The energy consumption of oil collection increases rapidly after oilfield enters the stage of high water cut. Carrying out gathering and transportation at normal or low temperature can save cost and ...bring certain enterprise benefit. In order to judge whether the gathering and transportation can be carried out at normal or low temperature, the thermodynamic hydraulic calculation model is constructed and modified according to the field measured data. Then the thermally hydraulic coupling calculation is carried out to determine the gathering and transportation radius. The single factor sensitivity analysis method was used to rank the sensitivity of the factors influencing the gathering and transportation radius, and the radius chart is made. The results show that the modified thermo-hydraulic model can better predict the temperature and pressure drop, and the average error of the calculated and the measured value is 2.5% and 7.67%. The four most influential factors from strong to weak are starting point temperature, liquid yield, moisture content of mass and ambient temperature. The chart drawn by the factors provides the basis for the normal temperature gathering and transportation of the pipeline, so the required temperature at the start of the pipe can be determined by querying the chart.
IMPROVED MATHEMATICAL MODEL OF THE MAIN PIPELINE WITH LOOPING Roman A. Shestakov; Konstantin S. Rezanov; Yulia S. Matveeva ...
Izvestiâ Tomskogo politehničeskogo universiteta. Inžiniring georesursov,
02/2022, Letnik:
333, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The relevance of the research. In the modern world, pipeline transportation of oil and petroleum products occupies a leading position and it is an important aspect of the industry not only of the ...Russian Federation, but of the whole world. However, despite all its advantages, there are also significant disadvantages, including those related to the operation of pipeline systems and the accuracy of determining the technological parameters of the pipeline during mathematical modeling in operation and design. In this regard, the development of new and improving the accuracy of existing mathematical models of pipeline systems are urgent tasks of designing and operating pipeline systems, including when designing looping. The main aim of the research is the investigation of the influence of local resistances arising at the points of connection of the looping to the main line of the pipeline on increasing the throughput capacity of the section of the main oil pipeline between two oil pumping stations by laying the looping. Methods: mathematical modeling of the main pipeline section operation taking into account local resistances at the looping connection points and without taking them into account, as well as a comparative analysis of the results obtained by constructing three-dimensional dependencies. Results. A refined mathematical model of the inter-station section of the pipeline with looping, through which oil or petroleum products are pumped, has been developed. The authors have constructed a three-dimensional graph of the dependence of the deviation in calculation results of the looping length of the standard and refined models on the length and diameter of the laid looping. An economic assessment of the additional length of the looping was carried out and three-dimensional dependences of profit on the diameter and length of the looping were constructed, taking into account transshipment operations and without them.
A distributed-framework basin modeling system (DFBMS) was developed to simulate the runoff generation and movement on a basin scale. This study is part of a series of papers on DFBMS that focuses on ...the hydraulic calculation methods in runoff concentration on underlying surfaces and flow movement in river networks and lakes. This paper introduces the distributed-framework river modeling system (DF-RMS) that is a professional modeling system for hydraulic modeling. The DF-RMS contains different hydrological feature units (HFUs) to simulate the runoff movement through a system of rivers, storage units, lakes, and hydraulic structures. The river network simulations were categorized into different types, including one-dimensional river branch, dendritic river network, loop river network, and intersecting river network. The DF-RMS was applied to the middle and downstream portions of the Huai River Plain in China using different HFUs for river networks and lakes. The simulation results showed great consistency with the observed data, which proves that DF-RMS is a reliable system to simulate the flow movement in river networks and lakes.
The relevance of research. At present, the role of activities aimed to improving the reliability of equipment in the main pipeline transport of natural gas is growing. The factor that negatively ...affects the reliability of operation of compressor stations equipment of main gas pipelines is the increased vibration due to various reasons. One of these reasons is the combination of certain geometric dimensions of pipelines and high flow of process gas. The aim of the research is to define the modes of a compressor manufactory with 8 full-pressure units to reduce the intensive dead-end oscillation observed in off-cycle compressor units’ piping. Object: pipeline communications section of the compressor station from the cyclone dust collectors to the inlet manifold of the compressor manufactory, tees with branches to the gas-pumping unit, switched off by cranes No. 1 from the inlet manifold. Methods: vibration diagnostics of piping at the existing compressor station; mathematical modeling of operating modes of the compressor manufactory using a numerical solution (hydraulic calculation in combination with the calculation of natural frequencies and frequencies of the driving force). Findings. The paper proposes a method for eliminating dead-end oscillations within the scope of operation, specifying the requirements of regulatory documentation. The methodology for estimating the conditions of dead-end oscillations appearance is developed. It is based on the hydraulic calculation of a high-pressure loop gas pipeline with selections. Two modes of a compressor manufactory with 8 full-pressure units with a capacity of 100 million m3 / day are considered to detuning from resonance. As a result of the calculations, the number of gas-pumping units from the edge of the compressor manufactory, that must be operated to eliminate dead-end oscillations, has been reduced in comparison with the recommendations of normative documentation. This allows putting the second gas-pumping unit from the edge of the compressor manufactory into reserve and, consequently, reducing the operating time of this gas-pumping unit while eliminating the high dead-end oscillations of the piping.
