scholarly journals Model of the dynamics of a wheeled vehicle for a complex of full-scale-mathematical modeling

2020 ◽  
Vol 1 (4) ◽  
pp. 46-60
Author(s):  
B.B. Kositsyn ◽  
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Real Time ◽  
Block Diagram ◽  
Plane Motion ◽  
Full Scale ◽  
Practical Significance ◽  
Modes Of Operation ◽  
Wheeled Vehicle ◽  
Full Scale Tests

Introduction. The use of the method of full-scale-mathematical modeling in “real time” opens up wide opportunities associated with the analysis of the modes of operation of the “man – vehicle – environment” system, as well as the study of the loading of units and assemblies of vehicles. The existing research complexes of full-scale mathematical modeling are suitable for obtaining most of the indicators usually determined by full-scale tests. The difference lies in the ability to fully control the course of virtual testing, recording any parameters of the vehicle movement, taking into account the “human factor”, as well as complete safety of the experiment. Purpose of research. The purpose of this work is to create a mathematical model of the dynam-ics of a wheeled vehicle, suitable for use in such a complex of full-scale mathematical modeling and assessment of the load of transmission units in conditions close to real operation. Methodology and methods. The proposed model is based on the existing model of the dynamics of a wheeled vehicle developed at Bauman Moscow State Technical University. Within the framework of the model, the dynamics of a vehicle is described as a plane motion of a rigid body in a horizontal plane. The principle of possible displacements is applied to determine the normal reac-tions of the bearing surface. The interaction of the wheel with the ground in the plane of the support base is described using an approach based on the “friction ellipse” concept. To enable the driver and operator of the full-scale mathematical modeling complex to drive a virtual vehicle in “real time” mode, the mathematical model is supplemented with a control system that communicates between the control parameter set by the driver by pressing the accelerator and brake pedals and the control actions of the vehicle's transmission units, such as: an electric machine, an internal combustion en-gine, a hydrodynamic retarder and a brake system. The article presents a block diagram of the de-veloped control algorithm, as well as approbation of the system's operation in a complex of full-scale mathematical modeling. Results and scientific novelty. A mathematical model of the dynamics of a wheeled vehicle was developed. It opens up wide possibilities for studying the modes of operation of the “driver-vehicle-environment” system in “real time”, using a complex of full-scale mathematical modeling. Practical significance. A mathematical model of the dynamics of a wheeled vehicle was devel-oped. It is supplemented with an algorithm for the distribution of traction / braking torques between the transmission units, which provide a connection between the driver's pressing on the accelerator / brake pedal and the control parameters of each of the units.

scholarly journals MATHEMATICAL MODELING OF FIRE DEVELOPMENT IN A THREE-STOREY RESIDENTIAL BUILDING DURING FULL-SCALE FIRE TESTS

Fire Safety ◽  
2020 ◽  
Vol 36 ◽  
pp. 121-130
Author(s):  
T. Shnal ◽  
S. Pozdieiev ◽  
R. Yakovchuk ◽  
O. Nekora ◽  
S. Sidnei
Keyword(s):  
Mathematical Modeling ◽  
Calculated Data ◽  
Residential Building ◽  
Full Scale ◽  
Building Structures ◽  
Fire Tests ◽  
Simulation Results ◽  
Full Scale Tests ◽  
Simulator Program ◽  
Story Building

The aim of the work was mathematical modeling of fire development in a three-storey residential building during full-scale fire tests; research of accuracy and reliability of parameters of temperature modes of fire in separate rooms of the building. To achieve this goal, it is advisable to use computational gas-hydrodynamics, which allow to determine the limits of application of this approach to predict the behavior of building structures in a fire. The Pyrosim computer system, which serves as a user shell for the Fire Dynamics Simulator program, was used to calculate the temperature in fire room models. This FDS system uses numerical algorithms to solve the complete system of Navier-Stokes differential equations to determine temperature and other hazards in a fire. To visualize the results of calculations, the software module of the PyroSim Smokeview system was used, which allows to build appropriate graphical representations of temperature distributions.A numerical experiment was performed to model full-scale tests of rooms with fire in a three-story building using computer gas-hydrodynamics methods. The nature of the fire and the time dependences of its main parameters were revealed, which in turn allowed to analyze the adequacy of the simulation results and investigate their adequacy and accuracy.The obtained results of research on the accuracy of modeling of full-scale tests of rooms with fire in a three-story building showed that the error determined when comparing experimental and calculated data was not significant. The relative error did not exceed 28%, and the standard deviation did not exceed 51 ° C. The values of the statistical criteria of Cochren, Student and Fisher for the simulation results due to the difference between the calculated and experimental data have values of no more than 0.98, 0.84 and 1.008, respectively, and do not exceed the tabular values. This means that the simulation results are adequate, which allows you to use this approach to predict the behavior of building structures in a fire that is close to real.

