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The safety of small and medium LPG (liquefied petroleum gas) storage tanks in civil and industrial facilities w hen affected by forest fires in the framework o f Wildland-Urban Interface (WUI) was investigated. Large scale experimental tests were carried to characterize the behavior of LPG tanks in case of distant source radiation caused by forest fires. A data set was obtained and used for the validation of a dedicated two-dimensional computational fluid dynamic (2D CFD) model for the analysis of pressure build-up in vessels exposed to different types of transient heat radiation, featuring different geometry types and operating conditions. The combined experimental and numerical analysis allowed determining the critical exposure conditions for LPG vessels. Specific key performance indicators were defined and calculated on the basis of 2D CFD simulation results in order to derive conservative indications on failure conditions of LPG storage vessels induced by forest fires. [ABSTRACT FROM AUTHOR]

The presented experimental study was launched based on the LPG explosion accident near the city of Wenling, China, in June 2020. Multiple measurement methods have been coordinated in the experiments to capture different parameters. The damage size on the vessel is varied with replaceable rupture modules. The results show that the size of the damage is a decisive factor for distinguishing the outcome of the gas-releasing processes from a continuous discharging to a blowdown depressurization. The optical measurement illustrates the distributions of the released gas and indicates a much higher explosion potential of blowdown depressurization than continuous discharging. The experimental results confirm the rapid temperature drop due to the LPG-releasing, which has led to the embrittlement of the structure materials and was able to enlarge the damage size of the LPG tank. This new finding can largely increase the damage size on the tank and change the release process to blowdown depressurization. The damage escalation on the pressurized tank due to gas-release processes reveals the mechanism causing the disintegration of the tank as well as the severe explosion in the Wenling accident. According to the results, low alloy steel is not recommended for the structural material of LPG tanks. [Display omitted] • Experiment for simulating and investigating LPG depressurization in an accident. • Coordinated measurement methods for capturing the releasing gas flow behaviors. • Damage larger than 1.5‰ of the tank surface leads to high VCE potential of LPG. • Rapid temperature drops due to gas-releasing lead to embrittlement of the tank. • Revealing the depressurization-escalated damage of the tank in the real accident. [ABSTRACT FROM AUTHOR]

The temperature-coupled field analysis of liquefied petroleum gas (LPG) tank under fire is carried out based on wavelet finite element method. The wavelet finite element model is constructed through combing the heat conduct equation model and B-spline wavelet scale function. The temperature changing rules of LPG tank were obtained based on ANSYS software, wavelet finite element program, and test, respectively. The temperature changing rules of LPG and tank wall are obtained, and the effectiveness of the wavelet finite element method is verified. [ABSTRACT FROM AUTHOR]

Abstract: During wildland fires, homes located close to the fire can be threatened by the thermal heat flux from the firewall. Several studies have attempted to establish safety distances to protect people and prevent houses from burning, but no research has focused on the possible presence of an LPG tank, which would be supplying fuel for heating or cooking. This topic is, however, very important since hazards from a BLEVE (blast, fireball, fragments) can hurt firefighters during their intervention. This article aims to analyze the impact of a large crown fire on an LPG tank, if a mandatory safety zone of fifty meters is respected. Part One focuses on theoretical considerations aiming to (i) calculate the radiative heat fluxes impacting the tank, and (ii) perform a real scale test. Experiments were performed with a 2m3 LPG tank 15% full, with a heat flux from a natural gas burner system. The relevance of these test versus a real case is discussed. Results are in very good agreement with the expected heat fluxes, and suggest that there should be no BLEVE risk in the hypothetical conditions. [Copyright &y& Elsevier]

Abstract: A model has been developed to predict the thermal response of liquefied-pressure gases (LPG) tanks under fire, and three-dimensional numerical simulations were carried out on a horizontal LPG tank which was 60% filled. Comparison between numerical predictions and published experimental data shows close agreement. The attention is focused on the influence of different fire conditions (different fire scenarios, various engulfing degrees and flame temperatures) on thermal response of LPG tanks. Potential hazard probabilities under different fire conditions were discussed by analyzing the maximum wall temperature and media energy after the internal pressure rose to the same value. It is found that the less severe fire scenario and lower engulfing case may lead to a greater probability of burst hazard because of the higher maximum wall temperature and media energy before the pressure relief valve (PRV) opens. [Copyright &y& Elsevier]