Dynamic Process and Accident Simulations as Tools to Prevent Industrial Accidents

Supercritical fluid extraction (SFE) is a process in which a solute present in a homogeneous mixture is preferentially dissolved by a supercritical fluid (SCF) solvent. SCFs are gases or liquids above their critical points. Under these conditions SCFs exhibit enhanced solvating power, higher selectivities, and other desirable physicochemical properties which makes them particularly good solvents. A dynamic SFE process simulator has been developed by modeling various units of a typical SFE process, and realism of the simulated results is enhanced by accounting for instrument noise, random drifts, transport delays, and analyzer dead times. The process simulator has been compared with operating data from a pilot-scale SFE process and yields good agreement. The dynamic process simulator provides a much needed insight into various process interactions and the nonlinearities that can exist in an integrated, multiunit process

Simulation of Railway Vehicle Dynamics in Universal Mechanism Software

Quantitative risk assessment integrated with dynamic process simulation for reactor section in heavy oil desulfurization process

Plant engineering workflow consists of different phases and engineering disciplines. Dynamic process simulation can be utilized to mitigate risks and improve quality of design in the engineering workflow. Earlier and more extensive utilization of simulation is proposed in this paper using an integrated simulation-assisted engineering workflow. In this paper, basic automation design and tests are conducted in dynamic process simulation software Apros. The basic automation design is delivered to detailed design for implementation. Usually engineering projects utilize multiple non-interoperable software tools requiring significant manual data transfer. Standard engineering data interfaces provide reusable and automatic transfer features for engineering software. In this paper, standard-based integration of automation and simulation engineering is demonstrated by transferring automation design data in PLCopen XML format to detailed design. The integration and its benefits are demonstrated and some limitations and challenges for wider utilization are recognized.

Recently the production of nanowires is attracting many scientists but it also holds many challenges. Many problems including growth mechanisms are still not understood clearly. This paper will show briefly some our experiment results of nanowires (GeO2 and Ga2O3) growth by VLS, the rest of the paper will discuss nanowire growth mechanisms and then showing a developed programme on PC for dynamic simulation of nanowire growth process. This running simulation software for nanowires growth process has contained main mechanisms and we can see directly some physical phenomena concerning growth process by VLS method.

Digital Twin (DT) technology has rapidly matured from pilot projects to integral components of advanced asset management and process optimization in the oil and gas (O&G) industry. This review provides a structured synthesis of the current state of digital twin frameworks, with a focus on offshore and topside gas-processing systems, such as those found on Floating Production Storage and Offloading (FPSO). Emphasis is placed on high-fidelity process simulations and scalable architectures integrating real-time data with advanced analytics. Drawing on over 85 peer-reviewed sources and industrial frameworks, the paper outlines modular DT architectures, encompassing steady-state and dynamic process simulations (e.g., Aspen HYSYS), reduced-order and hybrid machine learning models, co-simulation environments, and advanced equation-of-state packages (e.g., GERG-2008). Special attention is given to compressor map integration, Equations of State (EOS) selection, ISO/IEC standard compliance, and digital thread continuity. Additionally, the review explores economic and sustainability-driven DT implementations, including flare and methane mitigation, ISO 50001-aligned energy optimization, and lifecycle/decommissioning strategies. It concludes with a technical and economic assessment of DT maturity for gas compression facilities, identifying research gaps in standardization, long-term validation, and cybersecurity integration. The insights provided are intended to support decision-makers, engineers, and researchers in deploying scalable, auditable, and high-impact DT solutions across the O&G value chain.

In conjunction with choosing the treatment process for the new wastewater treatment plant of Espoo, Finland (400,000 P.E.), Denitrification-Nitrification (DN) and Step-Feed activated sludge processes were compared in terms of required basin volume and consumption of aeration air and methanol. The comparison was made using dynamic process simulation. The advantages of the step-feed process reported in literature – smaller volume required to treat an equal load or ability to treat a higher load in an equal volume – were questioned. In terms of consumables, the two processes were found practically equal. This is, to the best of our knowledge, the first comparison of these process configurations with dynamic simulation.

The teaching of higher mathematics is fundamentally challenged by its abstract and logical nature, while traditional instructional methods show significant limitations in visualizing and dynamizing core concepts. The rise of artificial intelligence has brought revolutionary breakthroughs to the visualization teaching of higher mathematics, largely due to its powerful capabilities in image generation, natural language interaction, and dynamic simulation. This paper focuses on the application of AI technology in this field and systematically constructs three teaching models, “intelligent diagram generation” “interactive experimental exploration”, and “dynamic process simulation”. These models are supported by in-depth analysis of typical cases such as saddle surfaces, vector fields, and integrals. Furthermore, the paper discusses the theoretical foundations and practical pathways of AI visualization teaching, aiming to provide theoretical guidance for promoting the paradigm shift in higher mathematics education from static abstraction to dynamic intuition.