scholarly journals MODELING OF PHOSPHORUS PRODUCTION PROCESSES AND DEVELOPING A MANAGEMENT STRUCTURE BASED ON GREY SYSTEMS

2021 ◽  
Author(s):  
Nigina Toktasynova ◽  
◽  
Batyrbek Suleimenov ◽  
Yelena Kulakova ◽  
◽  
...  
Keyword(s):  
Mathematical Model ◽  
Predictive Model ◽  
Real Time ◽  
General Structure ◽  
Sinter Machine ◽  
Forecast Model ◽  
Practical Significance ◽  
Time Data ◽  
Vacuum Chambers ◽  
Model Based

The agglomeration process is one of the complex, multidimensional technological processes; it takes place under conditions of a large number of disturbing influences. As a result, the amount of return during sintering reaches 40-50%. The work is devoted to the development of a mathematical model capable of predicting and controlling the sintering point based on real-time data. As the main parameters for the construction of predictive models, data measured in real time were used – the temperature in the vacuum chambers and the gas velocity determined through the measured pressure (rarefaction) in the vacuum chambers. This paper describes the methodology and basic algorithms for modeling agglomeration processes, starting from the ingress of the charge into the sinter machine and ending with the production of a suitable agglomerate. The obtained curves of the developed mathematical model of temperature in vacuum chambers served as the basis for testing the forecast model based on the use of the theory of gray systems and the optimization algorithm of the "swarm of particles". Based on the developed mathematical model, a system for predicting the sintering point is constructed, which is the basis for determining the quality of the agglomerate, which will reduce the return volume during sintering. The general structure of the sinter control system based on a dynamic predictive model is also proposed. The practical significance of the developed predictive model based on the theory of gray systems is as follows: - forecast of the sintering point value of the agglomerate and synthesis of the control action based on the forecast; - the algorithm for constructing a mathematical model of the forecast can be used for any process that has the character of a "gray exponential law".

IMPROVEMENT OF THE DIFFRACTION EFFICIENCY OF SPECKLE INTERFEROGRAMS BY SELECTING A METHOD OF MANIFESTATION AND DEVELOPER FOR PRACTICAL USE IN EXPERIMENTAL MECHANICS

2019 ◽  
Vol 6 (2) ◽  
pp. 11-15
Author(s):  
Nyan Min Htet Min Htet ◽  
Igor Valentinovich Volkov
Keyword(s):  
Stress Concentration ◽  
Diffraction Efficiency ◽  
Exposure Time ◽  
Holographic Interferometry ◽  
Full Scale ◽  
Practical Significance ◽  
Concentration Zone ◽  
Full Scale Tests ◽  
Selection Of

This article presents a qualitatively new developed technology of out-of-band registration of speckle holograms in the study of deformations in the concentration zone on samples with holes. Summary. One of the most important aspects of speckle-holographic interferometry is the quality of the resulting speckle-hologram, which largely determines its diffraction efficiency. In this case, the improvement of diffraction efficiency in solving practical problems is carried out through the selection of the developer of photographic plates, the installation of a certain exposure time and the choice of methods for processing photographic plates. However, in practice, there are often problems of obtaining the maximum diffraction efficiency of holograms. We made a choice of developer, exposure time, as well as methods of photo processing of speckle holograms in colliding beams in the process of practical experiment. Practical significance. The technology of out-of-band registration of speckle holograms described in the article can be used in the process of research of SSS of full-scale aircraft structures in areas of stress concentration, as well as their detection during industrial full-scale tests.

ELF OCEAN - Full Scale Tests And Mathematical Model

1971 ◽  
Author(s):  
J.P. Bhizy ◽  
C.P. Quichaud ◽  
A.P. Sagot ◽  
Pau P. France ◽  
M.P. Leturcq
Keyword(s):  
Mathematical Model ◽  
Full Scale ◽  
Full Scale Tests

scholarly journals MATHEMATICAL MODEL OF ANTILOCK BRAKING SYSTEM WITH INCLUSION OF THE QUATERNION

2020 ◽  
pp. 57-60
Author(s):  
E. A. Marchuk
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Kalman Filter ◽  
Braking System ◽  
Wheeled Vehicle ◽  
Antilock Braking System ◽  
Antilock Braking

The article discusses a description of rotation kinematics in representation of the quaternions and processing of vehicle onboard sensors signals having used Kalman Filter in relation to the task of mathematical modeling of antilock braking system of ground wheeled vehicle.

