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

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.

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

Izvestiya MGTU MAMI ◽

10.31992/2074-0530-2020-46-4-46-60 ◽

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.

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Experience in conducting field tests of metal structural constructions of coatings of the “BrSTU”

E3S Web of Conferences ◽

10.1051/e3sconf/202021202015 ◽

2020 ◽

Vol 212 ◽

pp. 02015

Author(s):

Mikalai Shalabyta ◽

Andrei Shuryn ◽

Tatsiana Shalabyta ◽

Viacheslav Dragan

Keyword(s):

Theoretical Calculations ◽

Field Tests ◽

Full Scale ◽

Complex Structures ◽

Building Structures ◽

The World ◽

Special Approach ◽

Full Scale Tests ◽

Degree Of Participation ◽

First Time

There are quite often statically complex structures, the reliability of theoretical calculations of which needs experimental verification in the world practice of design and construction. Studies of building structures functioning can be full-scale or carried out on their models in laboratory conditions depending on the goals set. Full-scale tests of building structures are more expensive, therefore, their implementation requires a special approach and justification. However, to check the operation of complex, critical structures which primarily include metal spatial large-span structures of coatings of buildings and structures especially those used for the first time to assess their bearing capacity, to establish the degree of participation in the construction of each of the elements, to study the operation of individual new nodal elements etc., only full-scale tests are required.

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Advances in the Railroad Locomotive Crashworthiness

Transportation: Making Tracks for Tomorrow’s Transportation ◽

10.1115/imece2003-55233 ◽

2003 ◽

Author(s):

Swamidas Punwani ◽

Gopal Samavedam ◽

Steve Kokkins

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Impact Strength ◽

Full Scale ◽

Fuel Tank ◽

Structural Components ◽

Dynamic Impact ◽

Element Analysis ◽

Simulation Results ◽

Full Scale Tests

The paper describes locomotive and fuel tank crashworthiness research being conducted by the Federal Railroad Administration for improved safety of the locomotive crew under collision scenarios. The research involves static and dynamic impact strength evaluations of locomotive structural components. These evaluations which are based on full scale tests and simulations using finite element analysis are described in this paper. Correlations between the test and simulation results are also presented in some cases.

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Числове та експериментальне дослідження наповнення резервуару компонентом газової суміші

Aerospace technic and technology ◽

10.32620/aktt.2021.4.09 ◽

2021 ◽

pp. 63-72

Author(s):

Ольга Володимирівна Шипуль ◽

Сергій Олександрович Заклінський ◽

Володимир Вікторович Комбаров ◽

Олексій Анатолійович Павленко ◽

Вадим Олегович Гарін

Keyword(s):

Mathematical Models ◽

Numerical Models ◽

Control Point ◽

Calculated Data ◽

Full Scale ◽

Mixture Component ◽

Gas Mixture ◽

Gas Temperature ◽

Gas Dynamic ◽

Simulation Results

The subject of the research is mathematical models of a gas-dynamic non-stationary process of filling a vessel with a component of a gas mixture. The aim of the study is the scientific and experimental substantiation of the choice of a model of filling a vessel with a component of a gas mixture with a given accuracy. The objectives of the study are to conduct full-scale experiments on filling the vessel with gas for further verification of the gas mixture generation control system, as well as in the development of adequate mathematical models of gas-dynamic flow, the analysis of simulation results, and the use of verified results in the system of automated generation of a gas mixture of a given accuracy by assessing the mass of its components depending on the filling parameters. The tasks are solved by studying the results of numerical modeling of the process and full-scale experiments. The following results are obtained. A series of full-scale experiments on filling a vessel with high-frequency monitoring of the pressure and temperature of the gas being filled was carried out. Significant factors were analyzed. The use of SAS SST turbulence models was substantiated. Models of the gas-dynamic unsteady process of filling the vessel with a component of the gas mixture for various values of the mass flow rate had been built. All the simulations were carried out using the ANSYS CFX software package. The influence of considering a heat exchange with the vessel walls on the studied parameters of the mixture is determined, namely: pressure, gas temperature averaged over the volume, gas temperature in a control point, mass of the component of a gas mixture. It was found that the deviation of the calculated data when using a model with an adiabatic condition on the wall compared to a model with a constant temperature regime is: for pressure – no more than 5 %, for averaged temperature – 6 %, for the temperature at the monitor point – 9 %, for mass – 1.5 %. The discrepancy between the simulation results and the full-scale experiment does not exceed 12 % in pressure and temperature at the monitor point, as well as 4 % in the mass of the component. By the experimentally determined accuracy parameter of the gas mixture (the mass of the mixture component in particular), the numerical models had been corrected to provide the mass value error of no more than 0.5 %.

