Numerical Simulation of Sulfur Deposit with Particle Release

Sulfur deposition commonly occurs during the development of a high-sulfur gas reservoirs. Due to the high gas flow velocity near the wellbore, some of the deposited sulfur particles re-enter the pores and continue to migrate driven by the high-speed gas flow. The current mathematical model for sulfur deposition ignores the viscosity between particles, rising flow caused by turbulence, and the corresponding research on the release ratio of particles. In order to solve the above problems, firstly, the viscous force and rising force caused by turbulence disturbance are introduced, and the critical release velocity of sulfur particles is derived. Then, a release model of sulfur particles that consider the critical release velocity and release ratio is proposed by combining the probability theory with the hydrodynamics theory. Notably, based on the experimental data, the deposition ratio of sulfur particles and the damage coefficient in the sulfur damage model are determined. Finally, a comprehensive particle migration model considering the deposition and release of sulfur particles is established. The model is then applied to the actual gas wells with visible sulfur deposition that target the Da-wan gas reservoir, and the results show that the model correctly reflects flow transport during the process of sulfur deposition in porous media. In addition, through the numerical simulation experiments, it was found that considering the release of sulfur particles reduces the saturation of sulfur particles within a specific range around the well and improve the reservoir permeability in this range. From the perspective of gas production rate, the release of sulfur particles has a limited effect on the gas production rate, which is mainly due to the sulfur particle release being limited, having only a 5 m range near the wellbore area, and thus the amount of gas flow from the unaffected area is basically unchanged.

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A Laboratory Plant for Gas Liquefaction

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132515500108 ◽

2015 ◽

Vol 23 (02) ◽

pp. 1550010 ◽

Cited By ~ 2

Author(s):

M. De Salve ◽

D. Milani ◽

B. Panella ◽

G. Roveta

Keyword(s):

High Speed ◽

Gas Flow ◽

Time History ◽

Gas Production ◽

Point Of View ◽

Plant Performance ◽

Condensation Process ◽

In Series ◽

Energetic Point ◽

Main Components

A prototype gas liquefaction plant has been designed and manufactured for Politecnico di Torino cryogenic laboratory and has been used for cryogenic applications like superconducting cables and low temperature refrigeration devices. The plant is able to liquefy nitrogen and, by means of little changes, hydrogen and other cryogenic fluids too. The thermal energy is removed by four high speed (up to 360 000 revolutions per minute) helium turbines that are connected in series. The gas liquefaction is carried out by the cooling condensation process of the gas flow that feeds a 0.15 m3 super insulated tank that is cooled inside. The cryogenic system is based on the Claude and Collins cycles, fed with helium that provides the cold sink. The paper shows the characteristics of the plant main components, and the time history of the measured temperatures, pressures, and flow rates during the plant start-up, as well as the steady state liquefied gas production rate. From the energetic point of view, the plant performance is acceptable for a research laboratory and the plant efficiency is not far from that of commercial larger size plants.

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Numerical Simulation Research of Air-Assisted Atomizer Internal Gas Flow Field Based on Fluent

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.599-601.377 ◽

2014 ◽

Vol 599-601 ◽

pp. 377-380

Author(s):

Qiao Li ◽

Ya Yu Huang

Keyword(s):

Numerical Simulation ◽

Flow Field ◽

Total Pressure ◽

High Speed ◽

Gas Flow ◽

Static Pressure ◽

Mutual Influence ◽

Simulation Research ◽

Simulation Calculation ◽

Gas Flow Field

The numerical simulation calculation of air-assisted atomizer internal gas flow field is done, the distribution and changes of the nozzle inside flow field total pressure, velocity, and dynamic and static pressure are analyzed. The analysis shows that the total pressure loss is less; due to the effect of gas viscous, the high-speed air flow is formed vortex flow near the outlet nozzle and the mutual influence between the dynamic and static pressure. A new way is supported for optimizing the nozzle structure according to these studies.

