simulation

Simulation of Hybrid Solar Collector Operation in Heat Supply System

The paper focuses on the investigation and the simulation of the efficiency of a hybrid solar collector in a heat supply system consisting of two separate units, namely a heat storage tank and a flat solar collector, which are interconnected by pipelines. The study includes the analysis and calculation of the thermal parameters of the system for one day and the determination of the optimal values of the flow rate of the heat carrier in the solar collector and the mass of the heat carrier in the heat storage tank to achieve maximum thermal efficiency of the system.

SIMULATION MODELING OF WAREHOUSE OPERATIONS OF A TRANSPORT COMPANY

The problems and solutions in the logistics of warehouse operations of the transport company are highlighted. The software for the implementation of the simulation model is defined. Simulation modeling of the functioning of the transport company's composition was carried out. The main stages in the implementation of the simulation model are considered. Created a context diagram for the simulation model and refined it using context diagram decomposition. The stages of creating a simulation model in FlexSim are considered.

RESEARCH ON THE CHARACTERISTICS OF GEAR-CUTTING PROCESSES FOR EXTERNAL AND INTERNAL MESHING USING THE POWER SKIVING METHOD

The results of modelling and investigation of external and internal gear-cutting processes using the power skiving method are presented. The principles of constructing a geometric model of undistorted chip formation are described, based on parameters from which cutting forces are calculated. It is found that, under identical conditions, the cutting force is three times greater when internal gears are cut than when external gears are cut. The influence of this force on the machining error is determined by the gear pitch parameter.

PHILOSOPHICAL HORIZONTS OF VIRTUAL REALITY. Review of: Chalmers, D. (2022). Reality +: Virtual Words and the Problems of Philosophy. New York: W. W. Norton & Company. pp. 503

The review is devoted to the new monograph “Reality +: virtual worlds and problems of philosophy” by the famous philosopher David Chalmers. As can be seen from the title of the book, in it the author examines the philosophical potential of virtual reality for the possible solution of philosophical problems, namely: from ontology (problems of reality and hypotheses about simulation) to values (a good and happy life in virtual reality). 

Modeling and simulation of machined surface layer microgeometry parameters

 The formation of the microtopography of the machined surface is one of the most critical factors in ensuring the effective operating properties of the product. These are indicators such as wear resistance, fatigue strength, provision of friction parameters of moving joints, etc. The most important reason for the formation of microroughness is vibration in the technological surface of the machine-tool-tool-tool-workpiece. This article is devoted to describing a new method of modelling the dynamic processes of machining.

The Modes of the Power Supply Scheme of Own Needs During Start-up of the Power Units With an Additional Working Transformer

The efficiency of operation of power units of powerful thermal and nuclear power plants is largely determined by the reliability of power supply systems for their own needs. The main requirements for such systems are maintaining the required voltage level on the busbars of the distribution charters of their own needs and reduction of the time of forced power outages. Ensuring these requirements by the Ukrainian energy sector is complicated by the fact that most of its power plants are operated for a long time, and their equipment is significantly worn out.

Research and simulation of the machining process of difficult-to-cut materials

Heat-resistant and high-alloy steels and alloys are difficult materials to machine. Optimizing the cutting parameters for such materials is a complex and multi-factorial technological process planning task. The paper describes the method of analysis of loading, thermodynamic and stress-strain state of a workpiece while cutting of typical representative of hard-to-cut materials (chromium-nickel alloy IN718) using finite element simulation. Influence of feed rate on cutting force and temperature in the zone of chip formation is given.

Universal mathematical model of asynchronous machine as an element microgrid in smart grid

An universal mathematical model of an induction machine (IM) has been constructed, taking into account the saturation of the main magnetic circuit of its magnetic core and the active power losses.  The proposed approach to IM modeling expands the abilities of MATLAB / Simulink environment for analysis of the electric power supply systems (microgrid in the smart grid) with the nonlinear elements and dynamic load in abnormal, asymmetric and fault regimes.

Modeling and control of an electromechanical system with a permanent magnet generator and a voltage source converter

In the paper simulation dynamic models for the analysis of characteristics and transients of electromechanical system using a permanent magnet electric generator (PMG) connected to a variable speed fixed pitch wind turbine (WT) and a voltage source converter (VSC) mathematical models are developed. The system supplies a direct current (dc) resistive load through a controlled switch.