A regional water supply network (RWSN) plays a key role in the process of urbanization development. This paper researches the planning optimization model of a regional water supply network with the ...payoff characteristic between economical cost and reliability, in which the hydraulic-connectivity is selected as the surrogate measure of the reliability in the regional water supply network. The modified artificial fish swarm algorithm (MAFSA) is proposed to solve the optimization problem by adjusting research visual and the inertia weights of artificial fish swarm algorithm (AFSA) according to the hydraulic-connectivity. The experiment results of regional water supply network show that MAFSA can effectively obtain the optimal solution with the maximum reliability and least cost compared to other algorithms, which can thereby achieve the optimization of RWSN engineering applications.
The most expensive portion of a large-scale district cooling system is the distribution network that conveys chilled-water to multiple buildings at controlled rates for use in comfort cooling. As the ...piping system needs large initial investment cost, a thorough investigation would be required to properly design the network. In order to come up with the solution a methodology for an optimal design of district cooling distribution network with loop-type system is needed. In this study, a district cooling distribution network model with loop-type system was investigated by calculating the system pressure drop, system volumetric flow rate and volumetric flow rate for each building. Friction factor identification, system simulation and optimization were performed based on the design temperature difference of 9°C with supply temperature of 4.5°C. The governing equations consisted of mass conservation, performance curve of variable primary flow pumping scheme, energy equations due to pipe friction and an equation that indicates the algebraic sum of head losses around any closed loop must be zero. Multivariable Newton-Raphson method was used to solve the system of nonlinear equations with the elements of solution vector determined using singular-value decomposition method. Exhaustive search method was used to solve the objective function and subsequently determine the piping network design criteria that yields minimum overall cost. Numerical results were also compared with traditional methods and have found some degree of similarities of pipe sizes except for pressure drop values exceeding 100 Pa/m.
The purpose of the study is to identify the hydraulic resistance coefficient of the main oil pipeline. Oil transportation through pipelines is the most efficient way to deliver oil from suppliers to ...consumers. The volume of transported oil depends on the pipeline hydraulic resistance. In practice, the hydraulic resistance coefficient is determined by the value of the Reynolds number and the pipeline internal surface roughness. The Reynolds number depends on the oil viscosity, which changes in a non-isothermal pipeline due to the heat exchange of the oil flow with the environment. The pipeline internal surface roughness changes during main oil pipeline operation. The identification of the pipeline hydraulic resistance coefficient is necessary for accurate calculations of the technological modes of the main oil pipeline. The SCADA (supervisory control and data acquisition) system determines the actual oil data (pressure, temperature, flow rate) along the main oil pipeline length in real time. Based on the results of the thermal-hydraulic calculations and the SCADA system, the hydraulic resistance coefficient identification method was built. The methodology was tested in the OPS-3-Koschagil, Severnye Buzachi-Karazhanbas, Prorva-Kultumiyev, Kassymov-Bolshoi Chagan main pipeline sections. The approbation results have shown sufficient accuracy in identifying the hydraulic resistance coefficient of oil pipelines. The obtained hydraulic resistance coefficient dependences were used to determine the oil transportation technological modes in industrial pipelines.
This article presents a method of collaborative one-dimensional (1D)–three-dimensional (3D) modeling of computational fluid dynamics. The method is based on the simultaneous calculation of 3D and 1D ...areas and linking the two parts of the problem by transferring the boundary conditions. The 3D approximation region is modeled based on the solution of Navier-Stokes equations. The 1D regions are calculated using the basic conservation laws and the empirical characteristics of elements. The proposed solutions are validated through several tasks. For each task, the results are compared with the available analytical solutions or the experimental data.
Territory protection against flood water inundation and creation of polder systems are carried out with the help of protection dikes. One of the main requirements to the composition of polder systems ...in flood plains is a location of border dikes beyond meander belt in order to avoid their erosion when meander development occurs. Meander belt width can be determined on the basis of the analysis of multi-year land surveying pertaining top river-bed building and in the case when such data is not available this parameter is calculated in accordance with the Snishchenko formula. While banking-up a river bed a flooded area is decreasing and, consequently, water level in inter-dike space and rate of flood water are significantly increasing. For this reason it is necessary to locate dikes at a such distance from a river bed which will not cause rather high increase in water level and flow velocity in the inter-dike space. Methodology for hydraulic calculation of river regulation has been developed in order to substantiate design parameters for levee systems, creation of favourable hydraulic regime in these systems and provision of sustainability for dikes. Its main elements are calculations of pass-through capacity of the leveed channel and rise of water level in inter-dike space, and distance between dikes and their crest level. Peculiar feature of the proposed calculated formulae is an interaction consideration of channel and inundated flows. Their mass-exchanging process results in slowing-down of the channel flow and acceleration of the inundated flow. This occurrence is taken into account and coefficients of kinematic efficiency are introduced to the elements of water flow rate in the river channel and flood plain, respectively. The adduced dependencies for determination of a dike crest level (consequently their height) take into consideration a rise of water level in inter-dike space for two types of polder systems: non-inundable (winter) dikes with maximum spring flood rate and inundable (summer) dikes with summer-autumn flood rates. The proposed calculated formulae can be recommended for application at design organizations.
PDF
