Virtual prototyping and digital twin

Hybrid and full electric automotive market is strongly increasing the demand for power semiconductor modules. With respect to discrete packages, manufacturing of power modules is more complex and new process parameter, such as module deformation (warpage), assumes a key role for a robust design and to guarantee reliable application. The aim of this paper is to study the warpage behaviour during power module assembly flow by means of dedicated warpage measurement at different process steps. Once highlighted the most impacting process for warpage, a finite element model has been developed to reproduce phenomenology, predicting the induced deformation.

Keywords: Finite element modeling , Manufacturability , Planarity , Power module , Warpage measurement

Si- and SiC-based fast on-board chargers require very special thermal strategies, to ensure high reliability in order to assess long life in harsh environments, such as the automotive one. Indeed, the power losses in the switches may lead to a severe temperature rise in the enclosed cabinet, causing a reduce lifetime of the system. In this paper, we propose a scalable fast charger for automotive applications able to manage a 7 kW power flow. A thermal simulation based on COMSOL Multiphysics is performed in this work. The study allows us to get a realistic evaluation of the higher temperatures reached by the active Si and SiC devices of the converter during the normal operation, at the steady state and at the maximum allowed power.

Keywords: automotive , DC/DC converter , fast charger , LLC , OBC , PFC , thermal simulation

The Silicon Carbide (SiC) semiconductor material is playing a fundamental role in the development of new power modules. Due to its excellent physical properties, the power devices based on this novel compound improve the traction inverter performance in electric vehicles. This work presents a 3D Finite Element Model (FEM) and fluid dynamics simulation to investigate the behavior of a directly cooled SiC module structure. Furthermore, a two-step experimental procedure to thermally characterize the module is also reported. It comprises a calibration and, subsequently, the thermal impedance computation. The proposed FEM model is compared with experimental test results in order to demonstrate its effectiveness.

Belt drives are commonly used in various types of transmissions to link two or more rotating shafts. In order to transmit the motion, an effective grip on the pulley has to be set by imposing a pre-load on the belt. Moreover, the dynamics of the system is strongly affected not only by the geometrical and inertial properties but also by the imposed belt tension force as a functional parameter affecting the vibration characteristics. In the present work, it is presented an integrated methodology, experimental and numerical, to determine the dynamic behaviour of a water pump drive in a high-performance internal combustion engine.

Keywords: Belt , Internal combustion engine , Multibody model , Natural frequency , Vibration modes , Water pump transmission drive

This study aims to evaluates how an adaptive winglet during flight can improve aircraft aerodynamic characteristics of the CRJ700. The aircraft geometry was slightly modified to integrate a one-rotation axis adaptive winglet. Aerodynamic characteristics of the new adaptive design were computed using a validated high-fidelity aerodynamic model developed with the open-source code OpenFoam. The aerodynamic model successively uses the two solvers simpleFoam and rhoSimple-Foam based on Reynold Averaged Navier Stokes equations. Characteristics of the adaptive winglet design were studied for 16 flight conditions, representative of climb and cruise usually considered by the CRJ700. The adaptive winglet can increase the lift-to-drag ratio by up to 6.10% and reduce the drag coefficient by up to 2.65%. This study also compared the aerodynamic polar and pitching moment coefficients variations of the Bombardier CRJ700 equipped with an adaptive versus a fixed winglet.

Keywords: Adaptive , Aerodynamic , Longitudinal , Morphing , OpenFoam , Optimization , Subsonic , Transonic , Winglet

A numerical investigation is conducted in order to identify a PID control loop feedback scheme able to return dynamics augmentation and superior seakeeping characteristics in the application of high speed flying yacht hulls. An existing lumped parameters model based on general unsteady equations of motion is extended and implemented in combination with a regular basic ocean waves model, to conduct parametric studies and predict the overall performances of a specific engine-propelled flying yacht hull, both in calm and rough water conditions. The unsteady behavior of six foiling/maneuvering appendages is investigated, the hydrodynamic characteristics being based on a database generated through the use of computational fluid dynamics methods (CFD) coupled with static/dynamic-mesh schemes. Equations of motion and hydrodynamics are solved numerically by explicit time-integration method. By comparison with control open-loop conditions, the results show the effects of the use of PID controllers in such dynamic systems in terms of seakeeping performances and dynamics augmentation.