Time delays in dynamic simulation

According to the relative motion relationship of pantograph-catenary system during train operation, longitudinal, vertical and transverse motion simulation systems are established, and power loading is carried out to complete the complete simulation of dynamic current collection process. The measurement and control system is established based on virtual instrument technology. A number of mechanical and electrical parameters are dynamically tested and evaluated. The experimental results show that the experimental system has good dynamic current collection simulation function and can comprehensively evaluate the dynamic current collection characteristics of pantograph-catenary system.

Dynamic Process and Validation of a Full Localization 250W@4.5K Large Scale Helium Cryogenic Plants

The analysis of dynamic deformation processes is an important task in civil and in mechanical engineering. One main emphasis is set on the derivation of the objects transmission function, represented by systems of ordinary or partial differential equations (“white box”-models). The parametric identification of the initial and boundary conditions and relevant material parameters is one of the new challenges in the application of least-square algorithms. Embedding the investigation of the deformation process in a combination of a theoretical and an experimental system analysis suitable methods are provided with adaptive KALMAN-filtering as central identification tool. In this paper the approach of a full system analysis is shown quantifying a dynamic “white-box”-model for the calculation of thermal deformations of bar-shaped machine elements. The task was motivied from mechanical engineering searching new methods for the precise prediction and computational compensation of thermal influences in the heating and cooling phases of machine tools (i.e. robot arms, etc.). The quantification of thermal deformations under variable dynamic loads requires the modelling of the non-stationary spatial temperature distribution inside the object. Based upon FOURIERS law of heat flow the high-grade non-linear temperature gradient is represented by a system of partial differential equations within the framework of a dynamic Finite Element topology. It is shown that adaptive KALMAN-filtering is suitable to quantify relevant disturbance influences and to identify thermal parameters (i.e. thermal diffusivity) with a deviation of only 0,2%. As result an identified (and verified) parametric model for the realistic prediction respectively simu-lation of dynamic temperature processes is presented. Classifying the thermal bend as the main deformation quantity of bar-shaped machine tools, the temperature model is extended to a temperature deformation model. In lab tests with an aluminium column control measurements show that the identified model can be used to predict the columns bend with a mean deviation smaller than 10 mgon. Consequently the deformation model is a precise predictor and suitable for realistic simulations of thermal deformations under variable dynamic loads. In future our activities will be primarily focussed on applications in industrial manufacturing. 1. Parametric identification of dynamic deformation processes The creation of a realistic parametric dynamic deformation model is directly associated with the task to combine systems of differential equations (theoretical physical model) with empirical measurements. Consequently basic principles of system theory can be adapted to the geodetic deformation analysis. The parametric identification of a dynamic “white box”-model 3rd IAG / 12th FIG Symposium, Baden, May 22-24, 2006

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSimulation of dynamical processes in molecular solidsMichael L. Klein and Laurent J. LewisCite this: Chem. Rev. 1990, 90, 3, 459–479Publication Date (Print):May 1, 1990Publication History Published online1 May 2002Published inissue 1 May 1990https://pubs.acs.org/doi/10.1021/cr00101a002https://doi.org/10.1021/cr00101a002research-articleACS PublicationsRequest reuse permissionsArticle Views215Altmetric-Citations13LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The article presents an accurate mathematical model of an electro-pneumatic drive system for positioning a pneumatic cylinder with a double-acting rod, controlled by PWM and four high speed On/Off pneumatic valves. The main elements of the system are included in the model: screw compressor, high-speed pneumatic valves, pneumatic cylinder with double-out rod, PID controller. A simulation of the pneumatic positioning system was carried out using the Simscape language in MATLAB. The system is built using the Simscape Foundation gas domain, implementing simulations of piston rod displacement. An analysis of the results obtained and the simulation model is performed.

The fourth-order Runge–Kutta method is commonly used to compute the current-voltage characteristics of stacks of Josephson junctions. The calculations are performed for long time intervals, and the results are updated four times at each time step. To reduce the calculation time, this study suggests using a second-order explicit scheme instead of the Runge–Kutta method. Good results are obtained in particular calculations. For all $$n$$, estimates of $$\left\| {{{G}^{n}}} \right\|$$ ensuring the bounded growth of the round errors are proved, where $$G$$ is the layer-to-layer transition operator. A specific feature of the scheme under consideration is that its coefficients depend not only on the grid step size ratio $$\gamma = \tau {\text{/}}h$$ but also on $$\tau $$ ($$\tau {\text{ and }}h$$ are the grid step sizes in $$t$$ and $$x$$). It is proved that, for all $$\gamma \leqslant 1$$, the eigenvalues of the characteristic matrix are within the unit disc ($$\left| {{{\lambda }_{j}}({{e}^{{i\phi }}})} \right| \leqslant 1$$ for all $$0 \leqslant \phi \leqslant 2\pi $$) at a distance $$O(\tau )$$ from the unit circle. The estimation method developed in this study can be used in studying other numerical methods.