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141.
岩石液压致裂中几个问题的研究 总被引:1,自引:1,他引:0
论证了流体压力变化与岩石强度变化之间的关系,阐述了流体保持与释放的应力条件和构造环境,总结了两种围岩下的液压致裂模型及其流量方程。 相似文献
142.
聚醚多元醇钻井液研制及应用 总被引:6,自引:3,他引:3
以新研制的多功能聚醚多元醇SYP-1为主剂,对聚合物包被剂、防塌剂和降滤失剂进行了优选实验.在此基础上,研制了一种新型的聚醚多元醇钻井液.对聚醚多元醇钻井液的抑制性、流变性、滤失造壁性、润滑性以及对油气层的保护性能进行了室内评价实验,并分析了该钻井液的作用机理.在LN3-6H井和HD4-23H井进行的聚醚多元醇钻井液现场试验表明,在钻进过程中井壁稳定,井径规则,起、下钻畅通,井下安全,测井、下套管及固井作业顺利.室内实验和现场应用表明,聚醚多元醇钻井液具有优良的防塌性和润滑性,能有效地抑制岩屑分散,起到稳定井壁和保护油气层的作用,满足复杂地质条件下钻井的需要. 相似文献
143.
Fluid catalytic cracking (FCC) is one of the most complex processes in the petroleum industry. The large degree of uncertainty in the kinetics of the cracking reactions and catalyst deactivation by coke deposition in the riser reactor are among several factors that contribute to the process complexity. The model developed by the authors (Ali and Rohani, 1995) is used lo investigate the effect of the three-lumped kinetic scheme (Weekman and Nace, 1970) and the four-lumped scheme (Lee ct ah, 1989) on the model predictability and reliability. The effect of changes in the catalyst circulation rate, gas oil feed rate, and oxygen feed concentration on various process variables is compared. It is shown that the three-lumped kinetic scheme, despite its extensive use in the literature (McFarlane et ah, 1993; Elnashaie and Elshishini, 1993; Theologos and Markatos, 1993; Arandes and de Lasa, 1992; Lopez-lsunza and Ruiz-Martinez, 1991), leads to erroneous results and should not be used in the dynamic simulation of the FCC units, 相似文献
144.
刘海渔 《徐州工程学院学报》2005,20(3):99-101
砂轮堵塞是影响砂轮耐用度的重要指标,磨削液在磨削加工中起到润滑、冷却、清洗等作用,对砂轮的堵塞有着较大影响.文章通过试验,分析了磨削液对砂轮堵塞的原因. 相似文献
145.
146.
M. van der Kraan M.V. Fernandez Cid G.F. Woerlee W.J.T. Veugelers C.J. Peters G.J. Witkamp 《The Journal of Supercritical Fluids》2007,40(3):336-343
When natural fibres are dyed in supercritical carbon dioxide, the addition of a small amount of water increases coloration. For a process design it is important to know how much water has to be added to obtain a desired humidity of both textile and carbon dioxide. In this work a thermodynamic model is proposed to calculate the distribution of water over the textile phase and the supercritical phase as a function of pressure and temperature. The phase equilibrium is described with Raoult's law for non-ideal fluids. The absorbed water in the textile is a condensed phase and is modelled here as a non-ideal liquid, using the NRTL-equation. The non-ideality of the supercritical phase is described by a solubility enhancement factor, a new equation derived from statistical thermodynamics. Although the model is applied to cotton, viscose, silk and wool, it can be used for all water absorbing textiles. 相似文献
147.
S. A. Mousavi Dehghani 《Petroleum Science and Technology》2007,25(11):1435-1446
Natural depletion of petroleum reservoirs as well as gas injection for enhance oil recovery, are unavoidable processes in the oil industry. Foremost, prediction of the problems due to these two processes is very necessary and important. So many field and experimental experiences have shown that heavy organic depositions, especially asphaltene deposition, are principal results during these processes. Results of laboratory simulation of asphaltene deposition during the natural depletion of petroleum reservoirs and also during gas injection and enhanced oil recovery (EOR) processes are reported here. This is achieved through the design of a new experimental setup for the investigation of pressure and composition effects on asphaltene deposition in petroleum fluids at high pressure and high temperature conditions. In this work, asphaltene deposition during decreasing pressure, from pressures greater than reservoir pressure to pressures below the bubble point pressure (natural depletion) and also asphaltene deposition during natural gas injection in reservoir conditions, are studied for three samples—one recombined sample and two bottomhole samples. All of the obtained results from this work conform to theoretical and other experimental works. 相似文献
148.
Jyh-Ping Hsu Shu-Chuan Yang Jung-Chieh Chen 《Journal of the Chinese Institute of Chemical Engineers》2007,38(5-6):409-418
The boundary effect and the presence of a nearby entity on the drag of a rigid entity is investigated by considering the movement of two identical, rigid, coaxial spheres normal to a plane in both a Newtonian and a Carreau fluid at a low to medium large Reynolds number. The parameters key to the phenomenon under consideration, including the nature of the fluid, the separation distance between two spheres, the distance between the near sphere and the plane, and the Reynolds number, on the drag coefficient are discussed. We show that the influence of a boundary on the drag coefficient is more important than that of the nature of a fluid and that of the separation distance between two spheres. The variation of the drag coefficient as a function of Reynolds number for a Carreau fluid is similar to that for a Newtonian fluid. Due to the shear-thinning nature of the former the drag coefficient in the former is smaller than that in the latter. The influence of the index parameter of a Carreau fluid becomes appreciable only if the Carreau number is sufficiently large. Correlations between the drag coefficient and the key parameters of a system are developed for the case when the Reynolds number is smaller than l. 相似文献
149.
A parallel implementation of the preconditioned GMRES method is described. The method is used to solve the discretized incompressible Navier–Stokes equations. A parallel implementation of the inner product is given, which appears to be scalable on a massively parallel computer. The most difficult part to parallelize is the ILU-preconditioner. We parallelize the preconditioner using ideas proposed by Bastian and Horton (P. Bastian, G. Horton, SIAM. J. Stat. Comput. 12 (1991) 1457–1470). Contrary to some other parallel methods, the required number of iterations is independent of the number of processors used. A model is presented to predict the efficiency of the method. Experiments are done on the Cray T3D, computing the solution of a two-dimensional incompressible flow. Predictions of computing time show good correspondence with measurements. 相似文献
150.