Keywords: Flying yacht , Foiling , Hydrodynamic performances , Lumped parameters model , Ocean waves , PID control

This study is focused on the development of longitudinal aerodynamic models for steady flight conditions. While several commercial solvers are available for this type of work, we seek to evaluate the accuracy of an open source software. This study aims to verify and demonstrate the accuracy of the OpenFoam solver when it is used on basic computers (32-64GB of RAM and eight cores). A new methodology was developed to show how an aerodynamic model of an aircraft could be designed using OpenFoam software. The mesh and the simulations were designed only using OpenFoam utilities, such as blockMesh, snappyHexMesh, simpleFoam and rhoSimpleFoam. For the methodology illustration, the process was applied to the Bombardier CRJ700 aircraft and simulations were performed for its flight envelope, up to M0.79. Forces and moments obtained with the OpenFoam model were compared with an accurate flight data source (level D flight simulator). Excellent results in data agreement were obtained with a maximum absolute error of 0.0026 for the drag coefficient, thus validating a high-fidelity aerodynamic model for the Bombardier CRJ-700 aircraft.

Keywords: Aerodynamics , Compressible flow , CRJ-700 aircraft , Incompressible flow , OpenFoam software

Vehicle sideslip angle estimation is still one of the most challenging research topics in the automotive industry. Many papers can be found on this topic, where authors propose varied methods to reach the goal. Which is the most effective? After an extensive literature review, two very different methods have been identified as the most used: Extended Kalman Filter with dynamic model and Artificial Neural Network. In this work a comparison among these methods is presented. A fully instrumented car has been used to gather typical vehicle dynamics data and feed the models required for a model-based design approach. Results showed that each method has either positive aspects or drawbacks.

Due to problems related to environmental pollution and fossil fuels consumption that have not infinite availability, the automotive sector is increasingly moving towards electric powertrains. The most limiting aspect of this category of vehicles is certainly the battery pack, regarding the difficulty in obtaining high range with good performance and low weights. The aim of this work is to provide a simulation tool, which allows for the analysis of the performance of different types of electric and hybrid powertrains, concerning both mechanical and electrical aspects. Through this model it is possible to test different vehicle configurations before prototype realization or to investigate the impact that subsystems' modifications may have on a vehicle under development. This will allow to speed-up the model-based design process typical for fully electric and hybrid vehicles. The model aims to be at the same time complete but simple enough to lower the simulation time and computational burden so that it can be used in real-time applications, such as driving simulators. All this reduces the time and costs of vehicle design. Validation is also provided, based on a real vehicle and comparison with another consolidated simulation tool. Maximum error on mechanical quantities is proved to be within 5% while on electrical quantities it is always lower than 10%.

Keywords: Alternative propulsion , Balance of forces , Electric powertrain , Energy consumption , Energy consumption prediction , Hybrid powertrain , Mathematical modelling , Performance prediction

In the industrial contexts of the digital era, data, information and knowledge should seamlessly flow throughout the product lifecycle, and be available at any time and to any agent acting in the value creation stream. PLM is one of the enabler of this scenario, striving to scale the "cobbler"model - where people, information, resources and processes are perfectly integrated - to modern industrial realities operating with multi-disciplinary teams and world-wide dispersed internal and external resources. Yet, despite many industrial realities has invested in the institutionalization of a PLM system, still approx. 60% of time in the value creation process is wasted in searching and waiting for data, data translation, working with wrong data or reinvention of the existing knowledge. After having analyzed the above scenario in the context of a real big industrial reality operating in the turbo-machinery production for Oil & Gas and Engery markets, the present paper aims to propose a solution introducing a working approach based on the modeling of the knowledge domain relevant to a product and its data model by an OWL-DL ontology, and to present the relevant preliminary results. The final target will be the establishment of an ontology-based domain model as the foundation for a digital, human-machine interoperable, product knowledge and data lifecycle management system to bridge the diverse agents operating in the Product Lifecycle Management.

The use of Topology Optimization techniques has seen a great development since the last decade. The principal contributor to this trend is the widespread use of Additive Manufacturing technologies to effectively build complex and performant structures over different settings. Nevertheless, the use of Topology Optimization in Design for Additive Manufacturing processes is not simple and research aims to fill the gap between theory and practice by evolving at the same time both approaches, workflows, and design software that allow their implementation. Since a strong connection between methodologies and tools exists, this work proposes a method to assess computer-aided design tools or platforms. This can be applied to sustain the key phase for selection and adoption of the computer-aided tools in industrial settings embracing Additive Manufacturing. The workflow for Topology Optimization implementation, the structure of the proposed evaluation approach, and its application, are presented to demonstrate effective usability. The automotive case study is the redesign of internal combustion engine piston to benefit of metal Additive Manufacturing based enhanced product performance. A preliminary finite element model is defined and a Topology Optimization based redesign is concurrently set up through four different commercial computer-based platforms. The method accounting for the assessment of required operations for the design optimization is applied to perform the tools selection phase.

