scholarly journals Evaluation of the effectiveness of anti-turbulent additives in the oil pipeline transportation

2020 ◽  
Vol 157 ◽  
pp. 02005
Author(s):  
Aleksei Balabukha ◽  
Valentina Zvereva

The authors of the article have developed the computer application allows to determine the value of the friction coefficient λ and anti-turbulent additives efficiency with a high degree of accuracy. The program can be used in the calculations and design of oil pipelines. The paper presents experimental studies of the effect anti-turbulent additives on the magnitude of pressure losses during fluid movement through pipes. The data gained by the developed computer program has been proved by the data of practical application of additives in the real oil pipeline transportation system called Eastern Siberia-Pacific Ocean oil pipeline.

Author(s):  
L. Poberezhny ◽  
R. Martyniuk ◽  
A. Stanetsky ◽  
L. Poberezhna ◽  
O. Tkach ◽  
...  

Purpose: Due to changes in the volume of oil transportation, part of the pipelines must be temporarily decommissioned. The purpose of the work is theoretical and experimental study of pressure fluctuations during operation of oil pipelines and their impact on the durability of the pipeline material in work state and after temporary decommissioning (conservation). Design/methodology/approach: The results of oil pressure fluctuation research have given a chance to choose the terms of experimental research providing of the pipe metal mechanical features changes research during oil pipeline exploitation. Findings: Fatigue test modes are selected based on the calculations of the mathematical model developed. Experimental studies of the dependence of the fatigue strength of the pipe material on the conditions of operation have been carried out, which made it possible to determine the parameters of the fatigue curve of the samples. Has been defined that fatigue strength for the new metal pipe samples is more for 20-25% than for the metal samples which had the contacts with lime milk and for 30-40% more than for metal samples which were under exploitation. Research limitations/implications: In the future, more combination of "pipe material – preservation medium" should be explored to establish pain of general regularities. Practical implications: The probabilistic curves of the pipeline non-destruction are constructed, which will be used for practical calculations of the reliability and durability of the 13G1S-U steel pipelines. Originality/value: Mathematical model is made that describes non-stationary oil moves in oil pipeline, that has been caused by jump like changes of oil supply in oil pipeline, on this basis was defined, that oil pressure in oil pipeline provides within non stationary process in a range of 0.4-0.6 Hz frequency and amplitude fluctuation of pressure is 0.1-0.5 MPa.


Author(s):  
V. Т. Bolonnyi

The characteristics of Ukrainian oil transportation system are presented; the emergency risks of Ukrainian oil pipelines are established. The analysis of the accident rate of oil pipeline transportation in Ukraine, Russia and the USA was carried out. The processes of initiation and progression of man-made emergencies in Ukraine during the oil pipelines operation are considered. The article presents the technique of specifying the incidental pressure in a pipeline, depending on the amount of oil loss at the site of oil leaks. It gives an opportunity to calculate the amount of oil loss and to evaluate the environmental hazards caused by oil pipeline transportation emergencies.  It is based on the equations of motion and continuity of fluid flow. This technique makes it possible to calculate the pressure at each point of a pipeline in transient mode caused by changes in pressure at the beginning and at the end of the section and the emergence of concentrated oil offtake. It also gives an opportunity to monitor the change in mode parameters along the pipeline under conditions of pipeline depressurization. Maximum discrepancy in calculation results becomes typical when the range of fluctuations is maximal. It has been established that discrepancy increases when the distance from the source of perturbation becomes bigger. The discrepancy in calculation results is practically non-existent for the pressure fluctuations at the point of perturbation start (). Based on the results of calculations, the author constructs a graph of pressure change of the oscillatory process in the oil pipeline caused by the jump in the pressure at the beginning and at the end of the section, and the presence of probable leaks at the certain point of the pipeline route. The line section of the main oil pipelines is the most dangerous part since all emergencies are associated with emergency processes of different intensity in the form of outflow of oil into the environment, and are dangerous because of system breakdowns can take place. Both the process of the generation of the oil pollution zone and its time period depend on the amount of oil leakage, its intensity and depth of the oil pipeline.


