{"id":3320,"date":"2026-04-09T14:40:08","date_gmt":"2026-04-09T12:40:08","guid":{"rendered":"https:\/\/silentdynamics.de\/?p=3320"},"modified":"2026-05-09T23:28:03","modified_gmt":"2026-05-09T21:28:03","slug":"ausbreitung-von-gasen-in-der-umwelt","status":"publish","type":"post","link":"https:\/\/silentdynamics.de\/en\/2026\/04\/09\/ausbreitung-von-gasen-in-der-umwelt\/","title":{"rendered":"Dispersion of gases in the environment"},"content":{"rendered":"<h2 class=\"wp-block-heading\">CFD simulation of gas dispersion in accident scenarios \u2013 Safety analysis for light and heavy gases<\/h2>\n\n\n\n<p>For industrial plants, chemical facilities, energy supply infrastructures, and safety-critical installations, the uncontrolled release of gases in the event of a malfunction poses a significant risk to people, the environment, and assets. The precise prediction of gas dispersion is therefore an essential component of modern safety analyses, risk assessments, and emergency planning.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Simulation-based Accident Analysis with CFD<\/h2>\n\n\n\n<p>Using CFD (Computational Fluid Dynamics) simulations, escaping gases in fault scenarios \u2013 both light gases (e.g., hydrogen, methane, ammonia) and heavy gases (e.g., chlorine, propane, CO\u2082) \u2013 are precisely captured in their spatial and temporal dispersion. The simulation takes into account the immediate surroundings (building contours, obstacles, terrain structure) as well as the distant surroundings (building density, topography, open areas) to model realistic dispersion scenarios.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Stationary and transient concentration fields<\/h2>\n\n\n\n<p>The calculation of both steady-state and transient concentration fields allows for a differentiated assessment of the dispersion dynamics:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Stationary fields<\/strong> show the steady state under a constant leakage rate and provide information about permanently critical zones, explosion limits (LEL\/UEL), and toxicity thresholds (e.g., ERPG, AEGL, or IDLH values).<\/li>\n\n\n\n<li><strong>Transient fields<\/strong> depict the temporal course of the spread \u2013 from release through cloud formation to dilution \u2013 and are crucial for assessing evacuation periods and alarm concepts.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Influence of different wind directions and meteorological conditions<\/h2>\n\n\n\n<p>Wind direction, wind speed, and atmospheric stability classes (according to Pasquill-Gifford or Monin-Obukhov) have a significant influence on the range, concentration, and hazard zone of a gas cloud. By systematically varying these parameters, all safety-relevant scenarios are covered \u2013 from calm weather conditions with low mixing to turbulent flow with rapid dilution.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Transient Inflow Boundary Conditions in Atmospheric Boundary Layers<\/h2>\n\n\n\n<p>An essential quality feature of the simulation is the use of custom-developed transient inflow boundary conditions for atmospheric boundary layers. In contrast to simplified wind profiles, realistic, time-varying flow profiles with turbulent boundary layer structure are used. This ensures a high degree of agreement with real meteorological conditions and significantly increases the reliability and validity of the simulation results \u2013 a crucial advantage over classic Gaussian dispersion models.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Application areas and regulatory framework<\/h2>\n\n\n\n<p>CFD-based gas dispersion simulation is used in:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Accident Prevention Ordinance (12. BImSchV) \/ Seveso III Directive:<\/strong> Proof of safe distances and safety zones<\/li>\n\n\n\n<li><strong>Safety reports and QRA (Quantitative Risk Assessment):<\/strong> Basis for probabilistic risk assessments<\/li>\n\n\n\n<li><strong>Fire and disaster control planning:<\/strong> Support for deployment scenarios and evacuation planning<\/li>\n\n\n\n<li><strong>Facility Planning and Approval Procedures<\/strong> Early identification of critical spread pathways<\/li>\n<\/ul>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>","protected":false},"excerpt":{"rendered":"<p>CFD-Simulation von Gasausbreitung im St\u00f6rfall \u2013 Sicherheitsanalyse f\u00fcr leichte und schwere Gase Bei industriellen Anlagen, Chemiebetrieben, Energieversorgungsinfrastrukturen und sicherheitsrelevanten Einrichtungen stellt die unkontrollierte Freisetzung von Gasen im St\u00f6rfall ein erhebliches Risiko f\u00fcr Mensch, Umwelt und Sachwerte dar. Die pr\u00e4zise Vorhersage der Gasausbreitung ist daher ein wesentlicher Bestandteil moderner Sicherheitsanalysen, Risikobeurteilungen und Notfallplanungen. Simulationsbasierte St\u00f6rfallanalyse mit [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1453,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[968],"tags":[],"class_list":["post-3320","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-thermodynamik"],"_links":{"self":[{"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/posts\/3320","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/comments?post=3320"}],"version-history":[{"count":3,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/posts\/3320\/revisions"}],"predecessor-version":[{"id":3392,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/posts\/3320\/revisions\/3392"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/media\/1453"}],"wp:attachment":[{"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/media?parent=3320"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/categories?post=3320"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/silentdynamics.de\/en\/wp-json\/wp\/v2\/tags?post=3320"}],"curies":[{"name":"WordPress","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}