Cable-pulley system consists of several segments of cables, winches, and pulleys, which is used in a wide range of engineering applications such as lifting equipment and pulley systems, however its dynamics simulation has been a tough issue in the Modelica community. The absolute nodal coordinate formulation (ANCF) uses global displacements and slopes at nodes to describe the geometry of the deformed body, which allows the derivation of constant mass matrices and zero-valued quadratic velocity dependent centrifugal and Coriolis forces, demonstrating its powerful capacity to model flexible multi-body systems for nearly two decades. This paper presents an object-oriented approach to model cable-pulley system, where flexible cables are discretized using ANCF cable elements. It is compatible with the Modelica Multibody Library by using a unified Frame interface and enables coupled analysis of cables and rigid bodies. The paper provides a rich set of application examples showing the ease and efficiency of the Modelica-based component drag-and-drop modelling way for modelling cable-pulley system.

To increase the efficiency of PEM electrolysis, simulation models are required that accurately describe the system's electrochemical and thermal behavior in a computationally efficient manner and are thus suitable for developing control strategies. Therefore, a pseudo-2D PEM electrolyzer model is presented in this paper, which is a compromise between the previously developed models regarding their model complexity. The electrochemical behavior is described with equations commonly used in the literature and the thermal behavior with correlations for gas-liquid heat transfer. Preliminary validation indicates that the model can describe the electrochemical behavior and thermal dynamics of a PEM electrolysis stack with good accuracy.

System simulations are particularly useful when analyzing complex systems. Simulations are often cheaper and safer than physical tests of the actual system(s) of interest. Models can be additionally created for systems that do not exist to find solutions that are impossible to analyze experimentally in early life-cycle stages. Models used in system simulations require appropriate input data to give results with the required fidelity and, in the end, credibility. Integration is often challenging as each system commonly constitutes contributions from several engineering domains. Relying on relevant open standards for information exchange is seen as a means of mitigation. The results of the presented work encompass a developed methodology that allows Computational Fluid Dynamics (CFD) results to be integrated into a simulator using system identification and open standards. Reduced Order Models (ROMs) are generated based on results from a CFD analysis. These ROMs are coupled to lumped parameter system simulation models through the mechanisms of the System Structure and Parameterization (SSP) and Functional Mock-up Interface (FMI) standards. In addition, several important factors to consider before using the proposed methodology are presented. These include the intended use of the ROM, knowing the flow inside the system, what resources are available, and any potential licensing issues.

Pneumatics is a branch of engineering that deals with the use of pressurized air or gases to create mechanical motion. It involves the study and application of systems and components such as air compressors, valves, cylinders, and actuators to control and transmit power through the use of compressed air.

For highly dynamic events in pneumatic systems, such as

fast switching processes in automation

technology, lumped-parameter simulation is not sufficient to

correctly calculate the pressure build-up in pipes. The propagation and

reflections of different pressure waves and refraction waves cannot be

accounted for by the zero-dimensional models provided by the

Modelica.Fluid library.

Therefore, a method for calculating such events using the finite volume

method is presented in this paper. The library presented in this work, uses

Gudonov's scheme and an arbitrary Riemann-solver and gas model to calculate

the time evolution inside 1D or 2D discretized pneumatic components as

well as systems composed of these components.