期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
Direct Calculation of Unsteady-State Weymouth Equations for Gas Volumetric Flow Rate with Different Friction Factors in Horizontal and Inclined Pipes 被引量:3
1
作者 Abayomi O. Olatunde Tunde A. Adeosun +4 位作者 Mohammed A. Usman Olabisi M. Odunlami Moses A. Olowofoyeku Testy E. Ekakitie Atanda M. Mohammed 《Engineering(科研)》 2012年第4期202-209,共8页
Direct calculations of unsteady-state Weymouth equations for gas volumetric flow rate occur more frequently in the design and operation analysis of natural gas systems. Most of the existing gas pipelines design proced... Direct calculations of unsteady-state Weymouth equations for gas volumetric flow rate occur more frequently in the design and operation analysis of natural gas systems. Most of the existing gas pipelines design procedures are based on a particular friction factor and steady-state flow analysis. This paper examined the behavior of different friction factors and the need to develop model analysis capable of calculating unsteady-state gas flow rate in horizontal and inclined pipes. The results show different variation in flow rate with Panhandle A and Panhandle B attaining stability in accurate time with initial unsteadiness at the instance of flow. Chen and Jain friction factors have opposition to flow with high flow rate: The prediction also reveals that Colebrook-White degenerated to Nikuradse friction factor at high Reynolds number. The horizontal and inclined flow equations are considerably enhanced on the usage of different friction factors with the aid of Matlab to handle these calculations. 展开更多
关键词 unsteady-state Flow Rate Friction Factor Stability VARIATIONS UNSTEADINESS
下载PDF
Research on properties of hollow glass microspheres/epoxy resin composites applied in deep rock in-situ temperature-preserved coring 被引量:3
2
作者 Zhi-Qiang He Yang Yang +7 位作者 Bo Yu Jian-Ping Yang Xiang-Biao Jiang Bo Tian Man Wang Xi-Yuan Li Si-Qing Sun Hui Sun 《Petroleum Science》 SCIE CAS CSCD 2022年第2期720-730,共11页
Deep petroleum resources are in a high-temperature environment.However,the traditional deep rock coring method has no temperature preserved measures and ignores the effect of temperature on rock porosity and permeabil... Deep petroleum resources are in a high-temperature environment.However,the traditional deep rock coring method has no temperature preserved measures and ignores the effect of temperature on rock porosity and permeability,which will lead to the distortion of the petroleum resources reserves assessment.Therefore,the hollow glass microspheres/epoxy resin(HGM/EP)composites were innovatively proposed as temperature preserved materials for in-situ temperature-preserved coring(ITP-Coring),and the physical,mechanical,and temperature preserved properties were evaluated.The results indicated that:As the HGM content increased,the density and mechanical properties of the composites gradually decreased,while the water absorption was deficient without hydrostatic pressure.For composites with 50 vol%HGM,when the hydrostatic pressure reached 60 MPa,the water absorption was above 30.19%,and the physical and mechanical properties of composites were weakened.When the hydrostatic pressure was lower than 40 MPa,the mechanical properties and thermal conductivity of composites were almost unchanged.Therefore,the composites with 50 vol%HGM can be used for ITPCoring operations in deep environments with the highest hydrostatic pressure of 40 MPa.Finally,to further understand the temperature preserved performance of composites in practical applications,the temperature preserved properties were measured.An unsteady-state heat transfer model was established based on the test results,then the theoretical change of the core temperature during the coring process was obtained.The above tests results can provide a research basis for deep rock in-situ temperature preserved corer and support accurate assessment of deep petroleum reserves. 展开更多
关键词 Deep rock in-situ temperature-preserved coring(ITP-Coring) Hollow glass microspheres/epoxy resin composites Hydrostatic pressure unsteady-state heat transfer model
下载PDF
Effect of solidification process parameters on dry sliding wear behavior of AlNiBi alloy 被引量:2
3
作者 T.M.BOTELHO H.M.AZEVEDO +4 位作者 G.H.MACHADO C.R.BARBOSA F.S.ROCHA T.A.COSTA O.L.ROCHA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第3期582-594,共13页
As-cast samples of the Al-3wt.%Ni-lwt.%Bi alloy resulting from the horizontal directional solidification process were subjected to the micro-abrasive wear test.The effects of the solidification thermal and microstruct... As-cast samples of the Al-3wt.%Ni-lwt.%Bi alloy resulting from the horizontal directional solidification process were subjected to the micro-abrasive wear test.The effects of the solidification thermal and microstructural parameters,such as the growth and cooling rates and the cellular and primary dendritic spacings(VL and TR;λ1 and λc;respectively),were evaluated in the wear resistance of the investigated alloy.The tribological parameters analyzed were the wear volume and rate(Vw and Rw).The solidification experiments and the wear tests were carried out by means of a water-cooled horizontal directional solidification device and a rotary-fixed ball wear machine,respectively.The results show lower Vw and Rw values correspond to finer microstructures and the Vw dependence on λ1 is characterized by an experimental mathematical equation.A better distribution of Bi soft droplets and Al3Ni hard intermetallic particles is observed within the finer interdendritic region and,in consequence,the better wear resistance is achieved in as-cast samples with dendritic morphology rather than cellular morphology.A transition of wear mechanism from adhesive to abrasive is observed. 展开更多
