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The reaction dynamics of combustible clouds at high temperatures and pressures are a common form of energy output in aerospace and explosion accidents. The cloud explosion process is often affected by the external initial conditions. This study aims to numerically study the effects of airflow velocity, initial temperature and fuel concentration on the explosion behavior of isopropyl nitrate/air mixture in a semiconstrained combustor.

The discrete-phase model was adopted to consider the interaction between the gas-phase and droplet particles. A wave model was applied to the droplet breakup. A finite rate/eddy dissipation model was used to simulate the explosion process of the fuel cloud.

The peak pressure and temperature growth rate both decrease with the increasing initial temperature (1,000–2,200 K) of the combustor at a lower airflow velocity. The peak pressure increases with the increase of airflow velocity (50–100 m/s), whereas the peak temperature is not sensitive to the initial high temperature. The peak pressure of the two-phase explosion decreases with concentration (200–1,500 g/m³), whereas the peak temperature first increases and then decreases as the concentration increases.

Chain explosion reactions often occur under high-temperature, high-pressure and turbulent conditions. This study aims to provide prevention and data support for a gas–liquid two-phase explosion.

Sustained turbulence is realized by continuously injecting air and liquid fuel into a semiconfined high-temperature and high-pressure combustor to obtain the reaction dynamic parameters of a two-phase explosion.

This paper aims to provide graduate students, researchers, governmental and independent agencies with an overview on static electricity.

Static electricity has been studied by researchers, academicians, company specialists, governmental and independent agencies. Static electricity incidents have been collected from several sources such as the technical, general articles, internet web sites, and internal reports. The static electricity definition, incidents, hazards, and static electricity prevention have been reviewed. The static electricity incidents have been arranged and classified into fire, and explosions.

Static electricity can be the cause of problems in many areas of industry. It presents a source of ignition for flammable gases, liquids and powders. It can cause fires and explosions in tankers, aircraft and petrochemical plant and in printing, pharmaceutical, food products and explosives industries.

This paper presents an overview on static electricity, the incidents, and the methods to prevent static electricity generation and accumulation.

This paper aims to provide graduate students, researchers, flare design and operational oil companies with an overview on the flare incidents.

The design and operation of flares have been the subject of research and concern to the academicians and to flare design and operational oil companies. The flare incidents have been collected from several sources such as the technical, general articles, internet web sites, and internal reports. The flare incident types and causes have been reviewed. This paper presents an overview on the flare incidents. The paper presents a flare incident at an oilfield. The paper summarizes the causes and the results of the incident.

A lesson was learned that a flashback scenario could occur at the high‐pressure flares unless the flare system was designed properly. A flare system should be designed according to the standard codes. American Petroleum Institute API 521 recommended guidelines on the design of the relief system. John Zinc Company and GKN also recommended guidelines for the installation and protection of flares.

This paper presents the flare incident types and causes. The paper also presents an overview on a flare incident at an oilfield. The paper summarizes the causes and the results of the incident. This information can be beneficial in order to prevent similar flare incidents.

The purpose of this paper is to analyze the reliability of the quantitative risk model used for planning inspection and maintenance activities. The objective is to critically discuss the factors that contribute to the probability and consequence of failure calculations.

The case study conducted using one of the most widely deployed risk models in the oil and gas industry where a full assessment was performed on an offshore gas producing platform.

The generic failure frequencies used as the basis for calculating the probability of failure are set at a value representative of the refining and petrochemical industry's failure data. This failure database does not cover offshore. The critical discussion indicated the lack of basis of the coefficient of variances, prior probabilities and conditional probabilities. Moreover, the risk model does not address the distribution of thickness measurements, corrosion rates and inspection effectiveness, whereas only overall deterministic values are used; this requires judgment to determine these values. Probabilities of ignition, probabilities of delayed ignition and other probabilities in Level 1 event tree are found selected based on expert judgment for each of the reference fluids and release types (i.e. continuous or instantaneous). These probabilities are constant and independent of the release rate or mass and lack of constructed model. Defining the release type is critical in the consequence of the failure methodology, whereas the calculated consequences differ greatly depending on the type of release, i.e. continuous or instantaneous. The assessment results show that both criteria of defining the type of release, i.e. continuous or instantaneous, do not affect the calculations of flammable consequences when the auto-ignition likely is zero at the storage temperature. While, the difference in the resulted toxic consequence was more than 31 times between the two criteria of defining the type of release.

There is a need to revamp this quantitative risk model to minimize the subjectivity in the risk calculation and to address the unique design features of offshore platforms.

This case study critically discuss the risk model being widely applied in the O&G industry and demonstrates to the end-users the subjectivity in the risk results. Hence, be vigilant when establishing the risk tolerance/target for the purpose of inspection and maintenance planning.

