江苏油田G凹陷储层条件下岩石纵横波速度实验研究

为研究江苏油田G凹陷储层的岩石纵横波速度变化特性,采集了76块岩石样品,在实验室模拟地层温度、压力条件下干燥、饱水和饱油三种状态岩样的声波测量实验,分析了温度、压力、孔隙度和密度的变化对岩石纵横波速度的影响。结果表明,在干燥、饱水和饱油三种状态下,岩石纵横波速度呈现较好正线性相关性;压力对纵横波速度的影响大于温度的影响;岩石纵横波速度与孔隙度呈负线性相关性;岩石纵横波速度与密度呈较好幂指数关系。实验结果可以为该地区地震和测井资料反演和解释提供了重要的参考依据。     

温州半岛浅滩二期围涂工程促淤方案初步研究

随着高滩资源的日益减少,低滩资源的开发利用逐渐引起沿海各地政府和技术人员的重视。低滩围垦的关键问题是促淤方案的比优。以温州浅滩二期围涂工程为例,提出了筑坝促淤方案,并通过模型试验研究,验证了方案的可行性。     

Numerical analysis of hydrodynamic bearings with significant journal lateral velocities

The previously reported¹ numerical analysis method for hydrodynamic journal bearings has been extended to take account of significant lateral velocities of the journal. Conditions encountered in bearings with substantial dynamic loading have therefore been covered. This paper is intended to be used in conjunction with reference 1, and it is essentially a refinement of the method described therein. Results obtained by means of the numerical analysis method presented here are given in reference 2. The application of these results to journal orbit prediction, and comparison with experimental orbits is covered by reference 5, and an example is presented herein.     

基于滤膜淤积法的油液污染在线监测系统

针对油液污染是导致液压系统故障的主要原因以及目前国内外油液污染大多不能实现在线监测的现状,提出基于滤膜淤积法的恒功率测量法,在保证功率恒定的情况下测量通过某一固定体积时的压差来间接测量油液的污染度。采用阀用直流电磁铁作为主推动力元件来推动特制液压缸内活塞杆来获得压降,自制金属滤膜作为传感元件,并设计了监控软件操作平台,完成了油液污染在线监测系统的设计、调试和试验工作。试验结果表明,该系统能给出相应的ISO、NAS及SAE油液污染等级,并有良好的人机交互能力。与离线测试装置相比,具有可信的精确度和实时性,可满足生产现场的使用要求,具有一定的推广应用价值。     

ANALYSIS OF FLUID DYNAMICS IN A SPOUTED BED WITH CONTINUOUS SOLIDS FEEDING

ABSTRACT

An experimental study was carried out on Quid dynamics and solids movement in a modified spouted bed with the feeding of particles through the base, at different air rates, panicle feed rates and bed heights. Moreover, a model was adapted for the base-feed configuration, and results of its numerical resolution were compared with experimental data. Analysis showed that the modeling of the bed is complex due to a lack of knowledge of fundamental spout parameters, such as the fluid-particle drag coefficient. Air velocities in the spout were predicted by the model with a maximum deviation of 15%, whereas prediction of particle velocities in the spout yielded maximum deviations of 50%.     

Spouting characteristics of spf wood pellets

The spouting characteristics with ambient air of cylindrical wood pellets, 6.5 mm in diameter and 11.1 ± 4.1 mm long, were investigated using a transparent 152.4‐mm diameter semi‐circular cone‐based cylindrical column. Despite the previously unexplored shape of the pellets in the spouted bed mode, the measured minimum spouting velocities at different bed heights, the maximum spoutable bed height and the mean spout diameter above the conical base were all well represented by equations from the literature developed mainly for more rounded particles. Pellet attrition was found to be severe, so that the possible torrefaction of the pellets by the spouting technique without sacrifice of their integrity appears to be unlikely. © 2012 Canadian Society for Chemical Engineering     

A Fuzzy Logic Model for Predicting Dipole Shear Sonic Imager Parameters From Conventional Well Logs

Sonic wave velocities, including compressional, shear, and Stoneley, are functional and practical parameters for various branches of reservoir characterization. In the last few years, several tools such as the dipole shear sonic imager (DSI) were introduced for measuring sonic wave velocities. Most of these instruments are expensive and drilling companies do not run them in all wells of a field because of economical restrictions. In this study, an accurate, intelligent, and indirect method was presented for prediction of sonic wave velocities, which are directly obtained from dipole shear sonic log, utilizing conventional well log data and fuzzy logic technique. Furthermore, the proposed methodology was applied on a carbonate reservoir of Iran. The results of the case study demonstrated the capabilities of fuzzy logic for estimation of sonic wave velocities, where DSI may not be run. The MSEs of the predicted V_p, V_s , and V_st in the test data calculated 1.47 (US/F), 4.96 (US/F), and 2.219 (US/F), respectively, which correspond to the R ² values of 91.8%, 89.3%, and 90.4%, respectively.     

Elastic properties and sound velocities of silicane/graphane hybrids

Using ab initio density functional theory, the effect of hydrogen arrangement on the elastic properties of silicene–graphene hybrid is studied. Mechanical stability, elastic constants and sound velocities of pure and five configurations of hydrogenated SiC sheet, namely, chair, table, boat, zigzag and armchair, are explicitly examined. To reveal the anisotropic properties of the six structures, the polar plots of Young’s modulus, Poisson ratio and acoustic waves speed are given. Compared to graphene, it is shown that all the isotropic systems are less stiffer with lower in-plane Young’s modulus and stronger with their larger Poisson ratio, moreover, their compressional and shear waves propagate faster. The analysis of linear elastic behavior shows that the armchair configuration has an auxetic structure. The result of this work could be used for the design of future silicane–graphane based nanodevices with potentially large technological impact in nanomechanics.     

Anomalous friction in slurry flows

Experiments conducted with water slurries of 1 mm particles of specific gravity 1.59 in a laboratory pipeline 0.105 m in diameter have provided evidence of a change in the friction mechanism at velocities above 3 m/s. These flows were stratified and at low velocities the frictional pressure gradients were in satisfactory agreement with the predictions of the conventional two‐layer model. However at higher velocities the friction is substantially lower than predicted. Measurements of concentration and velocity distributions within the pipe show that no major change in flow regime occurs concurrently with the change in the friction mechanism. It appears that the effect is due to a change in the nature of the particle‐wall interaction, of a type which suggests that an inward‐acting force affects the particles adjacent to the wall.     

平面二维悬沙数学模型计算河口闸下淤积的缺陷及弥补方法

分析了感潮河段闸下淤积机理及用平面二维悬沙数学模型模拟闸下淤积存在的缺陷．提出采用分析模式预测近闸段的泥沙平均淤厚，其余河段由平面二维悬沙数学模型预测淤积分布相结合的方法．实例分析表明，该方法可为河口建闸可行性研究提供依据．