Keywords: Automotive , Computer aided design tools , Design for additive manufacturing , Design methods , Topology optimization

Additive Manufacturing (AM) is a key technology in current industrial transformations thanks to the significant benefits that can bring to high-level sectors. Nevertheless, AM-based design approaches require improvements that are fundamental to exploit the potentials of the technology and reduce the lack of process consistency. This work focuses on integrated Design for Additive Manufacturing (DfAM) approaches for product-process design, to meet both functional and technological targets. The key aspects of process design and issues are summarized and the design method to perform metal AM process optimization is presented. The aim is therefore to minimize process-induced defects and flaws of AM-based manufacturing of metal products, such as residual stress and distortions. The approach consists of industrialization task improvement based on modelling optimization and build optimization sub-phases supported by numerical process simulation. Integration of CAD platforms allows embedding these steps to be performed downstream of the product design, which can be achieved through functional or multifunctional optimization techniques as well (e.g. topology optimization, latticing, graded structures/materials). The design method is finally applied to perform the industrialization phase of a high-performance automotive component. The case study is a formula SAE topology optimized brake caliper to be produced by Selective Laser Melting (SLM) process. Process simulationdriven studies on modelling and build preparation subphases (i.e. orientation definition, supports generation, model distortion compensation) are conducted to support the process design. The study demonstrates the part scale level method's suitability to industrial context to improve industrialization in the redesign of components to be produced by metal AM.

Keywords: Additive manufacturing , Automotive , Design method , Powder bed fusion , Process optimization , Process simulation

In this paper, an efficient and robust Cartesian Mesh Generation with Local Refinement for an Immersed Boundary Approach is proposed, whose key feature is the capability of high Reynolds number simulations by the use of wall function models, bypassing the need for accurate boundary layer discretization. Starting from the discrete manifold model of the object to be analyzed, the proposed model generates Cartesian adaptive grids for a CFD simulation, with minimal user interactions; the most innovative aspect of this approach is that the automatic generation is based on the segmentation of the surfaces enveloping the object to be analyzed. The aim of this paper is to show that this automatic workflow is robust and enables to get quantitative results on geometrically complex configurations such as marine vehicles. To this purpose, the proposed methodology has been applied to the simulation of the flow past a BB2 submarine, discretized by non-uniform grid density. The obtained results are comparable with those obtained by classical body-fitted approaches but with a significant reduction of the time required for the mesh generation.

Keywords: Cartesian adaptive grids , Immersed boundaries , LES simulation

The massive presence of plastic in the oceans, both in the form of large debris and micro-plastic, is raising global concern due to its severe effects on the marine environment and fauna, causing loss of biodiversity and potentially threatening human health. Even though this is due to poor waste management, the great production and consumption of single-use plastic is a significant exacerbating factor. Despite policies and bans can be effective measures, there is also the need to raise consumers' awareness, so they can make more sustainable choices when purchasing, using, and dismissing products. In particular, educating young citizens and encouraging them to engage in pro-environmental behaviors is a fundamental task to reach this goal. In this work, we present Contact from the future, a digital game on plastic pollution for children, to create awareness and stimulate pro-environmental behaviors, discussing the definition of objectives and requirements, as well as the design and development of the application.

Keywords: Human computer interfaces/interactions , Virtual and augmented reality environments , Virtual prototyping

The most effective expression of the 4.0 Era is represented by cyber-physical systems (CPSs). Historically, measurement and monitoring systems (MMSs) have been an essential part of CPSs; however, by introducing the 4.0 enabling technologies into MMSs, a MMS can evolve into a cyber-physical measurement system (CPMS). Starting from this consideration, this work reports a preliminary case study of a CPMS, namely an innovative bioinspired robotic platform that can be used for measurement and monitoring applications in confined and constrained environments. The innovative system is a "soft growing" robot that can access a remote site through controlled lengthening and steering of its body via a pneumatic actuation mechanism. The system can be endowed with different sensors at the tip, or along its body, to enable remote measurement and monitoring tasks; as a result, the robot can be employed to effectively deploy sensors in remote locations. In this work, a digital twin of the system is developed for simulation of a practical measurement scenario. The ultimate goal is to achieve a self-adapting, fully/partially autonomous system for remote monitoring operations to be used reliably and safely for the inspection of unknown and/or constrained environments.

