Agency: Cordis | Branch: FP7 | Program: MC-IRSES | Phase: FP7-PEOPLE-2012-IRSES | Award Amount: 830.30K | Year: 2012
Pipeline systems have supreme significance for an effective functioning of industry providing Eastern and Western European markets with energy resources: crude oil, natural gas and liquid petroleum products. Taking into account long life of pipeline networks and situation, when over 20% of large-diameter pipelines are with an exhausted lifetime, an important task at the present time becomes an ensuring of reliability for these transport systems. An intensive study shows that among the main reasons of pipeline accidents are the volumetric surface defects (VSD) arising as a result of corrosion or erosion-corrosion processes and by this way considerably decreasing the pipeline strength. In order to ensure efficient and safe operation of existing pipelines, operating companies routinely inspect the pipes. The methods that are used for this purpose, like smart pig, are sufficiently expensive, require, in some cases, significant reconstruction and have an insufficient sensitivity. An application of new composite materials for the repair of damaged pipelines considerably improved situation in the last time. However numerous standards associated with this type of repair are based on simplified approaches and do not take into account the stress-strain state in the damaged areas. Strategic objective of the project is addressed to the improvement of infrastructure in EU and Third counties by the rising of reliability of existing pipeline systems. Work over this project will serve IRSES main goal achievement strengthening research partnerships through short period staff exchanges and networking activities between organisations from EU and Third countries. The scientific and technical objectives are improvement of existing and developing of new methods for detection and repair of VSD based on low-frequency ultrasonic testing with directional waves and advanced composite repair systems to bring efficiency of damaged section up to the level of undamaged pipeline.
Cleja-Tigoiu S.,University of Bucharest |
Iancu L.,Petroleum Gas University of Ploiesti
International Journal of Plasticity | Year: 2013
This paper is devoted to elasto-plastic orthotropic model within the multiplicative elasto-plasticity, which describes the change of the orthotropic axes, i.e., orientational anisotropy and the strength-differential effect, when the yield condition is pressure insensitive and dependent on the third invariant of the stress. The orthotropy directions are characterized by Euler angles within the constitutive framework with small elastic strains, large elastic rotations and large plastic distortions. The presence of the plastic spin makes possible the description of the orientational anisotropy. We make herein an attempt to develop a hardening model, which includes the kinematic hardening given by Armstrong and Frederick (1966) law adapted to orthotropic material and isotropic hardening, and complies with the experimentally observed plastic yield and flow behaviour reported by Verma et al. (2011) in tension-compression- tension and compression-tension-compression. By pushing away to the actual configuration the material response, the rate form of the model with the objective derivatives expressed via the elastic rotations is characterized by a differential system for the following unknowns: the Cauchy stress, plastic part of deformation, tensorial and scalar hardening variables and Euler angles. We present the rate elasto-plastic model with a plastic spin in the case of an in-plane rotation of the orthotropy direction, and a plane stress, respectively. In the plane stress, the equation for the rate of the strain in the normal direction is first derived and subsequently the modified expression for the plastic multiplier associated with an in-plane rate of the deformation becomes available. Numerical simulations for the homogeneous deformation process on the sheets and comparisons with experimental data make possible a selection among the plastic spins introduced in this paper, aiming at obtaining a good agreement with the experiments performed for an in-plane stress state by Kim and Yin (1997). When the shear deformation of the plate is numerically simulated, the stabilization of the orientational anisotropy occurs in the presence of the plastic spin, in contrast with the unreasonable behaviour produced in the absence of the plastic spin. © 2013 Elsevier Ltd. All rights reserved.
Schwartz W.R.,Yale University |
Ciuparu D.,Petroleum Gas University of Ploiesti |
Pfefferle L.D.,Yale University
Journal of Physical Chemistry C | Year: 2012
Palladium-based catalysts supported on metal oxides are attractive for methane combustion at low temperature. However, at temperatures below 450 °C, their tendency to deactivate hinders their usefulness. Catalytic deactivation in this temperature regime has been attributed to a water/hydroxyl inhibition effect. We investigated this effect to better understand the mechanism for catalytic deactivation. Comparative in situ FTIR transmission spectroscopy experiments at 325 °C revealed that hydroxyl accumulation occurs on the oxide supports during catalytic methane combustion and deactivation. The water/hydroxyl accumulation on the support is slow to desorb at this temperature. In light of our recent finding that oxygen from the support is utilized in the methane combustion process, we propose that hydroxyl/water accumulation on the support impedes the catalytic combustion reaction by hindering oxygen mobility on the support. We support this hypothesis by demonstrating that the presence of water on the catalyst inhibits oxygen exchange with the oxide support. © 2012 American Chemical Society.