Author(s):  
O. Yu. Kichigina

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.


2011 ◽  
Vol 8 (1) ◽  
pp. 201-210
Author(s):  
R.M. Bogdanov

The problem of determining the repair sections of the main oil pipeline is solved, basing on the classification of images using distance functions and the clustering principle, The criteria characterizing the cluster are determined by certain given values, based on a comparison with which the defect is assigned to a given cluster, procedures for the redistribution of defects in cluster zones are provided, and the cluster zones parameters are being changed. Calculations are demonstrating the range of defect density variation depending on pipeline sections and the universal capabilities of linear objects configuration with arbitrary density, provided by cluster analysis.


Robotica ◽  
2015 ◽  
Vol 35 (2) ◽  
pp. 463-482 ◽  
Author(s):  
Avinash Siravuru ◽  
Suril V. Shah ◽  
K. Madhava Krishna

SUMMARYThis paper discusses the development of an optimal wheel-torque controller for a compliant modular robot. The wheel actuators are the only actively controllable elements in this robot. For this type of robots, wheel-slip could offer a lot of hindrance while traversing on uneven terrains. Therefore, an effective wheel-torque controller is desired that will also improve the wheel-odometry and minimize power consumption. In this work, an optimal wheel-torque controller is proposed that minimizes the traction-to-normal force ratios of all the wheels at every instant of its motion. This ensures that, at every wheel, the least traction force per unit normal force is applied to maintain static stability and desired wheel speed. The lower this is, in comparison to the actual friction coefficient of the wheel-ground interface, the more margin of slip-free motion the robot can have. This formalism best exploits the redundancy offered by a modularly designed robot. This is the key novelty of this work. Extensive numerical and experimental studies were carried out to validate this controller. The robot was tested on four different surfaces and we report an overall average slip reduction of 44% and mean wheel-torque reduction by 16%.


2021 ◽  
Vol 410 ◽  
pp. 287-292
Author(s):  
Anatolij A. Babenko ◽  
Leonid A. Smirnov ◽  
Alena G. Upolovnikova

The equilibrium interfacial distribution of sulfur and boron was estimated using the HSC 6.1 Chemistry software package (Outokumpu) and the simplex-lattice planning method. Adequate mathematical models have been constructed in the form of III degree polynomial, which describe the effect of the composition of the studied oxide system on the equilibrium distribution of sulfur and boron between the slag and the metal. Generalization of the results of experimental studies and thermodynamic modeling made it possible to obtain new data on the influence of the basicity and content of B2O3 in the slag of the CaO-SiO2-B2O3-MgO-Al2O3 system on the interphase distribution of sulfur and boron. It was found that in the range of boron oxide concentration of 1.0-10%, an increase in slag basicity from 2 to 5 at 1600°C leads to an increase in the sulfur distribution coefficient from 1 to 20 and, as a consequence, a decrease in the sulfur content in the metal from 0.02 to 0.0014 %, i.e. an increase in slag basicity favorably affects the development of the metal desulfurization process. An increase in the B2O3 content from 2.0 to 10.0% in slags formed in the region of moderate basicity, not exceeding 2-3, is accompanied at 1600°C by a decrease in the boron interphase distribution coefficient from 450 to 150 and an increase in the boron concentration in the metal from 0.006 to 0.021 %, which indicates the progress of boron reduction from slag to metal. The shift of the formed slags to the area of ​​increased basicity up to 5.0 shows a high degree of boron reduction from slag to metal. The results of the laboratory experiment confirmed the results of thermodynamic modeling.


2021 ◽  
pp. 38-55
Author(s):  
A. V. Vlasenko ◽  
E. A. Evdokimov ◽  
E. P. Rodionov

The paper summarizes data on modern approaches to the diagnosis, prevention and treatment of severe acute parenchymal respiratory failure of various origins, including ARDS due to bacterial viral pneumonia. The work is based on the data of modern well-organized studies, analysis of international clinical guidelines with a high degree of evidence, as well as the results of our own long-term experimental studies and clinical observations of the treatment of patients with ARDS of various origins, including viral pneumonia of 2009, 2016, 2020. Scientifically grounded algorithms for prevention, differential diagnosis and personalized therapy of severe acute respiratory failure using innovative medical technologies and a wide range of respiratory and adjuvant treatment methods have been formulated. The authors tried to adapt as much as possible the existing current recommendations for the daily clinical practice of anesthesiologists and resuscitators.


