Determination of optimal oil pumping plans

This paper presents the results of determining the optimal plans for pumping oil through the main oil pipelines of Kazakhstan. The calculation methodology is based on determining the minimum unit cost of pumping depending on oil flow rate. Oil pumping energy-saving modes are determined under optimal operating conditions of pumping units and heating furnaces at stations. Determination of the optimal pumping plan is implemented as a separate module of the SmartTranPro software. Pumped oil volumes on the oil pipeline sections were determined on the basis of the automated system of control and metering of electrical energy data of KazTransOil JSC. Optimal pumping plans for monthly oil volumes in the Kalamkas – Karazhanbas and Dzhumagaliev – Atasu pipeline sections for cold and warm periods were calculated on the basis of the found dependence of the pumping unit cost. For each range of oil mass flow rate, specific costs for oil pumping and a list of operating pumps at oil pumping stations located along the pipeline section are indicated.

Improving the compact heat exchangers with profiled tubes for marine power plants

The design features of heat exchangers with flat tubes are considered. The stages of creating a new flat tube and its prototypes are analyzed. An oil refrigerator is chosen as a prototype of the heat exchanger because of the previous use of flat tubes with wells, now replaced with new flat profiled tubes. Thermal and hydraulic tests of a refrigerator made of such tubes are carried out at the stand. During the testing, the hydraulic resistance of the cavities of the cooled and cooling media and thermal parameters are determined: heat power, heat transfer coefficient and heat transfer coefficient from the cooled medium in the inter-tube cavity with the transverse flow of tubes to the tube wall. A satisfactory correspondence of the actual power values determined for both working environments has been established. The discrepancy does not exceed (-7.6%)-(+5%) with an average value of +0.2%. A satisfactory correspondence of the actual and calculated values of the refrigerator power has been obtained. The discrepancy does not exceed (-15%)-(+9%) with an average value of -2.8%. The calculation of the capacity of the refrigerator during its operation in the design mode of oil cooling is carried out. The oil flow is considered both through the pipe and through the inter-pipe space. A good convergence of the calculations with the experimental results has been revealed.

Карта режимов течения вода-нефть в прямом микроканале

The flow regimes of water and crude oil in a Y-type microchannel were studied in a wide range of flow rates. Four different types of water-oil flow regimes have been identified: plug, droplet, parallel and chaotic. The ranges of existence of these flow regimes have been determined. Dependences of the length of water plugs and droplets in oil on various parameters have been established. Maps of the corresponding water-oil flow regimes have been constructed.

THREE DIMENSIONAL SIMULATION OF OIL FLOW CHARACTERISTICS IN LUBRICATION SYSTEM OF ROTARY TILLAGE ENGINE

Taking the lubrication system of rotary tillage engine as the research object, this paper makes a three-dimensional simulation study on the oil flow characteristics in the lubricating oil passage. The oil supply of the oil pump shall be greater than the circulating oil required by the lubrication system to ensure the lubrication of the rotary cultivator. Lubrication system is an important part to ensure the reliability and durability of rotary cultivator. The key component to achieve its performance is the oil pump. The geometric model of lubricating oil flow field in rotary tiller lubrication system is established by using FLUENT software. The results show that the pressure drop in the lubricating oil passage of the main bearing is the largest under the same working conditions. In the oil passage of the cylinder head, the pressure drop of the front main oil passage is the largest and the oil discharge is the largest. Add 1.6mm oil pump rotor on the basis of the thickness of the original oil pump rotor, the oil flow at the connecting rod nozzle reaches the flow index of the original rotary cultivator, and there is no cylinder pulling phenomenon of the rotary cultivator.

Optimization and Sensitivity Analysis of the Cutting Conditions in Rough, Semi-Finish and Finish Honing

Honing processes are currently employed to obtain a cross-hatched pattern on the internal surfaces of cylinders that favors oil flow in combustion engines or hydraulic cylinders. The main aim of the present paper is to optimize the machining conditions in honing processes with respect to surface roughness, material removal rate and tool wear by means of the desirability function. Five process variables are considered: grain size, density, pressure, linear speed and tangential speed. Later, a sensitivity analysis is performed to determine the effect of the variation of the importance given to each response on the results of the optimization process. In the rough and semi-finish honing steps, variations of less than 5% of the importance value do not cause substantial changes in the optimization process. On the contrary, in the finish honing step, small changes in the importance values lead to modifications in the optimization process, mainly regarding pressure. Thus, the finish honing phase is more sensitive to changes in the optimization process than the rough and the semi-finish honing phases. The present paper will help users of honing machines to select proper values for the process variables.

Numerical Simulation of Two-Phase Water-Oil Flow in a Horizontal Pipe Using the Smoothed Particle Hydrodynamics Method

In this work, the numerical code DualPhysics, based on the Lagrangian particle and mesh free method Smoothed Particle Hydrodynamics, has been employed to solve the slightly compressible isothermal two-phase water-oil flow. The continuity and momentum equations are solved, and we used the modified Tait equation of state to determine the pressure. To validate the numerical code, we solved the modified Couette flow of two fluids. As a practical case, we solved the isothermal and two-dimensional two-phase water-oil flow. The mixing of the fluids occurs after passing through a 45 degree Y junction placed at the entrance of the horizontal pipeline. Results showed the potential for using the numerical code, although some modifications and alterations are still necessary to solve practical problems.

