Giuseppe Giunta

The smart gas grid: state of the art and perspectives

The main objective of this paper is to illustrate the current state of the art of the newborn smart gas grid concept. We provide a detailed discussion of the envisaged features of the smart gas grid, giving attention to both the related academic literature and to the ongoing world-wide projects. In doing so, we also discuss the potentialities of rethinking the smart grid paradigm from the perspective of a whole energy system, that both encompasses the electrical and the gas grid, and identify some critical key aspects that must be handled while developing the new smart energy paradigm.

Clustering analysis of the electrical load in european countries

In this paper we used clustering algorithms to compare the typical load profiles of different European countries in different day of the weeks. We find out that better results are obtained if the clustering is not performed directly on the data, but on some features extracted from the data. Clustering results can be exploited by energy providers to tailor more attractive time-varying tariffs for their customers. In particular, despite the relevant differences among the several compared countries, we obtained the interesting result of identifying a single feature that is able to distinguish weekdays from holidays and pre-holidays in all the examined countries.

Advanced Pipeline Vibroacoustic Monitoring

Remote real-time monitoring of pipelines reliability is becoming a key factor for the environmental sustainability of oil&gas industry. Multipoint Acoustic Sensing (MAS) technology makes use of multi sensors placed at discrete distances to detect Third Party Interference (TPI) and fluid leaks along the pipeline. In fact, any interaction with the pipe generates pressure waves that are guided within the fluid (gas or oil) for long distances, carrying information on the source event. Pressure propagation is mainly governed by the absorption coefficient and the sound speed. These parameters are in turn complicated functions of the frequency, the geometrical and elastic parameters of the pipe shell, the elastic parameters of the surrounding medium, and the acoustic and thermodynamic properties of the transported fluid. We have analyzed these aspects while processing acoustic data collected on crude oil and gas transportation pipelines, in different operational and flow conditions. This study describes the acquisition campaigns and the data analysis steps used for the experimental derivation of fluid properties and pipe anomalies. The results are also used for the validation of mathematical models of pressure waves propagation in fluid filled pipes.Copyright

Pipeline Health Integrity Monitoring (PHIM) Based on Acoustic Emission Technique

The Acoustic Emission (AE) technique allows taking under control the damage as superficial flaws (S-Flaws) occurred during service operation of remarkable zones of steel components, monitoring the initiation and the propagation of critical defects, submitted to static or variable stresses and aggressive environment exposure.In the framework of the eni gas&power research project oriented to the development of a “AE methodology” for monitoring critical sections of gas transmission pipelines, a study has been carried out jointly with Centro Sviluppo Materiali (CSM), aimed to investigate reliability and applicability of the AE technique to steels used in the Oil&Gas industry.Steel grades API 5L X65, X80 and X100, representative of traditional and new gas pipelines, have been selected. The project was scheduled investigating the potential of these steels to release elastic waves generated by sources of damage related to ductile or brittle fracture mechanisms.Hydraulic tests until failure were carried out on single pipes using steel grade API 5L X65 for monitoring the growing of the damage on the tip of artificial surface notches (S-flaw), machined on the wall thickness [1]. Water was used as internal fluid and temperature effect was considered as well. The capability of the AE technique to discriminate ductile and brittle fractures, the essential information to approach an integrity assessment procedure, was achieved. This paper, respect to the previous ones [1], extends the AE methodology for monitoring pipelines supplying both oil and gas. In fact a third burst test was carried out filling the pipe by air and the results on this item are presented.Copyright

A Multi-Objective Method for Short-Term Load Forecasting in European Countries

In this paper we present a novel method for daily short-term load forecasting, belonging to the class of “similar shape” algorithms. In the proposed method, a number of parameters are optimally tuned via a multi-objective strategy that minimizes the error and the variance of the error, with the objective of providing a final forecast that is at the same time accurate and reliable. We extensively compare our algorithm with other state-of-the-art methods. In particular, we apply our approach upon publicly available data and show that the same algorithm accurately forecasts the load of countries characterized by different size, different weather conditions, and generally different electrical load profiles, in an unsupervised manner.

