scholarly journals Impact of the Mathematical Model Description on the Assessment of the Reliability of Structural Elements

2017 ◽  
Vol 245 ◽  
pp. 062055
Author(s):  
Agnieszka Dudzik
Keyword(s):  
Mathematical Model ◽  
Model Description ◽  
Structural Elements ◽  
The Mathematical Model

Approbation of the Mathematical Model of Adhesive Strength with Viscoelasticity

2019 ◽  
Vol 816 ◽  
pp. 96-101
Author(s):  
Stepan V. Litvinov ◽  
Xuan Zhen Song ◽  
Serdar B. Yazyev ◽  
Artur Avakov
Keyword(s):  
Mathematical Model ◽  
Adhesive Strength ◽  
Adhesive Joint ◽  
Epoxy Resins ◽  
Polymeric Materials ◽  
Critical Value ◽  
Structural Elements ◽  
Long Period ◽  
Tangential Stresses ◽  
The Mathematical Model

Expressed viscoelasticity of polymeric materials which can develop over a long period of time prevents their widespread. Some types of polymers, such as epoxy resins, can be used to connect various structural elements. The destruction in this case can be caused by the growth of tangential stresses in the adhesive joint and their achievement of some critical value τadhezive, at which the adhesive joint is destroyed.

scholarly journals MODELLING OF INTERNAL COMBUSTION ENGINES’ EMISSION THROUGH THE USE OF TRAFFIC FLOW MATHEMATICAL MODELS

Transport ◽  
2011 ◽  
Vol 26 (3) ◽  
pp. 271-278 ◽  
Author(s):  
Raimundas Junevičius ◽  
Marijonas Bogdevičius ◽  
Ádám Török
Keyword(s):  
Mathematical Model ◽  
Traffic Flow ◽  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Flow Speed ◽  
Model Description ◽  
Regression Equations ◽  
Combustion Engines ◽  
Traffic Flows ◽  
The Mathematical Model

Road traffic flows on a straight road segment are modelled in this article. The mathematical model of traffic flows has been constructed by using the method of lumped parameters. CO2, CO, CH, NOx, PM regression equations of internal combustion engines’ (ICE) emission has been developed. The accuracy of regression equations is 0.98÷0.99. The article presents assumptions for constructing the mathematical model, description of the mathematical model and gives simulation results. Traffic flow parameters, such as traffic flow concentration and traffic flow speed are presented as modelling results. ICE emission depending on the concentration and traffic flow speed are presented as well.

scholarly journals A tool for multi-scale modelling of the renal nephron

2011 ◽  
Vol 1 (3) ◽  
pp. 417-425 ◽  
Author(s):  
David P. Nickerson ◽  
Jonna R. Terkildsen ◽  
Kirk L. Hamilton ◽  
Peter J. Hunter
Keyword(s):  
Mathematical Model ◽  
Spatial Scales ◽  
Three Dimensional ◽  
Scale Model ◽  
Model Description ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
One Dimensional ◽  
Multi Scale ◽  
The Mathematical Model

We present the development of a tool, which provides users with the ability to visualize and interact with a comprehensive description of a multi-scale model of the renal nephron. A one-dimensional anatomical model of the nephron has been created and is used for visualization and modelling of tubule transport in various nephron anatomical segments. Mathematical models of nephron segments are embedded in the one-dimensional model. At the cellular level, these segment models use models encoded in CellML to describe cellular and subcellular transport kinetics. A web-based presentation environment has been developed that allows the user to visualize and navigate through the multi-scale nephron model, including simulation results, at the different spatial scales encompassed by the model description. The Zinc extension to Firefox is used to provide an interactive three-dimensional view of the tubule model and the native Firefox rendering of scalable vector graphics is used to present schematic diagrams for cellular and subcellular scale models. The model viewer is embedded in a web page that dynamically presents content based on user input. For example, when viewing the whole nephron model, the user might be presented with information on the various embedded segment models as they select them in the three-dimensional model view. Alternatively, the user chooses to focus the model viewer on a cellular model located in a particular nephron segment in order to view the various membrane transport proteins. Selecting a specific protein may then present the user with a description of the mathematical model governing the behaviour of that protein—including the mathematical model itself and various simulation experiments used to validate the model against the literature.

scholarly journals Features of mathematical modelling in the analysis of console-type structures

2019 ◽  
Vol 97 ◽  
pp. 03036 ◽  
Author(s):  
Viktor Orlov
Keyword(s):  
Differential Equation ◽  
Mathematical Model ◽  
Strain State ◽  
Point Of View ◽  
Classical Approach ◽  
Structural Elements ◽  
Physical Point ◽  
Cantilever Structure ◽  
The Mathematical Model ◽  
Majorant Method