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Numerical Simulation of the Effect of Different Numbers of Inlet Nozzles on Vortex Tubes

Processes ◽

10.3390/pr9091531 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1531

Author(s):

Qijun Xu ◽

Jing Xie

Keyword(s):

Numerical Simulation ◽

High Speed ◽

Gas Flow ◽

Three Dimensional ◽

Maximum Velocity ◽

Vortex Chamber ◽

Inlet Pressure ◽

Energy Separation ◽

Outlet Temperature ◽

Vortex Tubes

In order to broaden the application of vortex tubes (VOTU) in industry and to improve the efficiency of cooling and heating, numerical simulations of vortex tubes were carried out. In this study, the temperature, velocity, and pressure fields of three VOTUs with inlet nozzles of 2, 3, and 6 were investigated at different inlet pressures based on previous experimental data and by three-dimensional numerical simulation. It was found that the increase of inlet pressure leads to the increase of energy separation between the hot and cold ends of the three VOTUs. As the number of inlets increases, the pressure difference between the tube wall and the core region gradually strengthens. In contrast, the pressure in the tube center is not affected by the inlet pressure. The number of nozzles affects the inlet and outlet temperatures of the VOTU. When the number of nozzles is 3, and the inlet pressure is 0.6 MPa, the VOTU shows the maximum hot and cold outlet temperature difference of 66 K. The maximum velocity of VOTU appears at the connection of the inlet and vortex chamber, so the inlet is tangential to VOTU, which is beneficial to reduce the loss of gas energy. The wall thickness of the inlet increases gradually to avoid the high-speed gas flow on the erosion of the wall surface. This study has profound guidance for the one-dimensional design of VOTUs.

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The Influence of Determining Factors on the Parameters of Gas-lift Operation of Flooded Gas Wells

Prospecting and Development of Oil and Gas Fields ◽

10.31471/1993-9973-2020-1(74)-72-81 ◽

2020 ◽

pp. 72-80

Author(s):

R. М. Kondrat ◽

О. R. Kondrat ◽

L. І. Khaidarova ◽

N. М. Hedzyk

Keyword(s):

Production Rate ◽

Flow Rate ◽

Gas Flow ◽

Gas Production ◽

Gas Flow Rate ◽

Gas Wells ◽

Research Results ◽

Wellhead Pressure ◽

Water Factor ◽

Gas Lift

The development of gas deposits at the final stage is usually complicated by watering production wells. With the advent of water in the formation product, the gas production rate decreases due to the decrease in the gas-saturated thickness of the reservoirs and the increase in pressure loss during movement of the liquid-gas mixture in the wellbore and flow lines as compared to the movement of gas only. Well operation is gradually becoming unstable, periodic with the subsequent cessation of natural flowing. The methods of operation of flooded wells are characterized. The use of the gas-lift method for the operation of flooded gas wells in depleted gas fields is justified. The effect of tubing diameter, wellhead pressure and water factor on the parameters of gas-lift operation of flooded wells is investigated. The research is carried out using the improved technique proposed by the authors and the PipeSim program for hypothetical (simulated) well conditions. The studies performed are presented in the form of graphical dependences of the production rate of reservoir gas, the minimum required gas production rate for the liquid to be taken from the bottom of the well to the surface, lift gas flow rate and bottomhole pressure on wellhead pressure, diameter of tubing and water factor. The research results indicate a significant coincidence of the values of the calculated parameters of the gas-lift operation of the watered well according to the proposed methods and the PipeSim program. Using the research results, it is possible to select the optimal diameter of the tubing string and evaluate the value of formation gas flow rate and gas-lift flow rates for various values of water factor and wellhead pressure.

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Influence of Pore Structure and Solid Bitumen on the Development of Deep Carbonate Gas Reservoirs: A Case Study of the Longwangmiao Reservoir in Gaoshiti–Longnusi Area, Sichuan Basin, SW China

Energies ◽

10.3390/en13153825 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3825

Author(s):

Jianxun Chen ◽

Shenglai Yang ◽

Dongfan Yang ◽

Hui Deng ◽

Jiajun Li ◽

...