关键词 unsteady-state horizontal solidification dry sliding wear cellular/dendrite arm spacing MICROHARDNESS Bi particle Al_(3)Ni particle
下载PDF
Effect of Heat-Insulating Layer Thickness on Melting Rate of Ice Fixed Abrasives Polishing Pad 被引量:1
4
作者 赵研 左敦稳 +1 位作者 孙玉利 王珉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第4期415-420,共6页
The formula of the thickness of the heat-insulating layer is deduced via heat transfer analysis,according to the principle of heat transfer in limited space.Polishing experiments are carried out using the same technol... The formula of the thickness of the heat-insulating layer is deduced via heat transfer analysis,according to the principle of heat transfer in limited space.Polishing experiments are carried out using the same technological parameters.Compared with the polishing experimental results,the heat transfer model is proved to be correct.As validated by the experimental results,polyurethane heat-insulating layer can effectively improve the service life of the ice fixed abrasive pad and alleviate the melting rate in the polishing process to improve the polishing quality proposed.The heat transfer model provides theoretical basis for research of temperature field of ice fixed abrasive polishing. 展开更多
关键词 ice fixed abrasive heat-insulating layer unsteady-state conduction
下载PDF
Passive simulation method of turbine flow sensors based on the 6-DOF model 被引量:1
5
作者 Guo Suna Ji Zengqi +3 位作者 Liu Xu Wang Fan Zhao Ning Fang Lide 《Journal of Southeast University(English Edition)》 EI CAS 2022年第3期242-251,共10页
A passive simulation method based on the six degrees of freedom(6-DOF)model and dynamic mesh is proposed according to the working principle to study the dynamic characteristics of the turbine flow sensors.This simulat... A passive simulation method based on the six degrees of freedom(6-DOF)model and dynamic mesh is proposed according to the working principle to study the dynamic characteristics of the turbine flow sensors.This simulation method controls the six degrees of freedom of the impeller using the user-defined functions(UDF)program so that it can only rotate under the impact of fluid.The impeller speed can be calculated in real-time,and the inlet speed can be set with time to obtain the dynamic performance of the turbine flow sensors.Based on this simulation method,three turbine flow sensors with different diameters were simulated,and the reliability of the simulation method was verified by both steady-state and unsteady-state experiments.The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results.The deviation between the simulation and experiment results is low,with a maximum deviation of 2.88%.In the unsteady simulation study,the impeller speed changed with the inlet velocity of the turbine flow sensor,showing good tracking performance.The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor. 展开更多
关键词 turbine flow sensor computational fluid dynamics(CFD) dynamic performance unsteady-state flow simulation method
下载PDF
Research and applications of FDMP algorithm for power quality signal analysis 被引量:1
6
作者 赵勇 王学伟 +2 位作者 王琳 韩东 陆以彪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第1期87-93,共7页
The accuracy of unsteady-state disturbance analysis of power quality signals is reduced by the steadystate components with high amplitudes and energies. In this paper,a novel frequency-domain matching pursuits (FDMP) ... The accuracy of unsteady-state disturbance analysis of power quality signals is reduced by the steadystate components with high amplitudes and energies. In this paper,a novel frequency-domain matching pursuits (FDMP) algorithm is proposed to estimate the parameters of the steady-state components and separate the unsteady-state disturbances from power quality signals. Firstly,the time-frequency atoms and redundant dictionaries are constructed according to the characteristics of power quality signal spectra. Secondly,the steady-state components and unsteady-state disturbances of power quality signals are decomposed by FDMP into two mutually orthogonal subspaces in Hilbert space. Furthermore,the expressions for parameters calculation of steady-state components have been derived. The experiments show that the relative errors of frequency and amplitude estimations of steady-state components are less than 2 × 10 -4 and 5 × 10 -3 respectively,and phase estimation errors are less than 1. 6° under the existence of both interharmonics and unsteady-state disturbances. The steady-state components and unsteady-state disturbances are separated quickly and accurately. 展开更多
关键词 Power quality unsteady-state disturbance matching pursuits (MP) frequency-domain matching pursuits (FDMP) time-frequency atom
下载PDF
Simulation Method of Dynamic Characteristics of Turbine Flow Sensor
7
作者 GUO Suna JI Zengqi +3 位作者 LIU Xu WANG Fan ZHAO Ning FANG Lide 《Instrumentation》 2021年第3期1-15,共15页