Drogues: A Study to Improve the Safety of Sailing Yachts

1988 ◽  
Vol 25 (02) ◽  
pp. 136-144
Author(s):  
Carol L. Hervey ◽  
Donald J. Jordan
Keyword(s):  
Mathematical Model ◽  
Full Scale ◽  
Breaking Wave ◽  
Potential Hazard ◽  
Regular Waves ◽  
Full Scale Tests ◽  
Large Improvement

Sailing yachts, in particular those less than 45 ft in length, face the potential hazard of breaking wave capsize when sailing offshore. A study was conducted using both model and full-scale tests to investigate the use of a drogue to alleviate the potential of capsize. In addition, a mathematical model was prepared which simulates the motion of a boat and drogue in regular waves and in a breaking wave strike. The results have shown that this technique offers the promise of a large improvement in safety, and it can be readily applied to the current fleet of sailing yachts with only minor modifications to existing hardware.

CALCULATION OF STAGES OF THE TECHNOLOGICAL PROCESS OF MANUFACTURE OF PPD DETECTORS USING COMPUTER MATHEMATICAL MODELING AND PRODUCTION OF ALPHA RADIOMETER ON THEIR BASIS

2020 ◽  
Vol 7 (2) ◽  
pp. 21-28
Author(s):  
SALI RADZHAPOV ◽  
◽  
RUSTAM RAKHIMOV ◽  
BEGJAN RADZHAPOV ◽  
MARS ZUFAROV
Keyword(s):  
Mathematical Modeling ◽  
Technological Process ◽  
Block Diagram ◽  
Large Diameter ◽  
Silicon Detector ◽  
Digital Processing ◽  
Main Element ◽  
Alpha Radiation ◽  
Initial Silicon ◽  
Natural Isotopes

The article describes the developed radiometer for Express measurement of alpha radiation of radioactive elements based on a large-diameter silicon detector. The main element of the PPD detector is made using computer mathematical modeling of all stages of the technological process of manufacturing detectors, taking into account at each stage the degree of influence of the properties of the initial silicon on the electrophysical and radiometric characteristics of the detector. Detectors are manufactured for certain types of devices. The developed radiometer is designed to measure alpha radiation of natural isotopes (238U, 234U, 232Th, 226Ra, 222Rn, 218Po, 214Bi, etc.) in various environments. It also shows the principle of operation of the device, provides a block diagram of the measuring complex, describes the electronic components of the radiometer, as well as the block diagram. Signal transformations (spectrum transfer, filtering, accumulation) are implemented programmatically on the basis of a digital processing module. The device can detect the presence of specific elements in various environments, as well as protect people from the harmful effects of adverse radiation and can be used both in the field and stationary.

Application of the method of mathematical modeling for forecasting channel deformations at the underwater crossing of the main pipeline

2020 ◽  
Vol 10 (6) ◽  
pp. 599-609
Author(s):  
Valery А. Gruzdev ◽  
◽  
Georgy V. Mosolov ◽  
Ekaterina A. Sabayda ◽  
◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Roughness Coefficient ◽  
Computational Domain ◽  
Channel Deformations ◽  
Geological Surveys ◽  
Kuban River ◽  
The Stability ◽  
Protective Structures

In order to determine the possibility of using the method of mathematical modeling for making long-term forecasts of channel deformations of trunk line underwater crossing (TLUC) through water obstacles, a methodology for performing and analyzing the results of mathematical modeling of channel deformations in the TLUC zone across the Kuban River is considered. Within the framework of the work, the following tasks were solved: 1) the format and composition of the initial data necessary for mathematical modeling were determined; 2) the procedure for assigning the boundaries of the computational domain of the model was considered, the computational domain was broken down into the computational grid, the zoning of the computational domain was performed by the value of the roughness coefficient; 3) the analysis of the results of modeling the water flow was carried out without taking the bottom deformations into account, as well as modeling the bottom deformations, the specifics of the verification and calibration calculations were determined to build a reliable mathematical model; 4) considered the possibility of using the method of mathematical modeling to check the stability of the bottom in the area of TLUC in the presence of man-made dumping or protective structure. It has been established that modeling the flow hydraulics and structure of currents, making short-term forecasts of local high-altitude reshaping of the bottom, determining the tendencies of erosion and accumulation of sediments upstream and downstream of protective structures are applicable for predicting channel deformations in the zone of the TLUC. In all these cases, it is mandatory to have materials from engineering-hydro-meteorological and engineering-geological surveys in an amount sufficient to compile a reliable mathematical model.

MATHEMATICAL MODEL OF RELIABILITY OF INFORMATION PROCESSING COMPUTER APPLIANCES FOR REAL-TIME CONTROL SYSTEMS

2020 ◽  
Vol 21 (3) ◽  
pp. 296-302
Author(s):  
A. V. Aab ◽  
◽  
P. V. Galushin ◽  
A. V. Popova ◽  
V. A. Terskov ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Information Processing ◽  
Control Systems ◽  
Real Time ◽  
Real Time Control ◽  
Time Control
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