Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Numerical and laboratory experimental analysis of the movement of silicone cleaning pigs through 90-degree bends pipe

Stetsiuk S.M., Doroshenko Ya.V., Filipchuk O.O., Daniv Z.V., Volovetskyi V.B.

Archives of Materials Science and Engineering

2024

Vol. 126, nr 2

65--77

Purpose: Analysis of the stress-strain state of cylindrical cleaning pigs manufactured of hyperelastic material during their movement through the pipe bends of the pipelines, identification of maximum contact forces' points, and places of their separation from the inner wall. The effect of the dynamic friction coefficient between the pig's lateral surface and the pipeline's inner wall on the value of the maximum equivalent von Mises stresses in the pig is investigated – determination of the required pressure for the passage of the pig through pipeline bends. Design/methodology/approach: The finite element method performs numerical modelling of the pigs' movement through pipeline bends is performed. The non-linear properties of a hyperelastic pig material (a silicone compound with a hardness of 30 units on the Shore scale) are described by the potential Yeoh strain energy model. The contact interaction of the pig with the inner wall of the pipe bend is modelled by a surface-to-surface contact with dynamic friction coefficients of 0.1, 0.2, and 0.3 between them. For research, pigs with a length of 60 mm, 75 mm and 90 mm with a convex front and a concave rear end were manufactured and modelled. The experimental unit was designed and mounted from metal and glass pipes, between which pipe bends were placed with a bending angle of 90° and a bending radius of 1.5 DN. The metal pipeline has an internal diameter of 49 mm and a total length of 5.3 m, and the glass pipeline is 54 mm and 5 m, respectively. The experimental installation made of glass pipes was designed for visual observation of the dynamics of the pig movement through the glass pipeline bend and from metal – for measuring the pressure during the pig movement along the straight sections and the pipeline bend. To verify the correctness of the numerical modelling, the fully calculated deformations of the cleaning pigs in the bends of the pipeline were visualized and compared with photographs of the deformations of the pigs during their movement through the glass bends of the pipelines. Findings: The bending of the pig in the pipe bend and contact forces increase equivalent von Mises stresses in the pig. Moreover, during the movement of the pig in a pipe bend, the distribution of equivalent von Mises stresses in it, as well as its deformations, changes continuously. It depends on the stage at which it is located. Numerical modelling and experiments have established that when the pig is at the stage of movement in the middle part of the pipe bend, due to bending, its lateral surface is partially separated from the inner wall of the pipe bend. With this, on the convex side of the pipe bend, the pig is separated from the wall in the front and rear parts and on the concave side – in the middle part. This separation of the lateral surface of the pig from the inner wall of the pipe bend results in the formation of a gap and cross-flows through the pig, reducing the pressure drop on it, which can lead to its sticking. For pigs made of silicone compound with a hardness of 30 units on the Shore scale to pass pipeline bends with a bending angle of 90° and a bending radius of 1.5 DN, the pressure in the pig space shall be at least twice as high as the pressure required for the pig to move along a straight section of the pipeline. Research limitations/implications: Modelling and experimental studies were performed for pigs made of silicone compound. Therefore, subsequent studies will establish the influence of other hyperelastic materials' physical and mechanical properties on the pig movement along the pipeline bends. Practical implications: The results obtained in this study allow for determining the possibility of pigs passing through the pipeline bends of gas gathering systems at gas fields and gas networks, determining the necessary pressure for this and, if necessary, optimising the geometric shape and dimensions of the pigs passing through the pipe bends. Originality/value: The influence of the location of a solid pig made of hyperelastic material in the pipeline bend and the coefficient of dynamic friction on the stress-strain state of the pig is studied. The article contains original experimental units designed and installed to study the movement of pigs through pipeline bends.

Development of methods for predicting hydrate formation in gas storage facilities and measures for their prevention and elimination

Volovetskyi V. B., Doroshenko Ya. V., Matkivskyi S. V., Raiter P. M., Shchyrba O. M., Stetsiuk S. M., Protsiuk H. Ya.