The article deals with the mathematical model of console-type structural elements. The dynamic load is presented as quasi-static one. The differential equation of bending of an object is nonlinear and has movable singular points in which the solution has discontinuity. From a physical point of view, the object will break (collapse) in this place. The application of the majorant method to the solution of the problem allows, in contrast to the classical approach, establishing the boundaries of the solution area and to construct an analytical approximate solution to the problem with a given accuracy. As a result, it’s possible to calculate the displacement at any point of the cantilever structure and estimate the stress-strain state of the object.

scholarly journals MATHEMATICAL MODEL OF THE FUNCTIONING PROCESS OF A RUBBER BUSHING ON THE HOOKE AND SAINT-VENANT ELEMENTS’ BASIS

2019 ◽  
Vol 16 (6) ◽  
pp. 706-716
Author(s):  
D. A. Tikhov-Tinnikov ◽  
V. S. Baradiev ◽  
A. I. Fedotov ◽  
A. V. Alekseev
Keyword(s):  
Mathematical Model ◽  
Optimization Methods ◽  
Force Balance ◽  
Model Description ◽  
Harmonic Mode ◽  
Elastic Suspension ◽  
Power Characteristics ◽  
Operating Modes ◽  
Rubber Bushing ◽  
The Mathematical Model

Introduction. Rubber bushings are important parts of the spring systems of modern vehicles. The properties determine not only the comfort of car movement, but also affect the elastic suspension characteristics. When a bushing is deformed, linear sections appear in characteristics. It is advisable to describe such characteristics using a mathematical model based on the classical elements of Hooke and Saint-Venant. The paper presents a mathematical description of the bushing simulation functioning results, accuracy of approach, areas of application of the mathematical model.Materials and methods. The initial data was the experimental characteristic of a cylindrical automobile rubber bushing, obtained in harmonic mode at the 0.03 to 51 Hz frequency and the 0.4 to 10 mm amplitude. The force balance of the two Hooke elements and one Saint-Venant element interacting with each other determined the mathematical model description. The authors carried out the calculations using numerical and optimization methods.Results. As a result, the authors determined functions characterizing the change in the parameters of the Hooke and Saint-Venant elements from the rubber bushings’ deformation amplitude. Moreover, the authors calculated power characteristics in the form of dependences of the rubber bushing effort and also found quantitative indicators of the reliability of the experimental data approximation by the developed mathematical model.Discussion and conclusions. The analysis of the operating modes shows the possibility of the model application to describe the rubber bushing functioning in a stationary harmonic mode with small and medium strain amplitudes. The simulation results of the Hooke’s and Saint-Venant’s parameters reveals the theoretical prerequisites for the possibility of using the model to calculate the bushing force in an unsteady mode.The authors have read and approved the final manuscript. Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

scholarly journals Mathematical model of Mobile wood chipper with the autonomous power supply from the Stirling engine

2017 ◽  
Author(s):  
Е.М. Онучин ◽  
П.Н. Анисимов
Keyword(s):  
Mathematical Model ◽  
Power Supply ◽  
Regression Models ◽  
Wood Chip ◽  
Stirling Engine ◽  
Structural Elements ◽  
Hydraulic Manipulator ◽  
The Mathematical Model ◽  
Carrier Vehicle