Keywords: 4.0 Era , Monitoring systems , Remote monitoring , Remote sensing , Soft growing robots

Residual stresses induced by the welding processes may, in some cases, result in significant warping and distortions that can endanger the integrity of the welded structures. This document reports an investigation of the welding process to make a dissimilar T‐joint through an advanced Finite Element (FE) modelling and a dedicated laboratory test. The T‐joint consisted of two plates of dissimilar materials, AISI304 and S275JR steels, both having a thickness of 5 mm, welded through a Shielded Metal Arc Welding (SMAW). Thermocouples were used to acquire the temperature variations during welding. In parallel, an FE model was built and the welding process was simulated through the “element birth and death” technique. Numerical and experimental outcomes were compared in terms of temperature distributions during welding and in terms of distortion at the end of the final cooling, showing that the FE model was able to provide a high level of accuracy.

Keywords: Dissimilar materials , Distortions , Element birth and death , Finite element method (FEM) , Residual stresses , Shielded metal arc welding (SMAW) , Simulation , T‐joint

Obstructive sleep apnea syndrome (OSAS) is a sleep disorder that causes pauses in breathing or periods of shallow breathing during sleep. Mandibular advancement devices (MADs) represent a non-invasive treatment for OSAS that has had the highest development in recent years. Nevertheless, literature has not primarily investigated the effects of mandibular advancement. This paper presents a finite element method numerical simulation model for evaluating the stress/strain distribution on the temporomandibular joint (TMJ) and periodontal ligaments caused by advancement devices used for the treatment of OSAS. Results highlight that the mandible lift phase generates significant stress values on TMJ, which cannot be neglected for extended usage of MADs. Furthermore, mandible molar teeth are more loaded than incisor ones.

Keywords: Computer-Aided Design , Finite element method , Mandibular advancement device , Obstructive Sleep Apnea Syndrome , Virtual prototyping

The structural properties of cast aluminum parts are strongly affected by the solidification in the production process. The solidification dynamics determines the Secondary Dendrite Arm Spacing (SDAS), directly affecting the structural strength of the alloy. Simulation techniques enable the integrated design of chassis parts and their production equipment. However, in order to effectively predict the SDAS formation, the simulation models need to be investigated and calibrated. The present research investigates the SDAS formation models and identifies a robust relation to be used in Design by Simulation phases for AlSi7Mg0.3 parts.

Keywords: Integrated design , Low pressure die casting , Secondary Dendrite Arm Spacing , Simulation

Reducing energy/resource consumption in production processes can significantly improve the environmental performance of manufacturing systems. This paper proposes a sustainable manufacturing method and tool and describes its application in a mechanical engineering company which produces automotive components. The tool allows to map the processes/activities and the related resources consumed, assess the efficiency through specific key performance indicators, identify process criticalities and thus set mitigation or improvement strategies.

Keywords: Energy efficiency , Energy management , Resource consumption , Resource mapping , Sustainable manufacturing tool

The ITER Radial Neutron Camera is a diagnostic whose objective is measuring neutron emissivity and fusion power density through an array of detectors placed in collimating structures. The RNC is composed of two subsystems (In-Port RNC and Ex-Port RNC), located in the Equatorial Port 01 of the ITER tokamak. Although the measurements from the RNC are required for ITER D-T phase, its In-Port components must be ready for Assembly phase 2. Consequently, the two subsystems will be delivered at different times. At the current status of the design the In-Port RNC interfaces must be defined, if not fully specified, in order to allow for the subsystem integration in the Port Plug. A thorough assessment of the interfaces of the subsystem with all the diagnostics, plants and services in the port has been made, taking into account the concurrent development of the Equatorial Port 01 and the progress in the design of some of the subsystem components that may affect the identification of interfacing Plant Systems. This paper deals with the process that led to definition of the internal and external interfaces of the In-Port RNC, highlighting the main issues and the solutions adopted to perform integration within the Equatorial Port Plug 01.

Keywords: Integration , Interfaces , Iter diagnostics , Radial neutron camera