Recovery Improvement Using Geological, Technical and Operational Factors of Field Development That Influence the Character of Inflow Profiles in Horizontal Laterals

Currently, it is hard to imagine oil field development management without various surveys, involving resource optimisation for more economical reserves recovery. In this context, the application of new technologies aimed at diagnostics of the state of producing wells opens up multiple opportunities to identify the causes of premature water flooding and reduction in oil production, clarify the geology of the developed deposit, and obtain other useful information in a cost-efficient manner. For several decades now, well logging has been the source of information for field operators on the producing reservoir performance and the composition of fluid flowing across the reservoir through target intervals. However, in the course of time, the industry tends to seek advanced technologies and alternative production logging techniques for well performance diagnostics. Marker-based production logging is just one of the techniques employed to obtain additional data that can be extremely important for prompt decision-making in case of any complicating factors. At the same time, such information requires proper processing and interpretation. The information on how various factors impact the production profile helps develop a set of measures to adjust the oil flow into the well. In this regard, the task above offers a promising outlook for improving the development system efficiency using selective reservoir stimulation, as far as unconventional reservoirs and hard-to-recover reserves are concerned. Therefore, the upstream industry puts a strong focus on further research in this area today.

Thermally Controlled Fluid to Reduce Formation Breakdown Pressures in Tight Gas Reservoirs

High breakdown pressure is one of the major challenges in deep tight gas reservoirs. In certain wells, achieving breakdown pressures within the completion tubular yield limit is not possible, and those zones may have to be abandoned without fracturing. Using thermally controlled fluid can lower the formation temperature and ultimately reduce the stresses of the tight gas reservoir formation near the wellbore. The objective of this study is to prove numerically that having a cooled near-wellbore region is a feasible and effective solution to reduce the breakdown pressure. An integrated hydraulic fracturing and reservoir simulator that has been developed at the University of Texas at Austin is utilized for this study. The simulator is a non-isothermal, multi-phase black-oil flow in reservoir, fracture, and wellbore domains. It was found that using thermally controlled fluid is effective in reducing breakdown pressure. Bottomhole Pressure (BHP) decreased by up to around 60% when the temperature of the near-wellbore region is reduced by 60 °F under the simulated conditions in this study. Injecting thermally controlled fluid did not only reduce the high breakdown pressure but also improve the hydraulic fractures efficiency and complexity. This technique is novel and has not been studied in depth in the literature. Utilizing thermally controlled fluid can be a cost effective solution to reduce high breakdown pressure in tight gas reservoirs.

Meso-Cenozoic negative inversion model for the Linhe Depression of Hetao Basin, China

The Linhe Depression is the largest tectonic unit in the Hetao Basin. The recently discovered commercial oil flow in the structural trap of wells JH2X and S5 has proved that the Meso-Cenozoic strata in the Linhe Depression have great exploration potential. Research on the kinematic model for the Mesozoic–Cenozoic Linhe Depression is important for analysing the geological conditions of hydrocarbon accumulation. In this study, field observations, seismic interpretation and scaled analogue modelling are performed. The results prove that the Linhe Depression experienced different stages of tectonic evolution, such as compressional depression (K1l), conversion from contraction to uniform subsidence (K1g), extensional rifting (E2–N2) and strike-slip deformation (Q), during the Mesozoic–Cenozoic eras. The kinematic model of negative inverted basins was first established with the early differential compression superimposed by the late extension. The seismic interpretation and analogue modelling results show that Jilantai Sag in the southern part of the Linhe Depression was subjected to compression from the Bayanwulashan fold–thrust belt on the NW side and the Helanshan fold–thrust belt on the SE side during Early Cretaceous time. Meanwhile, the Hanghou Sag in the northern part of the Linhe Depression was only compressed by the Langshan fold–thrust belt from the NW direction. The rifted structure generated by the extension from the SE direction during the Cenozoic Era resulted in the negative inversion of the pre-existing thrusts in different patterns. The intensity of negative inversion is controlled by several key factors, such as dip angle and the patterns of thrust faults, along with different basement textures. The morphological changes in the forebulge zone developed during Early Cretaceous time are responsible for the development of the segmented Central fault zones in the Hanghou Sag.

Examination of Viscosity Effect on Cavitating Flow inside Poppet Valves Based on a Numerical Study

The higher susceptibility to cavitation in poppet valves due to the lower viscosity of water than the traditionally used mineral oil poses a challenge in fluid transmission technology. To reveal the underlying mechanism of cavitating flow physics associated with the variation in viscosity effect, the current paper examines both the water and oil cavitating flow dynamics inside poppet valves with varied structures through a numerical study. The simulation results are validated with a comparison to previous experimental data in terms of cavitation morphology and pressure distribution. According to the predicted cavitation distribution, three kinds of cavitation occurred at separated positions in both water- and oil-flow cases. The vortex cavitation, which in the oil-flow case displays a remarkable paired structure with favorable coherence, is featured with a scattered dispersion in the water-flow case, while the profound attached cavitation at the poppet trailing edge in the water-flow case almost disappears in the oil-flow case. Furthermore, the attached cavitation within the chamfered groove has higher stability in the oil-flow case, compared to the thorough detachment behavior featured with profound 3-dimensionality in the water-flow case. According to the potential core and vortex evolution, the strong 3-dimensionality due to the violent laminar-turbulent transition in the water-flow case together with the produced puff pattern of the potential core, to a large extent, interrupts the periodic behavior of cavitation, which is essentially preserved in the oil-flow case featured with favorable coherence.