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Modeling fires in structures with an atrium in the FDS field model

MATEC Web of Conferences ◽

10.1051/matecconf/201819303023 ◽

2018 ◽

Vol 193 ◽

pp. 03023 ◽

Cited By ~ 6

Author(s):

Oleg Nedryshkin ◽

Marina Gravit ◽

Kirill Grabovyy

Keyword(s):

Experimental Data ◽

Comparative Analysis ◽

Fire Safety ◽

Safety Assessment ◽

Field Model ◽

Calculated Data ◽

Full Scale ◽

Software System ◽

Fire Model ◽

Full Scale Tests

Modeling of dangerous fire factors is an important element in the system of modern fire safety assessment of buildings and structures. The paper presents a comparative analysis of the characteristics of the software system PyroSim. The verification of the fire model in the FDS program, which was performed on the basis of full-scale tests conducted by Professor Chau W.L., was analysed. The analysis of empirical and calculated data on modeling of fire in the atrium is made. The conclusion is made about the accuracy of simulation in the FDS program and the coincidence of the experimental data with the calculated ones.

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Seismic performance of a full-scale, reinforced high-performance concrete building. Part I: Experimental study

Canadian Journal of Civil Engineering ◽

10.1139/l08-017 ◽

2008 ◽

Vol 35 (8) ◽

pp. 832-848 ◽

Cited By ~ 8

Author(s):

Sébastien Mousseau ◽

Patrick Paultre

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Dynamic Testing ◽

Dynamic Properties ◽

Full Scale ◽

Building Structures ◽

Seismic Behaviour ◽

Earthquake Excitation ◽

Concrete Building ◽

Full Scale Tests

Full-scale tests provide valuable information on the characteristics of building structures that can be used to evaluate design methods, to calibrate modelling techniques, and to determine damage corresponding to loading levels. These tests are scarce due to the enormous requirements in testing space and specialized testing equipment. The seismic behaviour of a full-scale, two-storey, reinforced high-performance concrete building designed with moderate ductility detailing is evaluated by pseudo-dynamic testing, during which increasing seismic loads are applied, resulting in increasing levels of permanent damage to the structure. To monitor the level of damage, a series of successive forced-vibration tests are also carried out at each step of the process and are used to track changes in the key dynamic properties of the building. The paper presents the design of the test structure according to the new edition of the CSA A23.3-04 Design of concrete structures standard, the series of pseudo-dynamic tests simulating different levels of earthquake excitation consistent with the 2005 edition of the National building code of Canada, and the evaluation of the performance of the building. It is shown that the detailing requirements of CSA A23.3-04 are more than adequate to provide the ductility and overstrength expected.

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Investigation the effect of outdoor air infiltration on the heat-shielding characteristics the outer walls of high-rise buildings

E3S Web of Conferences ◽

10.1051/e3sconf/20183302006 ◽

2018 ◽

Vol 33 ◽

pp. 02006

Author(s):

Yu.S. Vytchikov ◽

A. B. Kostuganov ◽

M. E. Saparev ◽

I. G. Belyakov

Keyword(s):

Heat Transfer ◽

Calculated Data ◽

Outer Wall ◽

Full Scale ◽

Outdoor Air ◽

Public Buildings ◽

High Rise ◽

Air Infiltration ◽

Heat Shielding ◽

Story Building

The presented article considers the influence of infiltrated outdoor air on the heat-shielding characteristics of the exterior walls of modern residential and public buildings. A review of the sources devoted to this problem confirmed its relevance at the present time, especially for high-rise buildings. The authors of the article analyzed the effect of longitudinal and transverse air infiltration on the heat-shielding characteristics of the outer wall of a 25-story building that was built in Samara. The results showed a significant reduction of the reduced resistance to the heat transfer of the outer wall when air is infiltrated through it. There are the results of full-scale examination of external walls to confirm the calculated data. Based on the results of the study carried out by the authors of the article, general recommendations on the internal finishing of the outer walls of high-rise buildings are given.

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Structural Means for Fire-Safe Wooden Façade Design

Fire Technology ◽

10.1007/s10694-021-01174-2 ◽

2021 ◽

Author(s):

Thomas Engel ◽

Norman Werther

Keyword(s):

Thermal Expansion ◽

Full Scale ◽

Fire Tests ◽

External Wall ◽

Joint Design ◽

The Future ◽

Construction Type ◽

Full Scale Tests ◽

Fire Stops

AbstractThis study investigates five fire stop variants used to limit the spread of fire on wooden façades. For this purpose, five fire tests using various types of wooden façade claddings and different fire stops were conducted as full-scale tests and compared to the existing findings. The influences and interactions between the material qualities of the external wall behind the façade cladding, the construction type of the wooden façade cladding, the design of the substructure, the depth of the ventilation gap, and the design of the fire stops were investigated. In evaluating the fire stops, the design of the interior corners, the joint design, and the influence of thermal expansion were examined. Finally, design proposals for the design of fire stops at wooden façades in order to limit the spread of fire were derived based on this evaluation. The outlook presents further needs that need to be investigated in the future in order to clarify undiscussed aspects or points that were ultimately not evaluated within the scope of this study. Graphical Abstract

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