Computational Fluid Dynamics(CFD)simulation is one of the important methods to study the performance and influencing factors of turbine flow sensors.According to the working characteristics of the turbine flow sensor,... Computational Fluid Dynamics(CFD)simulation is one of the important methods to study the performance and influencing factors of turbine flow sensors.According to the working characteristics of the turbine flow sensor,the passive simulation method based on the six degrees of freedom(6-DOF)model and dynamic mesh is proposed in this paper.The reliability of the simulation method is verified by steady-state experiments and unsteady-state experiments.The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results,and the deviation between the simulation result and the experiment result is low with a maximum deviation of 2.88%.In the unsteady simulation study,the impeller speed changes with the inlet velocity of the turbine flow sensor,which has a good follow-up.The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor. 展开更多
关键词 Turbine Flow Sensor CFD Dynamic Performance unsteady-state Flow Simulation Method
原文传递
Phase Prediction of Supercritical Carbon Dioxide and its Application in Fracturing Oil Wellbores 被引量:3
8
作者 GONG Liang CHEN Shichao +2 位作者 ZUO Jiaqiang BAI Bin BAI Zhang 《Journal of Thermal Science》 SCIE EI CAS CSCD 2019年第3期484-493,共10页
In recent oil and gas exploration, the most reservoirs are low permeability with abundant reserves. Conventional mining of low permeability reservoir is commonly utilizing the hydraulic fracturing technology, whereas,... In recent oil and gas exploration, the most reservoirs are low permeability with abundant reserves. Conventional mining of low permeability reservoir is commonly utilizing the hydraulic fracturing technology, whereas, it encounters various technical issues, such as clay expansion and water lock damage. Using the fluid of supercritical carbon dioxide(S-CO_2) to exploit the low permeability oil and gas reservoirs is attracting more attention. The implementation of S-CO_2, without liquid phase, can help avoid the aforementioned problems. Nevertheless, the phase change of CO_2 during fracturing is complicate, and it is difficult to accurately predict the CO_2 phase transition. In this work, first, the physical properties of S-CO_2 were analyzed by the Span-Wagner model and Vesovic model. Next, S-CO_2 was applied to a typical oilfield, and an unsteady coupling model of heat transfer and pressure drop was developed. Then the staggered grid method and iteration procedures were used for numerical solutions, and the temperature and pressure distributions of wellbores were investigated. The results indicate that the temperature control of a wellbore is the key to the phase prediction of S-CO_2; CO_2 within the single-diameter pipeline below 2300 m can maintain the supercritical state, while CO_2 within the stepped pipeline can maintain the supercritical state at the depth of 2280 m. Moreover, compared with the single-diameter pipeline, the bottom pressure of the stepped pipeline is lower and the bottom temperature is higher. By analyzing the flow and heat transfer of S-CO_2 in the wellbores, the phase state of S-CO_2 was well predicted, which is helpful to improve the exploring performance of low permeability oil and gas reservoirs. 展开更多
关键词 SUPERCRITICAL carbon dioxide unsteady-state heat transfer PHASE PREDICTION wellbore
原文传递
Productivity model for gas reservoirs with open-hole multi-fracturing horizontal wells and optimization of hydraulic fracture parameters 被引量:3
9
作者 Jianqiang Xue Nianyin Li +2 位作者 Xiaobing Lu Suiwang Zhang Yong Wang 《Petroleum》 2017年第4期454-460,共7页
Multi-fractured horizontal wells are commonly employed to improve the productivity of low and ultra-low permeability gas reservoirs.However,conventional productivity models for open-hole multi-fractured horizontal wel... Multi-fractured horizontal wells are commonly employed to improve the productivity of low and ultra-low permeability gas reservoirs.However,conventional productivity models for open-hole multi-fractured horizontal wells do not consider the interferences between hydraulic fractures and the open-hole segments,resulting in significant errors in calculation results.In this article,a novel productivity prediction model for gas reservoirs with open-hole multi-fractured horizontal wells was proposed based on complex potential theories,potential superimposition,and numerical analysis.Herein,an open-hole segment between two adjacent fractures was regarded as an equivalent fracture,which was discretized as in cases of artificial fractures.The proposed model was then applied to investigate the effects of various parameters,such as the angle between the fracture and horizontal shaft,fracture quantity,fracture length,diversion capacity of fractures,horizontal well length,and inter-fracture distance,on the productivity of low permeability gas reservoirs with multi-fractured horizontal wells.Simulation results revealed that the quantity,length,and distribution of fractures had significant effects on the productivity of low permeability gas reservoirs while the effects of the diversion capacity of fractures and the angle between the fracture and horizontal shaft were negligible.Additionally,a U-shaped distribution of fracture lengths was preferential as the quantity of fractures at shaft ends was twice that in the middle area. 展开更多
关键词 Low permeability gas reservoir Multi-fractured horizontal well Productivity prediction Open-hole completion unsteady-state flow Fracture parameters optimization
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部