Assessing Unconfined Vapor Cloud Explosions (Uvce) Physical Effects: A Software Built For Modelling With Bst Methodology

Year 2025, Volume: 13 Issue: 2, 512 - 525, 30.06.2025

Tahsin Aykan Kepekli

https://doi.org/10.29109/gujsc.1077377

Abstract

The calculation of physical effects of unconfined vapour cloud explosions (UVCE), which are caused by explosive atmosphere, is important for risk assessment studies. During the evaluation of explosive atmospheres, effects of a possible explosion are determined in order to take safety measures. There are various algorithms for calculating the overpressure. In physical effect calculations, evaluation of the surrounding environment and chemical reaction are important criteria for accuracy of the results. Usually, a large portion of risk assessment studies neglect overpressure damage assessment as these algorithms cannot be understood or implemented easily due to difficulties in usage. There are various software used in calculating explosion overpressure, however these software generally are run without assessing operating limits and scenario parameters correctly. Thereby, explosion effects cannot be evaluated properly in many explosive atmosphere risk assessments. Taking this as the basis for our aim, an overpressure calculation software called ExCALc has been coded for use in UVCE risk assessment studies. ExCALc uses Baker-Strehlow-Tang (BST) model. The parameters are input in a user friendly way and the scenario results are calculated for varying distances. It is thought that for complex methodology used in assessments, simplifying tools will benefit industrial safety in the long term.

Keywords

Fire and Explosion Analysis, Risk Assessment, Hazards Evaluation

Thanks

The author would like to acknowledge Dr. Tolga BARIŞIK (from Istanbul Yeni Yuzyil University Occupational Health & Safety Department) for his contribution on determining the validation method for the code calculation results.

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