scholarly journals Universal metric of calculation of mathematical model uncertainty for technological processes and constructions of refrigeration equipment

2016 ◽  
pp. 16-22
Author(s):  
B.M. Menin
Keyword(s):  
Mathematical Model ◽  
Model Uncertainty ◽  
Technological Processes ◽  
Refrigeration Equipment

Classification of mathematical models of technological design

2021 ◽  
pp. 68-71
Author(s):  
Keyword(s):  
Mathematical Model ◽  
Mathematical Models ◽  
Technological Process ◽  
Process Design ◽  
Geometric Parameters ◽  
Technological Design ◽  
Technological Processes ◽  
Technological Preparation

The use of mathematical models is of great importance for the automation of the design of technological processes. Representation of the geometric parameters of the part in the form of mathematical models allows automating the development of the structure and calculation of the parameters of the technological process, which is important for the complete digitalization of the technological preparation of production. Keywords: technological process, design, mathematical model, digitalization. [email protected]

Optimal H∞ Control of Structural Vibrations Using Shape Memory Alloy Actuators

1999 ◽  
Author(s):  
Jian Sun ◽  
Ali R. Shahin
Keyword(s):  
Mathematical Model ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Model Uncertainty ◽  
High Frequency ◽  
Structural Vibrations ◽  
Design Procedures ◽  
Sma Actuators ◽  
Temperature Dynamics ◽  
The Mathematical Model

Abstract This paper investigates robust control problem of structural vibrations using shape memory alloy (SMA) wires as actuators. The mathematical model for these SMA actuators is derived with emphasis in model uncertainty. The linearization of the relation between stress and temperature dynamics of SMA actuators is analyzed for active control. To handle the uncertainties caused by the linearization and the neglected high frequency dynamics, optimal H∞ control was employed to design a controller. An example is used to demonstrate the design procedures and the control system is tested in a nonlinear environment.

scholarly journals Building a mathematical model of technological processes in the acetic acid synthesis reactor

2021 ◽  
Vol 5 (2 (113)) ◽  
pp. 94-104
Author(s):  
Zhanna Samojlova
Keyword(s):  
Mathematical Model ◽  
Acetic Acid ◽  
Acid Synthesis ◽  
Critical Value ◽  
Reaction Mass ◽  
Stationary Mode ◽  
Fisher Criterion ◽  
Technological Processes ◽  
Level Of Significance ◽  
The Mathematical Model

The result of the study reported in this paper is the proposed mathematical model of technological processes occurring in the reactor for acetic acid synthesis. The initial parameters of the reactor considered were the value of the concentration of acetic acid at the reactor outlet, temperature, the level of reaction mass, and pressure in the reactor. The input parameters included the amount of methanol and carbon monoxide supplied. Material and thermal balances of reactor technological processes were used to construct the mathematical model of the reactor. Fisher criterion was applied to test the mathematical model for adequacy. At the specified 5 % level of significance, the value of Fisher criterion for the concentration of acetic acid, temperature, and the level of reaction mass in the reactor does not exceed its critical value for a stationary mode. The reproducibility of the modeling results was tested using the Cochran criterion. The value of the Cochrane criterion, at the predefined 5 % level of significance, for the concentration of acetic acid, temperature, and the level of reaction mass in the reactor does not exceed its critical value for different modes. The relative error for the modeled output parameters was calculated. The relative error of the initial parameters did not exceed the level of 10 %. The model built makes it possible to calculate with satisfactory accuracy the value of the concentration of acetic acid at the reactor output, the temperature and level of the reaction mass in the reactor under a stationary mode. The resulting model could be used to automate the control of technological processes in the acetic acid synthesis reactor under a stationary mode. The study results open additional opportunities to manage the stationary mode of the reactor

scholarly journals МОДЕЛЮВАННЯ ХІМІКО-ТЕХНОЛОГІЧНИХ ПРОЦЕСІВ У SCADA ЗА ДОПОМОГОЮ ТЕХНОЛОГІЇ OPEN PLATFORM COMMUNICATIONS

2020 ◽  
pp. 59-66
Author(s):  
Ігор Леонідович Левчук ◽  
Олег Петрович Мисов ◽  
Ксенія Олексіївна Фесенко ◽  
Антон Романович Шейкус
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Mathematical Models ◽  
Information Exchange ◽  
Raw Materials ◽  
Synthesis Process ◽  
Technological Processes ◽  
Open Platform ◽  
Model Control ◽  
Opc Technology

