TY - JOUR AU - Surikov, Андрей AU - Leshenyuk, Николай PY - 2018/08/17 Y2 - 2024/03/29 TI - Determination of simulation parameters values and output data interpretation in FDS during calculating visibility in smoke conditions JF - Journal of Civil Protection JA - JCP VL - 2 IS - 3 SE - Fire and industrial safety (technical sciences) DO - 10.33408/2519-237X.2018.2-3.308 UR - https://journals.ucp.by/index.php/jcp/article/view/135 SP - 308-319 AB - <p><em>Purpose.</em> The article is devoted to the development of methodological approaches to increasing the accuracy of visibility calculations for smoke in a room with the use of computational fluid dynamics model.</p><p><em>Methods.</em> Experimental and analytical justification of the values of smoke modeling parameters.</p><p><em>Findings.</em> The analysis of the method for determining the values of the calculated parameters used in the modeling of fires in the FDS software for calculating the dynamics of smoke in the room is analyzed. It is shown that the existing approaches to the determination of the values of the calculated parameters of smoke formation are valid only with complete combustion of materials under the conditions of standard tests for the smoke-forming ability. To take into account the incompleteness of combustion of materials, an analysis of the experimental data on the residue of the mass of materials, for which the smoke production coefficient was determined, was carried out.</p><p><em>Application field of research.</em> The results can be applied in modeling of fires.</p><p><em>Conclusions.</em> When determining the specific soot yield in the case of experimental data for a particular material, it is advisable to use the indicated values in the calculations, since they are usually higher than those determined according to the analytical method. The application of the analytical method is correct with complete combustion of the test sample. For a more correct determination of the soot yield, it is advisable to use coefficients that take into account the incomplete combustion of materials in determining the smoke production coefficients. Some values of the coefficients are given in this article. When simulating fires in FDS for the conversion of the smoke factor to the soot yield, it is advisable to apply the values of the smoke generation factor taking into account the test protocols for specific materials for the combustion regime. The data array obtained on the basis of the calculations of the value of the factor of visibility C for various materials and painted surfaces can be used to develop compensatory measures aimed at increasing the onset of critical values of the optical density of smoke in time when calculating the necessary evacuation time. When interpreting the output data for calculating the ultimate visibility under fire conditions using a computational fluid dynamics model, it is necessary to take into account the value of the integrated light extinction coefficient over the entire calculated optical transmission length. The adoption of local values of the coefficient is less correct.</p> ER -