С целью повышения эффективности использования низкокачественной древесины топливного назначения предложено устройство измельчающетранспортной машины для производства сухой топливной щепы. Разработана математическая модель функционирования данной машины при производстве топливной щепы на лесосеке. Предложенное устройство имеет автономное энергообеспечение от газогенераторного двигателя Стирлинга на древесном топливе. Измельчающе-транспортная машина состоит из базовой машины с двигателем внешнего сгорания и газогенератором, рубительного модуля с манипулятором и прицепа с накопительным контейнером-сушилкой щепы. Устройство выполняет функции подачи древесины, её измельчения в щепу, сушки щепы, перемещения по лесосеке и выгрузки произведенной щепы. Математическая модель измельчающе-транспортной машины построена с использованием принципа декомпозиции и состоит из расчётных блоков, связанных между собой. Основные расчётные блоки отражают связанные с работой машины динамические процессы и связанные с сушкой производимой щепы теплотехнические процессы. Вспомогательные расчетные блоки модели обобщенно описывают работу двигателя Стирлинга, газификатора щепы, рубительной установки и манипулятора, и взаимодействие со структурными элементами лесосеки. Математическая модель динамики машины разработана на базе уравнений Лагранжа второго рода. Расчетный блок, моделирующий работу двигателя внешнего сгорания, представляет собой систему дифференциальных уравнений адиабатического анализа термодинамического цикла Стирлинга. Для моделирования процессов сушки щепы в накопительном контейнере машины использованы данные экспериментальных исследований в виде регрессионных уравнений. Разработанная математическая модель функционирования измельчающе-транспортной машины позволяет производить вычислительные эксперименты, определять основные параметры и показатели эффективности её работы. The article deals with the mathematical model of functioning Mobile wood chipper with the autonomous power supply from the Stirling engine for producing of the dry wood chips. It is spoken in detail the design and functioning of this machine on the cutting area. Mobile wood chipper comprise the carrier vehicle with Stirling engine and gasifier, chipper with hydraulic manipulator and trailing unit with containerdrier. The device performs functions of supply of wood, chipping, drying of wood chip, movement on a cutting area and unloadings of the produced wood chip. The mathematical model of the Mobile wood chipper is developed with use of the principle of decomposition and consists of interrelated submodels. The main submodels simulate the dynamic processes associated with operation of the machine and thermotechnical processes associated with drying of the wood chip. Slave submodels generalized simulate the functioning of the Stirling engine, the gasifier, chipper with manipulator, and interaction of machine with the structural elements of a cutting area. The mathematical model of dynamics is developed on the basis of Lagrange's equations. Submodel simulate the functioning of the Stirling engine represents the system of the differential equations of the adiabatic analysis of a thermodynamic Stirling cycle. For modeling of chip drying processes in an accumulative container of the Mobile wood chipper empirical data in the form of regression models are used. The developed mathematical model of functioning of the Mobile wood chipper make possible the computing experiment for determination of its effectiveness.

scholarly journals The desorption of ammonia and carbon dioxide from multicomponent solutions: I. Model description and development

2002 ◽  
Vol 56 (7-8) ◽  
pp. 330-337 ◽  
Author(s):  
Milovan Jotanovic
Keyword(s):  
Mathematical Model ◽  
Gas Phase ◽  
Multicomponent System ◽  
Model Description ◽  
Desorption Process ◽  
Process Gas ◽  
Basic Parameters ◽  
Logical Principle ◽  
Multicomponent Solutions ◽  
The Mathematical Model

A mathematical model of the desorption process based on the synthesised technological topology of the regeneration process gas components NH3 and CO2, was developed. The logical principle methodology of the mathematical modelling of desorption processes was worked out in detail. The mathematical model of the process, including the following: - The synthesized technological scheme of the desorption of components NH3 and CO2, with all the necessary requirements and limitations of the mathematical model; - The relevant multicomponent systems which exist in the process were defined in which the interphase transformation occurs; - The considered units (aparatus) are defined which make up the basic technological topology of the process; - Desorption processes in towers with different types of trays were defined and mathematically described; - The cooling process and condensation of gas phase in a complex multicomponent system was of the gas phase in a complex multicomponent system was defined and mathematically described. Many variants of the process were analyzed by using developed model with the aim of determining the relevant functional dependences between some basic parameters of the process. They will be published in the second part of this study.

DETERMINATION OF PERFORMANCE INDICATORS OF THE TRUCK KrAZ-6510TE

2020 ◽  
pp. 19-26
Author(s):  
Olexandr Pavlenko ◽  
Serhii Dun ◽  
Maksym Skliar
Keyword(s):  
Mathematical Model ◽  
Surface Friction ◽  
Building Structures ◽  
Maximum Torque ◽  
Military Equipment ◽  
Military Vehicles ◽  
Force Magnitude ◽  
Vehicle Mobility ◽  
The Mathematical Model

In any economy there is a need for the bulky goods transportation which cannot be divided into smaller parts. Such cargoes include building structures, elements of industrial equipment, tracked or wheeled construction and agricultural machinery, heavy armored military vehicles. In any case, tractor-semitrailer should provide fast delivery of goods with minimal fuel consumption. In order to guarantee the goods delivery, tractor-semitrailers must be able to overcome the existing roads broken grade and be capable to tow a semi-trailer in off-road conditions. These properties are especially important for military equipment transportation. The important factor that determines a tractor-semitrailer mobility is its gradeability. The purpose of this work is to improve a tractor-semitrailer mobility with tractor units manufactured at PJSC “AutoKrAZ” by increasing the tractor-semitrailer gradeability. The customer requirements for a new tractor are determined by the maximizing the grade to 18°. The analysis of the characteristics of modern tractor-semitrailers for heavy haulage has shown that the highest rate of this grade is 16.7°. The factors determining the limiting gradeability value were analyzed, based on the tractor-semitrailer with a KrAZ-6510TE tractor and a semi-trailer with a full weight of 80 t. It has been developed a mathematical model to investigate the tractor and semi-trailer axles vertical reactions distribution on the tractor-semitrailer friction performances. The mathematical model has allowed to calculate the gradeability value that the tractor-semitrailer can overcome in case of wheels and road surface friction value and the tractive force magnitude from the engine. The mathematical model adequacy was confirmed by comparing the calculations results with the data of factory tests. The analysis showed that on a dry road the KrAZ-6510TE tractor with a 80 t gross weight semitrailer is capable to climb a gradient of 14,35 ° with its coupling mass full use condition. The engine's maximum torque allows the tractor-semitrailer to overcome a gradient of 10.45° It has been determined the ways to improve the design of the KrAZ-6510TE tractor to increase its gradeability. Keywords: tractor, tractor-semitrailer vehicle mobility, tractor-semitrailer vehicle gradeability.

