Simulation: Reusable digital asset for value creation

It is important to adapt the design to customer demands and wishes by being able to access the right mix of simulation tools.  Simulation is replacing expensive and time-consuming physical testing.

Simulation helps to increase confidence in the virtual validation and verification of any design concepts. Simulation models at the core of the digital twin play a crucial role in reducing the design cycle time. Within the context of the digital twin, simulation acts as a coordination link between the real world and virtual world behavior.

Another dimension of simulation is in the predictive maintenance and reliability assessment. Through the concept of 6 Sigma methodology via simulation activities, reduction of failure during operation/service can be achieved.

 

Component level simulation & digital twin:

Simulation within the context of component level is mainly done to validate and optimise geometry and material suitability of any design, addressing physics of multiple disciplines like mechanical, structural, thermal, electrical, and electromagnetics.  In any electrical connector or E-Mobility charging gun development, for example, it is important to consider different components along with electrical connectors.

The geometry and materials parameters from different components are varied as shown in Figure 01, to optimise for the cost, weights, strength, lifetime, and performance in each stage of product development.

Figure 01, Contour of electric induction |D| [C/m2] for optimisation of the cable assembly insulation
Figure 02, Contour of static simulation to understand deformation of a contact pin

Components simulation may be performed for validating stress or displacement using the static finite element analysis as shown in Figure 02.

Electrical conduction generates heat inside components. In order to design for convective heat transfer or heat dissipation, thermal or thermo structural coupled simulations must be performed. In advanced applications, special coatings that are used on top of electrical contacts to minimise wear between two mating surfaces can be simulated. The simulation involving heat generation and thermal dissipation is used to derive the derating parameter for the current conducting connector.

In our highly competitive day and age, reliability is another key aspect along with product quality. Durability and mating cycle simulation can be achieved by way of post-processing of numerical simulation based on established empirical models from different disciplines. For example, mechanical failures and wear can be estimated using contact stresses from finite element results. Loss of electrical resistivity is calculated from the 1D modeling of electrical contacts. This helps in building a life cycle model and assessing the reliability in connection with the specific contacts. This digital model, coupled with operational data (load conditions, environmental conditions, operation time etc.), can be used as a digital twin for estimating the remaining useful life of the connector. This special and expedient digital service is a much sought after feature by customers to ensure their throughput performance.

The example of a crown spring finite element mesh is shown in Figure 03, which is used to determine the critical location on the mesh elements and allowable deformation before designing a contact pin.

Figure 03, Finite element mesh of a crown spring used in E-Mobility chargers

Apart from the classical usage of simulation, transferrable digital assets under the standard asset administrative shell (AAS) framework are becoming popular. Customers are demanding equivalent digital twin models which are the replication in geometrical, functional, and behavioral terms to a real asset.

 

Conclusion

High fidelity simulation models are the brains of digital twins. The scalable, modular digital twins help all stakeholders perform their duties across the life cycle of a product. Simulation and therefore digital twins are coming to the forefront of design, development, manufacturing, and operation. Soon, compatibility and buy/no-buy decisions will be made based on digital twins ahead of actually experiencing the physical products.