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Modelling and simulation is a highly progressive area that can create significant financial savings for companies that use it. Simulations can be used in the production area to analyse or verify certain decisions and conditions, on the basis of which correct measures can be taken. However, modelling is a highly time-consuming and therefore costly process, which narrows its use for decisions in high-priority processes. The content of the article is a description and results of the created tool designed for quick analysis of the workplace using simulation. The entire process of functioning was described through Unified Modeling Language (UML) diagrams. Siemens's Tecnomatix Plant Simulation software was used to create the tool. The tool itself was compared both to the length of creation of the mid-size simulation model and the time variance of model creation in a standard way. The tool can be used to reduce the time needed to create a model that is used to analyse the selected workplace, which ultimately increases the productivity of the simulation expert. (Received in May 2022, accepted in July 2022. This paper was with the authors 1 week for 1 revision.) [ABSTRACT FROM AUTHOR]

Fractal cells were proposed to increase the flexibility of production systems and reduce production costs. Because all fractal cells comprise the same type of machine, they can manufacture any product type. Thus, product batches should not be moved on the factory floor. However, owing to natural wear and tear, machines must be stopped for maintenance, which requires machines from other cells, resulting in unnecessary travel. Therefore, this study aimed to investigate the impact of maintenance management policies on fractal physical arrangements using a simulation model. The results indicate that increasing the number of fractal cells can be advantageous for reducing product displacement and makespan. [ABSTRACT FROM AUTHOR]

It is well known that in an acoustic guitar, the hollow wooden body of the guitar, which forms the resonating chamber, plays an important role in the sound produced. In an electric guitar, the influence of the solid guitar body is not so crucial, yet some influence of the vibroacoustic material properties is expected but has not been scientifically confirmed so far. The aim of the research presented in this paper was to confirm the hypothesis and to investigate the influence of the material used for the solid body of an electric guitar on the final sound image. An experimental numerical model of the electric guitar was created to show how designers can be assisted with a tool that allows them to plan the characteristics of the sound to be produced at the design stage, when the material and shape for the body of the guitar have been determined. In order to develop a relevant numerical model of the electric guitar, we built a test bench to validate the numerical model. The results of the numerical simulation of the decay of the string vibrations as a function of the body material used agree well with the results of the experimental measurements, confirming the adequacy of the numerical model presented. [ABSTRACT FROM AUTHOR]

Vortex pumps are finding increasing use where abrasive fluids in petrochemical applications must be handled when pressure is readily available for transporting mixed materials in pumping applications. Related research on fine particle two-phase flow cannot meet the actual production requirements. Therefore, the characteristics of solid-liquid two-phase flow with high solid-phase content in pumps must be investigated. In this study, a two-stage vortex pump with a high demand for passing and steady ability is designed. The external characteristics of the pump, internal pressure field, velocity field, and solid distribution law are explored through high solid concentration and size changes. Results show that the shear stress transport turbulence model is found to be appropriate for the computational fluid dynamics analysis of the characteristics of the vortex pump well. The particle velocity and pressure at the monitoring point at the tongue of the volute are higher, thereby aggravating the wear. With the increase in particle volume concentration, the energy exchange between the media increases, and the hydraulic loss of the flow field increases. [ABSTRACT FROM AUTHOR]

To explore the migration distribution laws of the cleaning agent of solid powder in industrial ventilation pipelines, a gas-solid flow migration model based on dense discrete phase model (DDPM) was built. Influences of various material injection methods (injection and jetting methods), positions, and directions in the narrowing zone of pipelines based on the migration laws of particulate cleaning agents in the pipelines were analysed. Results demonstrate that under the top injection method in the narrowing zone, the particulate cleaning agent presents obvious flow characteristics along the pipeline walls and cleaning agent concentration distributes unevenly in the pipelines. After the injection method is changed to top jetting, particle concentration remains high at one end near the wall and low at the other end. After changing the mouth from the top of the narrowing zone to the middle section and changing the spraying direction from perpendicular to the mainstream direction to the horizontal, the particle concentration of the cleaning agent reaches uniform distribution near the mouth and at the pipeline ends. Particle concentration in the pipelines is improved significantly. [ABSTRACT FROM AUTHOR]