This paper aims to provide graduate students, researchers, governmental and independent agencies with an overview on the stages and management of technological disasters.

The technological disasters are a subject of concern to the researchers, the academicians, the governmental and independent agencies. The disasters, which involve major hazard installations (MHIs), are known as technological disasters. The information has been collected from several sources such as the technical, and general articles, internet web sites, and internal reports. The technological disaster definition and stages have been reviewed. This paper presents an overview on the technological disaster management cycle.

Technological disasters consist of three stages. The stages are classified into pre‐, during and post‐disaster stages. Disaster management is a collective term encompassing all aspects of planning for and responding to disasters, including both pre‐disaster and post‐disaster activities. Disaster management cycle is an open‐ended process. The four phases comprising the cycle begin and end with mitigation. The stages are not mutually exclusive – there is an overlap. The stages of disaster management can be operative concurrently, because those stages are interrelated; they are not independent entities with one stopping and the next following.

This paper presents an overview on the technological disaster definition and stages. It provides the MHIs management and the related authority with a background on the technological disaster management cycle. It motivates the members of the MHIs, particularly managerial staff, and the emergency planners to continually improve the control of MHIs. It provides the background and basis for further research in disaster and disaster management.

It is known that there are hazards associated with the storage, handling and use of liquefied petroleum gas. Storage process plants of dangerous substances define the set of risk sources. Release of chemical due to accident could be severe and poses an immediate effect to workers on‐site and communities off‐site as well as it causes adversely a potential effect on the environment. LPG is considered to be a very important fuel and chemical feed stock. The material has been involved in many major fires and explosions. This paper presents the most recent analysis techniques for evaluating several physical models. These models are used to calculate the physical effects of explosion and fire from LPG accidents and also to predict the affected area.

The purpose of this work is to present the implementation of weighted essentially non-oscillatory (WENO) wavelet methods for solving multiphase flow problems. The particular interest is gas–liquid two-phase mixture with velocity non-equilibrium. Numerical simulations are carried out on different scenarios of one-dimensional Riemann problems for gas–liquid flows. Results are validated and qualitatively compared with solutions provided by other standard numerical methods.

This paper extends the framework of WENO wavelet adaptive method to a fully hyperbolic two-phase flow model in a conservative form. The grid adaptivity in each time step is provided by the application of a thresholded interpolating wavelet transform. This facilitates the construction of a small yet effective sparse point representation of the solution. The method of Lax–Friedrich flux splitting is used to resolve the spatial operator in which the flux derivatives are approximated by the WENO scheme.

Hyperbolic models of two-phase flow in conservative form are efficiently solved, as shocks and rarefaction waves are precisely captured by the chosen methodology. Substantial computational gains are obtained through the grid reduction feature while maintaining the quality of the solutions. The results indicate that WENO wavelet methods are robust and sufficient to accurately simulate gas–liquid mixtures.

Resolution of two-phase flows is rarely studied using WENO wavelet methods. It is the first time such a study on the relative velocity is reported in two-phase flows using such methods.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

FIRE control has two phases; prevention and cure. Of these the first is obviously the most important, but serious attention must none the less be given to the second.

Gas evolution within lithium-ion batteries (LIBs) gives rise to safety concerns that question their applicability. The gas evolution is not only the result but also the inducement of performance deterioration of LIBs. In this paper, the growth characteristics and dynamic behavior of gas bubble on the electrode surface are studied, and the interference mechanism of gas evolution on Li-ion diffusion or Li-ion conduction within LIBs is discussed and validated by the numerical simulations.

First, the mathematical models and simulation method are established. The growth and flow of gas bubble in the serpentine channel on electrode surface, which results from the gas-liquid flow and the effects of surface tension, is modeled by using the multi-phase Navier-Stokes and the volume of fluid method. Integrating Butler–Volmer and Fick’s law, the mathematical model of ions transport in the electrochemical cell is set-up. Second, the motion of gas bubble is tracked, and the variations of bubble shape and characteristic parameters with time are obtained by the computed fluid dynamics (CFD) method.

Based on the CFD results, the battery models and electrochemical simulations are carried out to analyze the ionic transport characteristics. The results show that the microstructural morphology such as the serpentine channel shape and size on electrode surface are important aspects for the gas bubble growth and the local ionic transport. Li ions significantly accumulate at one side of the gas obstacle, hindering the ionic diffusion normally. When the gas bubble blocks the electrolyte, the passage of ions from the positive to the negative is interrupted, and the open circuit zone of the electrochemical cell is formed.

The gas evolution within LIBs is not only a result but also an inducement of its performance deterioration. The primary issues in this study are the growth characteristics and dynamic behavior of gas bubble on the electrode surface, providing the knowledge for the interference mechanism of gas evolution on ionic transport and ultimately leads to significant increase of battery resistance.