Červený plamen - Laboratoř požárního inženýrství

Projects

Photogrammetric determination of wood char bulk density

Year: 2020
Participants: Šálek V., Jahoda M., Dupal O., Bakešová H.
Program: IGS University of Chemistry and Technology Prague
Annotation: The project deals with char bulk density of spruce wood and OSB board determination using photogrammetry. The aim is to build a photogrammetric apparatus, to determine the measurement error of the new photogrammetric apparatus, and to set requirements and limitations of measured samples (shape, size, gloss, geometrical irregularities of the sample surface, etc.). A methodology of sampling from chars created in controlled conditions of the cone calorimetry apparatus will be provided. The resulting values of bulk densities will be compared to literature and used in the specialized mathematical solver for the fire spread. The model results will be compared to experimental data.

Fire development modelling of engineered wood

Year: 2019-2022
Participants: Technical Institute of Fire Protection in Prague, Laboratory of Fire Engineering University of Chemistry and Technology Prague
Program: Safety research by the Ministry of the Interior of the Czech Republic
Annotation: Project deals with the problem of estimating the fire development model parameters to be used in CFD software. The scope of the project is to obtain a validated set of input parameters of thermal decomposition and burning behavior models for engineered wood. The ability to predict fire development and growth of such materials is of interest in the field of fire safe building design and fire investigation.

Performance of structures with timber fire protection – multi-physics modelling

Year: 2019-2021
Participants: Faculty of Civil Engineering Czech Technical University of Prague, Laboratory of Fire Engineering University of Chemistry and Technology Prague
Provider: Czech Science Foundation
Annotation: The project deals with modelling of structures fire protected by timber based materials which are environmental friendly and sustainable. The burned surface part of timber during fire becomes a layer of char, which insulates well the solid material below it. Due to the complexity of the behavior is the fire protection designed only on the basis of furnace tests without taken into account the actual fire. The project is designed to prepare a multi-physics model, which couples Computational Fluid Dynamics model with models of thermal degradation of timber, of heat transfer and development member and of mechanical behaviour of the member. The proposed hierarchy of calibration and validation on experiments ensures the required accuracy of the solution and the applicability of simulations for different materials. A description of the significant interaction of phenomena allows to predict the behaviour of structures using accurate models of real fires.

Accidental release of CNG from passenger vehicles

Year: 2017-2019
Participants: Technical Institute of Fire Protection in Prague, Laboratory of Fire Engineering University of Chemistry and Technology Prague
Program: Safety research by the Ministry of the Interior of the Czech Republic
Annotation: The aim of the project is to study the accidental release of CNG from the pressure vessels in the passenger cars, its dispersion from the source and combustion in the enclosure. The release of the CNG from the pressure vessel through the safety valve is first studied experimentally. Output of the experimental study is used as an input to the Computational Fluid Dynamics model. CFD is used to predict the dispersion of the gas from the release source and its combustion in enclosures.

Study of emergency methane release from passenger car pressure vessel

Year: 2015
Participants: Ira J., Jahoda M., Roučková E., Topinková K., Kubečková N. S.
Program: IGS University of Chemistry and Technology Prague
Annotation: The project studies the release of compressed natural gas (CNG) from passenger car pressure vessels. CNG represents one of the main alternatives to classic liquid fuels (petrol, diesel) at the moment. Even though, CNG is cheaper and more environmentally friendly car fuel alternative, highly questionable safety of CNG fuel systems slows down its mass application. The main aim of the project is to describe in detail CNG systems behavior in fire conditions using a large scale fire test. Various temperature loads in different pressure vessel locations are simulated using CFD method and the temperature response of the safety valve is tested. 

Modeling of transport and kinetic processes during thermal decomposition of solid materials

Yeat: 2014
Participants: Ira J., Hasalová L., Jahoda M., Vaněk P.
Program: IGS University of Chemistry and Technology Prague
Annotation: The project deals with mathematical modeling of solid material thermal decomposition during fire and its application in CFD solvers. The main aim is to find a suitable methodology for obtaining kinetic input parameters via mathematical optimization using Shuffled Complex Evolution (SCE) algorithm. The numerical stability of algorithm and initial conditions effect on results will be tested both on synthetic data and previously obtained experimental data. As a part of the project, the extension of already existing SCE code by parallel and subsequent reactions is planned. Subsequently, the transferability of the obtained model parameters into CFD solvers Fire Dynamics Simulator a FireFOAM, where the heat conduction and radiation are added, will be solved. The CFD simulations results will be validated using experimental cone calorimetry data.  

 

Mathematical models of fire spread input parameters identification and verification

Year: 2013
Participants: Hasalová L., Ira J., Jahoda M., Kálal Z.
Program: IGS University of Chemistry and Technology Prague
Annotation: The project deals with the validation of mathematical models describing the thermal degradation of solid materials and the speed of volatile liquids evaporation during fire. The models play a key role in the numerical prediction of fire spread. The project comprises experimental determination of liquids mass loss during fire, flame geometry and temperatures, and container surface temperature. The model input parameters are computed from previously obtained experimental measurements using mathematical optimization methods. A genetic algorithm or Shuffled Complex Evolution algorithm is used. A transferability of obtained model input parameters into Fire Dynamics Simulator and suitability of ANSYS Fluent solver for liquids burning simulations are further tested.

Study of experimental data evaluation methods for obtaining input parameters of solid material thermal decomposition and burning mathematical models

Year: 2012
Participants: Hasalová L., Ira J., Jahoda M.
Program: IGS University of Chemistry and Technology Prague
Annotation: The project deal with the methodology of experimental data evaluation (especially evolutionary optimization algorithms) obtained from materials thermal decomposition measurements and material behavior during fire. The experimental data include in particular thermogravimetric analysis and cone calorimetry measurements. The data provide information about the thermal response and decomposition kinetics of solid materials, however, they are not directly applicable to mathematical models describing the thermal degradation and burning of solids. It is, therefore, necessary to develop a general methodology of experimental data evaluation, which would enable to create a specialized database of material properties to be used in fire models. The database would fill a gap between theoretical model options and their application in practical use.