Papers by John Batteh:

Title: Integration of complex Modelica-based physics models and discrete-time control systems: Approaches and observations of numerical performance
Authors: Kai Wang, Christopher Greiner and John Batteh
Abstract:As CAE simulations become more complex, the need for computational efficiency increases in order to provide timely solutions and analyses. One facet of this complexity is the integration of multiple software modeling tools and environments in order to utilize the most capable computational technologies for the different features of these complex system models. Physical plant models may be developed in Modelica and require variable step solvers to capture both fast and slow continuum dynamics while discrete time-based control systems may be developed in C-code or Simulink and require fixed time step solvers. Integrating these plant and control models into a single environment can result in computational inefficiencies due to conflicting solver time step requirements. This paper will discuss the integrated modeling of an automotive vapor compression air conditioning system and associated control systems over a dynamic drive cycle, and the associated numerical performance issues discovered, as well as some approaches taken to increase said performance.
Links: Full paper

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Title: Powertrain and Thermal System Simulation Models of a High Performance Electric Road Vehicle
Authors: Massimo Stellato, Luca Bergianti and John Batteh
Abstract:Performance and range optimization of electric vehicles are challenging targets in the design of contemporary automobiles. This paper illustrates that key factors in achieving these targets are the thermal system and the development of the related control logic. Both subjects benefit from the support of modeling and simulation. The paper describes our approach applied to a real case study. The activity is the result of cooperation between Dallara, responsible for the case study, and Modelon, developers of the libraries used to build the simulation model.
Links: Full paper

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Title: A Simulation-Based Digital Twin for Model-Driven Health Monitoring and Predictive Maintenance of an Automotive Braking System
Authors: Ryan Magargle, Lee Johnson, Padmesh Mandloi, Peyman Davoudabadi, Omkar Kesarkar, Sivasubramani Krishnaswamy, John Batteh and Anand Pitchaikani
Abstract:This paper describes a model-driven approach to support heat monitoring and predictive maintenance of an automotive braking system. This approach includes the creation of a simulation-based digital twin that combines models and different modeling formalisms into an integrated model of the braking system that can be used for monitoring, diagnostics, and prognostics. The paper provides an overview of the basic models including Modelica models, reduced order models for various key components of the system model, and controls and sensor models. The simulation results include both baseline results for the system and the results of injecting failures into the system for monitoring and predictive maintenance.
Links: Full paper

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Title: Improved Aerodynamic Prediction Through Coupled System and CFD Models
Authors: Ed Tate, Joaquin Gargoloff, Brad Duncan, Hubertus Tummescheit, John Griffin and John Batteh
Abstract:High accuracy predictions of aerodynamic forces using computational fluid dynamics requires accurate geometry. The aerodynamic forces on the vehicle body affects the vehicle posture or the vehicle position with respect to ground. When a vehicle is cruising, the change in vehicle posture is usually relatively small with respect to the size of a vehicle. However, these small changes in geometry can lead to significant correlation differences in drag and airflow structure. To address this issue, a coupled simulation approach was developed to predict vehicle posture in typical cruise and wind tunnel test conditions. This coupled approach was tested using PowerFLOW and Modelon’s Vehicle Dynamics Library (VDL). In this approach, the aerodynamic forces on the body are used to calculate the movement of the body and geometry. This modified geometry is then used to recalculate the operating aerodynamic forces. The modified geometry shows changes in total force, the distribution of forces, and the structure of the airflow over the vehicle. The results provided by correct geometry under load conditions offer better correlation to test and provide car makers with the improved accuracy to confidently improve real world fuel economy.
Links: Full paper