The subject of study in the article are methods for integrating mathematical models of chemical-technological processes implemented in universal modeling programs into modern SCADA systems for developing and improving methods for controlling these processes. The goal is to develop a control system for the synthesis of acetylene in a kinetic reactor, based on a computer model created in universal modeling programs and integrated into SCADA using open platform communications (OPC) technology. Tasks: to create a mathematical model of the process of synthesis of acetylene based on the selected universal modeling program; to develop a way to integrate the resulting model into modern SCADA using OPC technology; to develop in SCADA a control system for the process of synthesis of acetylene according to a mathematical model as part of a functional human-machine interface and control subsystem algorithms; get transient graphs and prove the efficiency of the control system. Conduct a process study using a mathematical model. The methods used are computer simulation of technological processes; OPC technology; SCADA based management. The following results are obtained. A control system for the acetylene synthesis process based on SCADA Trace-Mode and a mathematical model implemented in the ChemCAD package has been developed, while the model - control system information exchange is implemented based on OPC technology. Checked and proved the efficiency of the resulting control system. A mathematical study of the process was carried out, an experimental dependence of the yield of the final product, acetylene, on the temperature, and consumption of raw materials at the inlet of the reactor was established. Conclusions. The novelty of the results is as follows. A new method is proposed for integrating mathematical models implemented in the ChemCAD modeling package into modern SCADA, based on OPC technology. A study of the process of acetylene synthesis by a mathematical model was carried out, experimental dependences of the acetylene yield on temperature and ethylene consumption at the inlet of the synthesis reactor were obtained. An analysis of the obtained experimental dependences showed the need to use cascade control algorithms to increase the efficiency of controlling the process of acetylene synthesis in a kinetic reactor.

MOVEMENT OF METAL BETWEEN COOLING ROLLS

2020 ◽  
Vol 7 (4) ◽  
pp. 56-72
Author(s):  
Anastasiya Pavlenko ◽  
Keyword(s):  
Mathematical Model ◽  
Water Temperature ◽  
Molten Metal ◽  
Cooling Water ◽  
Thin Metal ◽  
Research Results ◽  
Optimal Ratio ◽  
Technological Processes ◽  
Cooling Water Temperature ◽  
Metal Sheets

The article presents the results of a study of the process of cooling a liquid molten metal on the surface of rotating rolls. A mathematical model is proposed to determine the optimal ratio of the cooling water temperature and the size of the cooling surfaces. The research results can be used to optimize technological processes associated with the production of thin metal sheets.

scholarly journals COMPONENTS OF MATHEMATICAL MODEL OF TEXTILE YARN EXTENSION TO A BREAK IN TECHNOLOGICAL PROCESSES

2019 ◽  
pp. 14-19
Author(s):  
K. S. Sultanov ◽  
S. I. Ismoilova ◽  
S. E. Tulonov
Keyword(s):  
Mathematical Model ◽  
Mathematical Simulation ◽  
Textile Yarn ◽  
Cotton Yarn ◽  
Motion Velocity ◽  
Strain Modulus ◽  
Technological Processes ◽  
Motion Process ◽  
External Forces ◽  
Nonlinear Elastic

The idea that mathematical simulation of the process of textile yarn stretching which reveals new features of its destruction in technological processes is substantiated in the paper. Mathematical model should take into account textile yarn motion velocity in technological processes, acting external forces, and the reliable law of yarn strain under stretching. Secant moduli of cotton yarn strain were determined from experimental diagrams of cotton yarn stretching. A significant nonlinearity of the change in strain modulus depending on the strain value is shown. An account of this factor leads to physically nonlinear laws of cotton yarn strain. Therefore, as the basis of a mathematical model of the motion process, a physically developed nonlinear elastic-viscoplastic law of cotton yarn strain is proposed. The main properties of the proposed law and the methods for determining its support dependencies are discussed. An algorithm for using the law in a mathematical model of the process of yarn strain to a break is proposed.

scholarly journals MODELING OF TECHNOLOGICAL PROCESSES FOR ALGORITHMIZATION OF PROBLEM OF MANAGEMENT OF OIL FIELD TREATMENT FACILITIES

2020 ◽  
Vol 63 (2) ◽  
pp. 84-90
Author(s):  
Tatiana N. Karanevskaia ◽  
Alexander G. Shumikhin
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Water Content ◽  
Residence Time ◽  
Material Balance ◽  
Oil Field ◽  
Practical Significance ◽  
Technological Processes ◽  
Automatic Controllers ◽  
Comparison Of The Results