Keyword(s):

Pore Structure ◽

Production Rate ◽

Gas Flow ◽

Loss Rate ◽

Sedimentary Environment ◽

Gas Production ◽

Accumulation Process ◽

High Permeability ◽

Gas Reservoirs ◽

Solid Bitumen

A variable sedimentary environment and accumulation process leads to a complex pore structure in deep carbonate gas reservoirs, and the physical properties are quite different between layers. Moreover, some pores and throats are filled with solid bitumen (SB), which not only interferes with reservoir analysis, but also affects efficient development. However, previous studies on SB mainly focused on the accumulation process and reservoir analysis, and there are few reports about the influence on development. In this paper, through scanning electron microscope analysis, SB extraction, gas flow experiments and depletion experiments, and a similar transformation between experimental results and reservoir production, the production characteristics of carbonate gas reservoirs with different pore structures were studied, and the influence of SB on pore structure, reservoir analysis and development were systematically analyzed. The results show that permeability is one of the key factors affecting gas production rate and recovery, and the production is mainly contributed by high-permeability layers. Although the reserves are abundant, the gas production rate and recovery of layers with a low permeability are relatively low. The SB reduces the pore and throat radius, resulting in porosity and permeability being decreased by 4.73–6.28% and 36.02–3.70%, respectively. With the increase in original permeability, the permeability loss rate decreases. During development, the loss rate of gas production rate is much higher than that of permeability. Increasing the production pressure difference is conducive to reducing the influence. SB also reduces the recovery, which leads to the loss rate of gas production being much higher than that of porosity. For reservoirs with a high permeability, the loss rates of gas production rate and the amount produced are close to those of permeability and porosity. Therefore, in the reservoir analysis and development of carbonate gas reservoirs bearing SB, it is necessary and significant to analyze the influence of reservoir types.

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Numerical Simulation of Solid Particle Erosion in a 90 Degree Bend for Gas Flow

Volume 6A: Pipeline and Riser Technology ◽

10.1115/omae2014-23656 ◽

2014 ◽

Cited By ~ 6

Author(s):

Ri Zhang ◽

Haixiao Liu

Keyword(s):

Experimental Data ◽

Numerical Simulation ◽

Solid Particle ◽

Gas Flow ◽

Computational Models ◽

Oil And Gas ◽

Simulation Method ◽

Gas Production ◽

Solid Particle Erosion ◽

Particle Erosion

Solid particle erosion in piping systems is a serious concern of integrity management in the oil and gas production, which has been widely predicted by the numerical simulation method. In the present work, every step of the comprehensive procedure is verified when applied to predicting the bend erosion for gas flow, and improvements are made by comparing different computational models. Firstly, five turbulent models are implemented to model the flow field in a 90 degree bend for gas flow and examined by the static pressure and velocity profile measured in experiments. Secondly, the particle velocities calculated by fully coupling and one-way coupling are compared with experimental data. Finally, based on the knowledge of flow modeling and particle tracking, four classic erosion equations are introduced to calculate the penetration rates in a 90 degree bend. By comparing with the experimental data available in the literature, it indicates that the k–ε model is the most accurate and effective turbulent model for gas pipe flow; the fully coupling makes the simulation of particle motion closer to measured data; and the Grant and Tabakoff equation presents better performance than other equations.

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Numerical Simulation of Flow Field in Cylinder of Gasoline Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.826 ◽

2012 ◽

Vol 220-223 ◽

pp. 826-829

Author(s):

Yun Jing Jiao ◽

Man Qun Lin ◽

Xuan Wang ◽

Xue Yan Wang ◽

Xi Cheng Yan

Keyword(s):

Numerical Simulation ◽

High Speed ◽

Gas Flow ◽

Gasoline Engine ◽

Transient State ◽

Simulation Software ◽

Maximum Torque ◽

Compression Stroke ◽

Crank Angle ◽

The Stability

Abstract: By adopting CFD numerical simulation software, the transient state numerical simulation of engine is carried on. The intake and compression stroke are studied in maximum power and maximum torque conditions. Through numerical simulation, we can learn the change of TKE with the crank angle, and give a guide for improving design of intake port and chamber. At last, a conclusion is found about the engine that at high speed, the gas flow in cylinder infects the stability of spark ignition.

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