The current paper is an overview on previous and ongoing research carried out by the authors concerning the use of Computational Fluid Dynamics for the accurate classification of hazardous Ex areas generated by flammable gases, for the optimization of computational simulation of air-methane mixture explosions by using ANSYS CFX and FLUENT and for calibrating computational simulations of gas explosions using the Schlieren effect. These research works containing analytic studies have led to the observation of basic principles which come to support the benefit of computational approaches for estimating gas dispersion within technological installations in which are handled or stored flammable materials and in which there are likely to occur explosive atmospheres. Preliminary results have led to the idea of developing a computational method for assessing the hazardous area extent in case of gas leak explosions in confined spaces. The computational method intended to be developed has to be validated in the lab using an experimental chamber as domain for analysing accidental flammable gas leaks from transportation installations and for studying the formation, ignition and burning of air-flammable gas mixtures in confined spaces. Results obtained from physical experiments will be used for calibrating the mathematical models. Further, verification and validation of computational simulations carried out based on physical experiments will be performed by a comparative analysis of virtual results with the experimental ones. In the end, the mathematical model will be implemented on a small-scale reproduction of a confined industrial area with explosion hazard.

Areas within which could arise explosive atmospheres having high concentrations, therefore requiring special precautions so as to guard the health and safety of concerned employees, are considered to be dangerous. If the electrical equipment used in these hazardous locations is not properly selected and installed for operating in explosive atmospheres, they are likely to generate an ignition and to result in explosion type events with significant environmental and material damages and, moreover, with human victims. Being an extremely difficult field to manage and having major importance, explosion prevention requires quality decisions. The reaching decision person must choose the best solution for putting into operation electrical apparatus in explosive atmospheres, taking into account certain factors, parameters, and the requirements for explosion protection and safety. Nowadays, special IT programs-decision support systems provide assistance for the reaching decision persons from a wide variety of domains. Explosion prevention shall not make an exception, especially because it firstly aims to improve the occupational health and safety of workers who operate within potentially explosive atmospheres. Taking into account the foregoing, the current paper presents the development and operation of a decision support system (DSS) for managing the selection and installation of explosion-proof electrical apparatus which are supposed to be used in atmospheres with explosion danger caused by burnable gases, liquids, vapours or mists.

This paper aims to study the behavior of air-gas explosion systems, in terms of propagation speed of pressure wave and flame front, based on experimental measurements in a shock tube, in order to prevent accidental pollution with the combustion gases. The characteristic parameters of the explosion process determined using the shock tube, the velocity of propagation of the flame front, the speed of propagation of the wave of pressure, explosion pressure at various distances from the source of initiation, can be used in the preparation of explosion risk assessment studies for technological processes carried out in potentially explosive atmospheres. Taking the developed technical measures would make possible ensure both the explosion protection and the prevention of accidental pollution with combustion gases.

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Most of the European countries have implemented large renewable energy systems that use wind energy, solar energy and water energy. In our country only water energy was used for many years. In the last period there is an obvious orientation towards the use of all types of renewable energy systems, which are both efficient and environmental friendly. The objective of our paper is to design an instrument for the evaluation of the best suited renewable energy system for different areas and type of use. Generally, the evaluation is made using some kind of expert system (ES) based on general rules. The novelty of our approach is the integration of the Quality Function Deployment (QFD) method in this evaluation process. The main advantage of the use of QFD method is that it offers a means to globally evaluate the best suited renewable energy system based on the specified requirements and the quality characteristics of the available systems. The QFD based expert system is validated by evaluating the best suited types of wind turbines for several different areas.