Toader F.A.,Petroleum Gas University of Ploiesti
Studies in Informatics and Control | Year: 2015
The Job Shop Scheduling Problem (JSSP) is regarded as one of the most challenging issues by the research community in this field due to its complexity. This paper presents a hybrid algorithm called H-PSO-SA for JSSP which is a mixture of two computational artificial intelligence algorithms: Particle Swarm Optimization and Simulated Annealing. In order to demonstrate efficiency of the proposed hybrid algorithm, a series of tests are conducted using a set of classical JSSP benchmarks. The schedule results are compared with outcomes well known in the scientific literature. © ICI Bucharest 2010-2015.
Popa C.,Petroleum Gas University of Ploiesti
Revista de Chimie | Year: 2013
In the second part of the paper is presented the hierarchical control structure, which is organized on three levels: conventional control level, advanced control level, and optimal control level; each levels being characterized by the output - input values and by dynamic characteristics. The author gives special attention to the second level, where was developed based on a model predictive controller. The investigation of performances for the predictive controller was performed using the dynamic simulator presented in the first part of the paper. From economic point of view, the development and the implementation of the hierarchical control structure for the catalytic cracking process is leading to increase the overall plant efficiency.
Radulescu G.,Petroleum Gas University of Ploiesti
Revista de Chimie | Year: 2016
A crude oil plant is a classic unit, having one main column, several sidestrippers and pumparounds. Although its steady state modeling and simulation is a well "known-and-solved" problem, only too little is known about the dynamic simulation of such a plant intimacy. The models for that exist, but the open references mention serious difficulties in building-up a dynamic model that could be appropriate for numerical integration. On the other hand, closed commercial tools for crude oil unit study are developed every day, but they limit the user to the models, parameters and state variables that the producing company is willing to provide its clients. Following a series of two other papers [1, 2], which present in detail the problem of a crude oil plant modeling and dynamic simulation, this work makes a step ahead. An open-loop unit detailed response is given and analyzed, and also interesting features (like unit inverse response) are obser ved here, denoting a good agreement with plant experimental data.
Fendu E.M.,Petroleum Gas University of Ploiesti |
Oprea F.,Petroleum Gas University of Ploiesti
Journal of Chemical and Engineering Data | Year: 2013
The properties of 2-(2-[2-(2-hydroxypropoxy)propoxy]propoxy)propan-1-ol (tetrapropylene glycol, TePG) were measured as a function of temperature: vapor pressure (409.85 to 582.15) K, density (298.15 to 443.15) K, viscosity (288.15 to 393.15) K, and surface tension (298.15 to 468.15) K. The obtained data for tetrapropylene glycol were regressed using correlations from simulation software. We are developing a new industrial process to separate propylene glycols mixtures, obtained via the hydrolysis of 1,2-epoxy propane. One component of the mixture is not defined in the database of the simulation program. For synthesis and simulation of this process, it is necessary to have (1) the component TePG defined as a chemical structure, (2) the physical and transport properties of this component, and (3) vapor-liquid equilibrium data for the components of the mixture. © 2013 American Chemical Society.
Oprea M.,Petroleum Gas University of Ploiesti
International Journal of Artificial Intelligence | Year: 2012
Artificial intelligence provides a variety of techniques and methods that can be implemented in the environmental decision support systems, for solving different problems such as forecasting, analysis, diagnosis, control and planning, for a better quality of the environment and, thus, of the life. The paper presents an intelligent system, INTELLEnvQ-Air that was developed for air quality analysis in urban regions and for informing the population about the impact of air pollution on human health and possible measures of protection for vulnerable persons. The system integrates two artificial intelligence approaches: feed forward artificial neural networks, for air pollutants concentrations forecasting, and rule-based expert systems for the analysis of air quality and human health impact. © 2012 by IJAI (CESER Publications).
Popa C.,Petroleum Gas University of Ploiesti
Procedia Engineering | Year: 2014
This paper presents an application of plantwide control strategy for a complex process, like catalytic cracking process. The plantwide control strategy assists the engineer in determining how to choose the best manipulated, controlled and measured variables in the plant, when is using advanced control techniques such MPC. The result of applying plantwide control to catalytic cracking process is a hierarchical control structure, which is organized on three levels, with two advanced control techniques for the second level. From economic point of view, the development and the implementation a hierarchical control structure for the catalytic cracking process is leading to increase plant efficiency. © 2014 The Authors. Published by Elsevier Ltd.
Toader F.A.,Petroleum Gas University of Ploiesti
2014 International Conference on Development and Application Systems, DAS 2014 - Conference Proceedings | Year: 2014
Production scheduling is an important part of the production management in the manufacturing systems area for the reason that its main objective is to increase the productivity and to minimize the operating costs. In this paper it is presented a swarm intelligence approach over the job shop scheduling problem, by using Ant Colony Optimization and Particle Swarm Optimization techniques. Due to the high complexity of this problem an optimal solution, that solves the resources conflicts and minimizes the makespan and total completion time, is difficult to obtain. In this context a comparison between the two implemented techniques is presented in order to evaluate the performance considering different simulation production scenarios. © 2014 IEEE.