Author(s):  
Марат Замирович Ямилев ◽  
Азат Маратович Масагутов ◽  
Александр Константинович Николаев ◽  
Владимир Викторович Пшенин ◽  
Наталья Алексеевна Зарипова ◽  
...  

Теплогидравлический расчет неизотермических трубопроводов является наиболее важным гидравлическим расчетом в рамках решения задач обеспечения надежности и безопасности работы нефтепроводной системы. Для практических расчетов применяются формулы Дарси - Вейсбаха и Лейбензона. При этом в ряде случаев (короткие теплоизолированные участки, поверхностный обогрев нефтепроводов) можно использовать упрощенный подход к расчету, пренебрегая изменением температуры или учитывая температурные поправки. В настоящее время формулы для аналитического расчета движения высоковязких нефтей в форме уравнения Лейбензона получены только для ньютоновской и вязкопластичной жидкостей. Для степенной жидкости соответствующие зависимости отсутствуют, расчет ведется с использованием формулы Дарси - Вейсбаха. Целью настоящей статьи является представление формулы Дарси - Вейсбаха для изотермических течений степенной жидкости в форме уравнения Лейбензона. Данное представление позволит упростить процедуру проведения аналитических выкладок. В результате получены модифицированные уравнения Лейбензона для определения потери напора на участке нефтепровода в диапазоне индекса течения от 0,5 до 1,25. В указанном диапазоне относительное отклонение от результатов расчетов с использованием классических формул Метцнера - Рида и Ирвина не превышает 2 %. The thermal-hydraulic calculation of non-isothermal pipelines is the most important hydraulic calculation in the framework of solving the problems of ensuring the reliability and safety of the oil pipeline system. For practical calculations, the Darcy - Weisbach and Leibenson formulas are used. Moreover, in a number of cases (short heat-insulated sections, surface heating of oil pipelines), a simplified approach to the calculation can be used, neglecting temperature changes or taking into account temperature corrections. At present, formulas for the analytical calculation of the motion of high-viscosity oils in the form of the Leibenson equation have been obtained only for Newtonian and viscoplastic fluids. For a power-law fluid, there are no corresponding dependences; the calculation is carried out using the Darcy - Weisbach formula. The purpose of this article is to present the Darcy - Weisbach formula for isothermal flows of a power-law fluid in the Leibenzon form, which will simplify the procedure for performing analytical calculations. The modified Leibenzon equations are obtained to determine the head loss in the oil pipeline section in the range of the flow index from 0.5 to 1.25. In the specified range, the relative deviation from the results of calculations using the classical Metzner - Reed and Irwin formulas does not exceed 2 %.


Author(s):  
C. Stuart Daw ◽  
K. Dean Edwards ◽  
Robert M. Wagner ◽  
Johney B. Green

Spark assist appears to offer considerable potential for increasing the speed and load range over which homogeneous charge compression ignition (HCCI) is possible in gasoline engines. Numerous experimental studies of the transition between conventional spark-ignited (SI) propagating-flame combustion and HCCI combustion in gasoline engines with spark assist have demonstrated a high degree of deterministic coupling between successive combustion events. Analysis of this coupling suggests that the transition between SI and HCCI can be described as a sequence of bifurcations in a low-dimensional dynamic map. In this paper, we describe methods for utilizing the deterministic relationship between cycles to extract global kinetic rate parameters that can be used to discriminate multiple distinct combustion states and develop a more quantitative understanding of the SI-HCCI transition. We demonstrate the application of these methods for indolene-containing fuels and point out an apparent HCCI mode switching not previously reported. Our results have specific implications for developing dynamic combustion models and feedback control strategies that utilize spark assist to expand the operating range of HCCI combustion.


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