design process to receive feedback about potential weaknesses as well as optimization potential.

A trained engineer assists the design department of our customer during the design phase of the product. This allows a cost efficient discovering of weaknesses and unidentified potential for structural optimization at an early stage.

The development of a new product is complex and expensive. This is in particular for the production and testing of prototypes. Using parameters within the CAD software combined with sensitivity analyses and the simulation of variations within FEM can reduce the effort and costs for prototyping, because important investigations can be performed on the computer.

As an alternative, topology optimization can be applied. Within this method, a possible design space as well as loads and boundary conditions are defined. The flow of the forces through the design space is determined by FEM. Unused material can be detected and removed. This allows finding new and innovative designs for the individual technical application.

After we performed the topology optimization simulation, we rework the resulting structure based on manufacturing constrains. Additionally, we provide geometry files suitable for 3D Printing, of which we can print a model at our or our partner’s facilities.

Existing designs show potential for optimization, too. We identify possible solutions and propose possible implementing. This way, S.M.I.L.E. – FEM helps you to use the entire potential of your product.

In many cases, dynamic effects can be simplified to static calculations by applying resulting accelerations. This leads to a significant reduction of computational effort. If the dynamic effects are significant, we provide our customer with transient simulations. Herein, we consider the vibrational behavior of the structure in the time domain, the influence of material damping, vibration absorbers and nonlinear material properties.

The results can then be assessed in time domain, frequency domain using spectral evaluation or as cumulative results (for example a cumulative plastic strain).

For highly dynamic processes as for example crashes, explosions or shock loadings, we use explicit FEM solver as LS-Dyna. You can find more about this topic under “Explicit Dynamics”.

All technical applications are forced to vibrations: A ship moving in rough seas or forced to vibrate by the main engine and propeller, a locomotive rolling on uneven railways or the foundation of a generator.

We identify the natural frequencies by a modal analysis. This allows preventing the structure from being forced to oscillation close to their natural frequency.

If the exciting spectrum is known, we perform a harmonic response analysis. This simulation can consider single or double elastic mountings and material damping. The result is a transfer function in the frequency domain representing the loss of energy within the structure. This way, the behavior of the structure can be predicted.

A special case is random vibration. Examples are the natural sea state acting on offshore structures or vibrations forced by an uneven railway. For this application, we perform a random vibration analysis. The forcing spectrum is generated by a random generator and the simulation is performed in time domain. The random behavior is observed by statistical procedures.

In many fields of application, steel is replaced by fiber reinforced plastics (FRP). FRP can be used to reduce the weight of the construction. Furthermore, the orthotropic strength and stiffness properties allow considering the flow of load through the structure in the design process. On the other hand, additional failure modes as well as the anisotropic properties enforce a high level of knowledge to simulate the behavior of the structure and to assess the results of the computation.

We at S.M.I.L.E. – FEM assist you in the dimension, design and calculation of components made of FRP. We apply highly specialized tools within the FEM environment to consider the layered structure. Furthermore, we assess the connection between composite structures as well as the connection to steel parts.

Precisely understand relationships.

 

Offshore wind foundation
offshore wind converter platform
Heavy lifting operation

REFERENCES

A selection of our references:

  • Seaborne transportation of a 1018 to STP-buoyl
  • Seaborne transportation of a 2000 to cable carousel
  • Strength analysis and spectrum response analysis of a catwalk of a 18.600 t tanker for navigation in ice
  • Structural and modal analysis of the backstage stairs of the Elbphilharmonie Hamburg
  • Strength analysis of a stretcher platform under shock load for an army medical tank
  • Topology optimization of an anvil for offshore pile driving
  • Structural and modal analysis of 2 onboard exhaust desulfurization plants
  • Static and vibrational simulation of stairs for the application on yachts
  • Global structural strength simulation for ship and offshore structures
  • Global strength calculation of an MPSSU under hydrodynamic lads (read more about this simulation here)
  • Strength analysis of the rig of a three-master sailing ship (read more about this simulation here)
  • Strength simulation of the steel framework of a hall according to the EUROCODE rules
  • Strength calculation according to the EUROCODE of the steel framework of a land work using RSTAB
  • Simulation of the plastic behavior of a swivel under axial and bending load (read more about this simulation here)
  • Strength simulation of the drive trains for wind turbines
  • Strength simulation of a rotor hub for wind turbines
  • Simulation of multiple nacelle covers made of composite-material
  • Strength simulation of multiple foundations on corvettes

S.M.I.L.E. - FEM

GmbH

Winkel 2
D-24226 Kiel / Heikendorf
fon: +49 431 - 210 80 20
fax: +49 431 - 210 80 28


e-mail: info@smile-fem.de