This article presents mathematical models and calculations of balances of technological processes used for the purposes of design and synthesis of process control algorithms in installations of oil field preparation. Representation of the process in the form of characteristic flow graph and adjacency matrix allows to demonstrate and simplify the calculation of material and thermal balances of multistage technological process. The comparison of the results of calculation of material balance obtained using a specialized modeling system and the equations of the main processes of oil preparation with the experimental data of the current installation is given on the example of the installation of preliminary discharge of formation water. The main reason for the high error of the results is the lack of flow and efficiency of the demulsifier in the models of calculation. The mathematical model of calculation of function of water cut at an exit from installation as the main indicator of quality of preparation of oil is developed. A function of water content was approximated by a second order equation and dependent variable controlling variables – the temperature, rate of the demulsifier and the residence time of the liquid in the apparatus. The flow rate and water content of the liquid is determined by the oil field and does not apply to variable control variables. According to the developed mathematical model, graphs of the dependence of water content on the norm of the demulsifier, the residence time of the liquid in the apparatus and temperature are constructed. The comparison of the results showed an adequate degree of comparability of the regime parameters obtained by the model with the experimental data of the current installation. The practical significance of the work lies in the preparation of recommendations on the parameters of the process, transmitted as input data for design and control system as tasks to operators and automatic controllers.

scholarly journals Model of simulation of the process of formation of functional surfaces of micro-opto-electro-mechanical systems’ components

2020 ◽  
pp. 73-82
Author(s):  
І.Ш. Невлюдов ◽  
О.О. Чала ◽  
О.І. Филипенко ◽  
І.В. Боцман
Keyword(s):  
Mathematical Model ◽  
Technological Process ◽  
Mechanical Systems ◽  
Experiment Planning ◽  
Practical Implementation ◽  
Technological Parameters ◽  
Forming Process ◽  
Technological Processes ◽  
Functional Surfaces ◽  
Functional Components

The subject of the article is to establish the relationships between the parameters of formation the functional surfaces of the substrates of micro-opto-electro-mechanical systems’ (MOEMS) components and their physical and technological parameters. Objectives: to increase the reliability and reproducibility of the received information, reduce the complexity of the technological process of forming, by modeling the dependences of the ratios of physical and technological parameters of forming the functional surfaces of the substrates of MOEMS components for the forming process. The methods are used: methods of experiment planning and computer processing of experimental data, mathematical models, digital computer modeling of technological processes. The following results were obtained: a mathematical model was proposed, which was used to model the influence of physical and technological parameters of the functional surfaces of the substrates of MOEMS components on their formation, with the receipt of prototypes. The results can be used in the development of technological processes of production, as substrates of functional components of MOEMS, and other functional elements for various technological purposes. A mathematical model is obtained, which allows predicting the degree of influence of physical and technological parameters of the technological process on the parameters of formation of functional surfaces of substrates of MOEMS components. Conclusions. The scientific novelty of the results is as follows: a mathematical model that has found practical implementation for computer digital modeling in the development of technological processes for the production of functional surfaces of substrates of MOEMS components is proposed, in which, unlike the existing ones, it is possible to predict the degree of influence of physical substrates of MOEMS components, which allows to plan the process of formation, increase the reproducibility of results and reduce the complexity of the technological process.

Microcrystalline Cellulose from Lignocellulosic Material Activated by Steam Explosion Treatment and Mathematical Modeling of the Processes Accompanying its Preparation

2019 ◽  
Vol 945 ◽  
pp. 911-918
Author(s):  
D.B. Prosvirnikov ◽  
Nail F. Timerbaev ◽  
R.G. Safin
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Microcrystalline Cellulose ◽  
Steam Explosion ◽  
Lignocellulosic Material ◽  
Technological Processes ◽  
Hydrolysis Of

In this paper we propose a mathematical model and an algorithm for calculating the processes accompanying the hydrolysis of a lignocellulosic material activated by steam explosion treatment, the purpose of which is to obtain microcrystalline cellulose (MCC). The calculation of the process is implemented in MathCad and CurveExpert software environments. The obtained modeling results will allow to control the technological processes of continuous delignification and hydrolysis of lignocellulosic material activated by steam explosion treatment and also to automate them.

Sign in / Sign up

Export Citation Format

Share Document