EXPERIMENTAL STUDIES OF CAR PROPERTIES ON A PHYSICAL MODEL

2019 ◽  
pp. 10-16
Author(s):  
Oleksii Timkov ◽  
Dmytro Yashchenko ◽  
Volodymyr Bosenko
Keyword(s):  
Mathematical Model ◽  
Remote Control ◽  
Physical Model ◽  
Model Experiment ◽  
Experimental Studies ◽  
Electrical Energy ◽  
Short Term ◽  
Motor Current ◽  
Memory Card ◽  
The Mathematical Model

The article deals with the development of a physical model of a car equipped with measuring, recording and remote control equipment for experimental study of car properties. A detailed description of the design of the physical model and of the electronic modules used is given, links to application libraries and the code of the first part of the program for remote control of the model are given. Atmega microcontroller on the Arduino Uno platform was used to manage the model and register the parameters. When moving the car on the memory card saved such parameters as speed, voltage on the motor, current on the motor, the angle of the steered wheel, acceleration along three coordinate axes are recorded. Use of more powerful microcontrollers will allow to expand the list of the registered parameters of movement of the car. It is possible to measure the forces acting on the elements of the car and other parameters. In the future, it is planned to develop a mathematical model of motion of the car and check its adequacy in conducting experimental studies on maneuverability on the physical model. In addition, it is possible to conduct studies of stability and consumption of electrical energy. The physical model allows to quickly change geometric dimensions and mass parameters. In the study of highway trains, this approach will allow to investigate the various layout schemes of highway trains in the short term. It is possible to make two-axle road trains and saddle towed trains, three-way hitched trains of different layout. The results obtained will allow us to improve not only the mathematical model, but also the experimental physical model, and move on to further study the properties of hybrid road trains with an active trailer link. This approach allows to reduce material and time costs when researching the properties of cars and road trains. Keywords: car, physical model, experiment, road trains, sensor, remote control, maneuverability, stability.

RESEARCH OF INDICATORS OF A VEHICLE WITH A DIESEL WORKING ON DIESEL AND DIESEL GAS CYCLES USING THE MATHEMATICAL MODEL

2020 ◽  
pp. 14-19
Author(s):  
Serhii Kovbasenko ◽  
Andriy Holyk ◽  
Serhii Hutarevych
Keyword(s):  
Mathematical Model ◽  
Diesel Engine ◽  
Environmental Performance ◽  
Energy Performance ◽  
Dual Fuel ◽  
Fuel System ◽  
Compressed Natural Gas ◽  
Diesel Vehicles ◽  
Diesel Cycle ◽  
The Mathematical Model

The features of an advanced mathematical model of motion of a truck with a diesel engine operating on the diesel and diesel gas cycles are presented in the article. As a result of calculations using the mathematical model, a decrease in total mass emissions as a result of carbon monoxide emissions is observed due to a decrease in emissions of nitrogen oxides and emissions of soot in the diesel gas cycle compared to the diesel cycle. The mathematical model of a motion of a truck on a city driving cycle according to GOST 20306-90 allows to study the fuel-economic, environmental and energy indicators of a diesel and diesel gas vehicle. The results of the calculations on the mathematical model will make it possible to conclude on the feasibility of converting diesel vehicles to using compressed natural gas. Object of the study – the fuel-economic, environmental and energy performance diesel engine that runs on dual fuel system using CNG. Purpose of the study – study of changes in fuel, economic, environmental and energy performance of vehicles with diesel engines operating on diesel and diesel gas cycles, according to urban driving cycle modes. Method of the study – calculations on a mathematical model and comparison of results with road tests. Bench and road tests, results of calculations on the mathematical model of motion of a truck with diesel, working on diesel and diesel gas cycles, show the improvement of environmental performance of diesel vehicles during the converting to compressed natural gas in operation. Improvement of environmental performance is obtained mainly through the reduction of soot emissions and nitrogen oxides emissions from diesel gas cycle operations compared to diesel cycle operations. The results of the article can be used to further develop dual fuel system using CNG. Keywords: diesel engine, diesel gas engine, CNG

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