Journal of Achievements in Materials and Manufacturing Engineering

2023

Vol. 117, nr 1

25--41

Purpose: The purpose of this work is to study the processes of hydrate formation during the operation of wells and underground gas storage facilities. Development of a set of measures aimed at the prediction and timely prevention of hydrate formation in wells and technological equipment of gas storage facilities under different geological and technological conditions. Design/methodology/approach: The prediction of hydrate formation processes was carried out using a neural network that is a software product with weight factors calculated in MATLAB environment and the ability to adapt parameters of the network specified to updated and supplemented input data during its operation. So, within the MATLAB software environment, a software module of a two-layer artificial neural network with a random set of weight factors is created at the first stage. In the second stage, the neural network is trained using experimental field input/output data set, output data. In the third stage, an artificial neural network is used as a means of predicting hydrate formation with the ability to refine weight factors during its operation subject to obtaining additional updated data, as an input set, for modifying the coefficients and, accordingly, improving the algorithm for predicting of an artificial neural network. In the absence of new data for the additional training of an artificial neural network, it is used as a computing tool that, on the basis of input data about the current above-mentioned selected technological parameters of fluid in the pipeline, ensures the output values in the range from 0 to 1 (or from 0 to 100%), that indicates the probability of hydrates formation in the controlled section of the pipeline. Application of such an approach makes it possible to teach; additionally that is, to improve the neural network; therefore this means of predicting hydrate formations objectively increases reliability of results obtained in the process of predicting and functioning of the system. The authors of the work recommend to carry out an integrated approach to ensure clear control over the operation mode of wells and gas collection points. Findings: According to the results of experimental studies, the places of the most likely deposition of hydrates in underground gas storage facilities were identified, in particular, in the inside space of the flowline in places of accumulation of liquid contaminants (lowered pipeline sections) and an adjustable choke of the gas collection point. The available methods used to prevent and eliminate hydrate formation both in wells and at gas field equipment were analyzed. Such an analysis made it possible to put together a list of methods that are most appropriate for the conditions of gas storage facilities in Ukraine. The method of predicting hydrate formation in certain sections of pipelines based on algorithms of artificial neural networks is proposed. The developed methodology based on data on values of temperatures and pressures in certain sections of pipelines allows us to predict the beginning of the hydrate formation process at certain points with high accuracy and take appropriate measures. Research limitations/implications: To increase the efficiency of solving the problem of hydrate formation in gas storage facilities, it is expedient to introduce new approaches to timely predict complications, in particular, the use of neural networks and diverse measures. Practical implications: Implementation of the developed predicting methodology and methods and measures to prevent and eliminate hydrate formation in wells and technological equipment in underground gas storage facilities will increase the operation efficiency of underground gas storage facilities. Originality/value: The use of artificial intelligence to predict hydrate formations in flowlines of wells and technological equipment of underground gas storage facilities is proposed. Using this approach to predict and function the system as a whole ensures high reliability of the results obtained due to adaptation of the system to the specified control conditions.

Development of foam-breaking measures after removing liquid contamination from wells and flowlines by using surface-active substances

Volovetskyi V. B., Doroshenko Ya. V., Stetsiuk S. M., Matkivskyi S. V., Shchyrba O. M., Femiak Y. M., Kogut G. M.

Journal of Achievements in Materials and Manufacturing Engineering

2022

Vol. 114, nr 2

67--80

Purpose: The purpose is to consider the complications that arise during the operation of gas condensate wells, in particular, the accumulation of liquid contamination. Development of new approaches to improve the efficiency of the separation equipment performance of gas gathering and treatment systems when a multiphase flow enters. Development of a foam breaking method in a gas-liquid flow after removal of liquid contaminants from wells and flowlines using surfactants. Design/methodology/approach: An analysis was made of the complications that may arise when removing liquid contaminants from wells and flowlines using surfactants. Measures have been developed that will make it possible to timely prevent the ingress of foam into the separation equipment of gas gathering and treatment systems. Using computational fluid dynamics (CFD) modelling, an effective foam-breaking device was developed by supplying stable hydrocarbon condensate. Findings: A method to minimize the negative impact of foam on the operation of separation equipment after fluid removal from wells and gas condensate field flowlines using a surfactant solution was elaborated. A method for its breaking was proposed to prevent the flow of foam into the gas processing unit. This method foresees the application of the technological scheme layout for supplying a stable hydrocarbon condensate to a gas-liquid flow entering the separators of the first of separation, both the main line and the measuring line. CFD modelling was used to study the process of foam breaking by feeding hydrocarbon condensate into it. The influence of the hydrocarbon condensate supplying method on gas-dynamic processes (distribution of pressure, velocity, volumetric particles of phases), and the efficiency of foam breaking was estimated. It was established that the supply of hydrocarbon condensate from one branch pipe to the pipeline through which the foam moved did not ensure its complete breaking. To increase the efficiency of foam breaking, a device with designed four nozzles for supplying hydrocarbon condensate was developed. CFD modelling made it possible to substantiate that in this case, a pressure reduction zone appeared at the place of condensate supply. Because of a sharp change in pressure, a strong improvement in the effect of foam breaking occurred. The understanding of the regularities of foam breaking processes by hydrocarbon condensate was obtained, and the design of a device for the complete foam breaking was developed. Research limitations/implications: The obtained results of laboratory studies have shown that a sharp decrease in the stability of the foam occurs under the condition of an increase in the volume of stable hydrocarbon condensate added to the studied model of mineralized formation water. Based on the results of CFD modeling, a device for breaking foam by stable hydrocarbon condensate has been worked out, the effectiveness of which will be confirmed experimentally and in field conditions. Practical implications: The results of the performed laboratory studies and CFD modelling allow a more reasonable approach to using various available methods and measures to prevent the ingress of foam with a gas-liquid flow into the separation equipment of gas gathering and treatment systems. This approach makes it possible to develop new effective ways and measures to prevent this complication. Originality/value: Based on CFD modelling, it was found that when a stable hydrocarbon condensate is supplied into a gas-liquid flow, foam breaks. A method for breaking foam in a gas-liquid flow has been developed, which is original and can be introduced in practice.