Accurate Monitoring of Pipe and Structural Vibrations by Remote RADAR Observations

The paper describes an innovative RADAR-based methodology to monitor vibrations in pipes and structures. RADARs sense vibrations from zero to thousands of kHz with a spatial sensitivity that goes down to a few micrometers in the best cases and they never saturates even for very large motions. Furthermore, they do it remotely, say tens of meters. The paper provides a critical analysis of performance of such technique and a cross-validation with both controlled vibration in laboratories and measures from accelerometers in campaigns in compression gas stations.Copyright

Advanced three dimensional monitoring of structural vibrations and displacements by remote radar sensing

The possibility of remotely sensing vibrations and displacements of industrial and civil infrastructures by exploiting electro-magnetic energy, has received new interest in the last years. In fact, preliminary experiments demonstrate that such a technique, not yet being fully investigated, is quite promising and could provide very accurate results with respect to the system currently being used (e.g. accelerometers). In fact, a radar sensor is able to provide a very accurate estimation of the Line of Sight displacements by continuously monitoring the distance between targets lying on the structures, and radar itself. This paper provides an insight into the potentialities of such a technique for accurate three-dimensional monitoring of structural vibrations and displacements.

Gas Filled Pipelines Monitoring Using Multipoint Vibroacoustic Sensing

eni S.p.A. has promoted and supported a research project (DIONISIO) for the design of a proprietary pipeline monitoring system, exploiting negative pressure waves and statistical analysis principles. A discrete network of pressure and vibration sensors are installed on the pipeline, at relative distances of tens of kilometers. The acoustic and elastic waves produced by third party interference and by flow variations (leaks, spills, valve regulations, pig operations, etc.), propagate along the pipeline, and they are recorded at the monitoring stations. Multichannel processing of the collected signals enables the real time detection, localization and classification of the triggering event.The system has been tested in single phase and multiphase transportation lines during several field campaigns. This paper collects the results for gas transportation pipelines.The field experience has been used to upgrade the prototypal version of the system to an industrial version, that is currently operative, or in an advanced installation phase, on several pipelines in Italy and in Nigeria, and it has detected tens of bunkering activities with a localization accuracy of about 25 m, from a distance up to 35 km from the sensing point.Copyright

Advanced Real Time and Long Term Monitoring of Transportation Pipelines

A key factor for the sustainable development of oil&gas industry is the remote monitoring of integrity and reliability of transportation pipelines. In order to mitigate the risk associated to third party interference (TPI) risks and to minimize the environment exposure, it is possible to deploy a Multipoint Acoustic Sensing (MAS) technology which makes use of multi sensors placed at discrete distances along the pipeline. Any interaction with the pipe generates acoustic waves that are guided within the fluid (gas, oil, products or water) for long distances, providing information on the source event and on the “transmission” channel. Acoustic propagation is mainly governed by both absorption coefficient and sound speed, which in turn are functions of the pipe, fluid and surrounding medium system. These features have been analyzed by processing real-time data collected with a proprietary MAS system (e-vpms™) on fluid transportation pipelines, in different operational and flow service conditions, producing exhaustive sets of TPI actions, leak trials and tracking pig inspections. The paper presents original procedures for real-time monitoring, as well as for long term supervision and advance intervention planning.

Analysis of Corrosion Areas in Pipelines Using Guided Wave Propagation: Numerical Simulations and Experimental Tests

Guided Waves (GW) have become widely used for the inspection of unpiggable and inaccessible pipelines because of the presence of coating, because of their position or because they are buried.Among the possible anomalies, corrosion is the main integrity issue affecting pipelines. The effect that corrosion has on guided wave propagation is attenuation and increased coherent noise when it is generalized or reflection when corrosion is localized.In this paper, the possibility to characterize corrosion areas affecting pipelines through long range guided wave inspection or monitoring is investigated. With this purpose field testing was performed and the results were used for the validation of numerical methods able to simulate the phenomenon.Copyright