Simulation-driven Development Research Articles

A Graph-Based Metadata Model for DevOps in Simulation-Driven Development and Generation of DCP Configurations

With the goal of improving the quality of model-based development and to reduce testing effort, DevOps practices have gained more and more importance. However, most system engineers are not DevOps specialists, and there are a lot of manual steps involved when writing build pipelines and configurations of simulations. For this purpose, an abstract graph-based metadata model is proposed. This allows the autogeneration of scenario descriptions for simulations and code for the build server where the simulation environment is set up and executed. This is demonstrated by applying this process to the DCP standard. In this paper, we will discuss three simple use cases which are motivated by practical problems that arise in complex development environments and how the proposed solutions can be used to tackle them. Detailed descriptions and implementations of the use cases show how the proposed methods can be applied in practice and help solve the described problems. Furthermore, a Python implementation of a DCP master and a simple FMI-to-DCP wrapper are presented in this work.

Numerical Simulation Approach for a Dynamically Operated Sorption-Enhanced Water-Gas Shift Reactor

A dynamically operated sorption-enhanced water–gas shift reactor is modelled to leverage its performance by means of model-based process design. This reactor shall provide CO2-free synthesis gas for e-fuel production from pure CO. The nonlinear model equations describing simultaneous adsorption and reaction are solved with three numerical approaches in MATLAB: a built-in solver for partial differential equations, a semi-discretization method in combination with an ordinary differential equation solver, and an advanced graphic implementation of the latter method in Simulink. The novel implementation in Simulink offers various advantages for dynamic simulations and is expanded to a process model with six reaction chambers. The continuous conditions in the reaction chambers and the discrete states of the valves, which enable switching between reactive adsorption and regeneration, lead to a hybrid system. Controlling the discrete states in a finite-state machine in Stateflow enables automated switching between reactive adsorption and regeneration depending on predefined conditions, such as a time span or a concentration threshold in the product gas. The established chemical reactor simulation approach features unique possibilities in terms of simulation-driven development of operating procedures for intensified reactor operation. In a base case simulation, the sorbent usage for serial operation with adjusted switching times is increased by almost 15%.

SIMULATION-DRIVEN DEVELOPMENT FOR COARSE COMMINUTION PROCESS - A CASE STUDY OF GEITA GOLD MINE, TANZANIA USING PLANTSMITH PROCESS SIMULATOR

AbstractA comminution process is a material size reduction and separation process which is primarily used in the aggregates and the minerals processing industry. Knowledge related to equipment’s operation, raw material properties, operational strategies, control system, maintenance, etc. is needed to design a capable plant. New needs are arising from the industry for existing operational crushing plants such as investigation for improvements, upscaling, and downscaling of the capacity. The paper presents an application of simulation-driven development for a crushing plant in an existing gold processing plant. Due to the change in ore characteristics and the need for optimizing the cost of operation, it is required to investigate the opportunities for improvement and alternative options for downscaling the capacity of the plant. A systematic process for configuring, developing, and evaluating alternative concepts using a process simulation tool is presented. The results show the process of generating knowledge for alternative crushing plant operation settings and how the choices can be selected and eliminated using boundary conditions. The evaluation presents possible improvements and alternative concepts with their opportunities and pitfalls.

Accurate Modeling of Motors Incorporated in Micro-Mobility in Simulation-Driven Development Approach

Accurate Modeling of Motors Incorporated in Micro-Mobility in Simulation-Driven Development Approach

Identification of representative operating conditions of HVAC systems in passenger rail vehicles based on sampling virtual train trips

Simulation-driven development and optimization of heating, ventilation and air-conditioning (HVAC) systems in passenger rail vehicles is of growing relevance to further increase product quality and energy efficiency. However, today required knowledge of realistic operating conditions is mostly unavailable. This work introduces methodologies and tools to identify representative operating conditions of HVAC systems in passenger rail vehicles. First a Monte-Carlo-simulation approach was employed to acquire a large set of close-to-reality HVAC operating conditions based on simulated train trips. Sampling simulated train trips bypassed the issue of unavailability of appropriate real-world data. Furthermore the approach allowed high flexibility in considering HVAC-relevant factors associated to different categories of trains, rail networks, operation profiles and meteorological conditions. Second, algorithms and methodologies such as k-means clustering and an adapted Finkelstein–Schafer statistical method were implemented to identify representative HVAC operating conditions from the sampled dataset. Final results comprise a set of time-independent HVAC operating points with associated frequencies of occurrence (ROC-points) as well as a set of time-domain signals for representative days (ROC-signals). These results are input for stationary or dynamic system-level simulations, which are used to support design decisions. The developed methodology was exemplarily applied to urban/suburban trains in Switzerland.

Modeling and simulation-driven development of embedded real-time systems

The design and development of embedded hard real-time (RT) systems is one of the complex development practices, because of the requirements of criticality and timeliness of these systems. One critical aspect of RT systems is the production of output before specified deadline. Formal methods are promising in dealing with the design issues of these applications, although they do not scale well for complex systems. Instead, Modeling and Simulation (M&S) provides a cost-effective approach to verify the design and implementation details of very Complex RT applications. M&S methods provide dynamic and risk-free testing environments to verify different scenarios, and they are used for feasibility analysis and verification of such systems. Nevertheless, the simulation models are usually discarded in the later phases of the development.We present the application of an M&S-based method referred to as DEVSRT (Discrete EVent System Specifications in Real-Time) to solve the discontinuity between the simulation models and the final embedded application, in this paper. DEVSRT defines explicit deadline notation for DEVS transitions, draws a clear mapping between DEVS transitions and real-time tasks and provides a formal method and tool for integration of simulation models with the associated hardware components.

Service Support System Modelling Language for Simulation-driven Development of Functional Products

A functional product (FP) comprises of an integrated package of hardware and support services sold under a performance-based contract. A barrier to the adoption of FP is the lack of tools for obtaining predictions of availability and support costs during product development. A previous paper by the authors described a simulation-driven development strategy for designing FP that are optimised for functional availability and support costs. This iterative strategy involves representing the FP design in a modelling language; using a software code to automatically generate and analyse a simulation model from this representation to produce detailed performance predictions; and using these predictions as feedback to improve the design. The use of a modelling language facilitates the representation of the design details within the hardware and support system that influence availability and support costs. This includes the maintenance process design, maintenance strategy design and maintenance resource availability design. In this paper, an overview of a modelling language the authors have developed for this purpose is described.

A model for predicting and monitoring industrial system availability

This paper describes the integration of a sensor data stream monitoring system into a proposed functional product model capable of predicting functional availability. Such monitoring systems enable predictive maintenance to be carried out – pre-emptive maintenance that is scheduled in response to imminent hardware failure – and are in widespread use in industry. The industrial motivation for this research is that agreed upon system availability is a critical element of any business-to-business agreement regarding functional sales. Such a model is important when making strategic choices regarding FPs and can be used to develop a high availability product design through simulation-driven development, as well as to provide operational decision support that reflects the current reality to enable optimal availability to be achieved in practice. The proposed model integrates hardware, support system and monitoring system models, and is able to incorporate actual operational data. It has been partly verified based on previous research.