大庆F区块挥发性油藏流体特征及影响因素分析

运用气相色谱法对分离油和分离气进行了组成组分及原油物性分析。利用PVTsim得到F区块地层油组成组分,通过模拟多次脱气实验,研究了该区块原油的高压物性参数变化及影响其变化的因素,分析了分离级数及开采条件变化对流体组成及物性的影响。结果表明,该区块地层油具有轻烃(C1~C6)含量高、密度低、收缩性强、溶解气油体积比大的特点;与黑油相比,压力变化对PVT参数的影响更大;油藏流体PVT特征对分离级数具有强烈的敏感性,多级分离时,地层油收缩率较小,脱气量较小,产油量较大;小油嘴开采时,嘴前压力较高,原油中轻质组分脱气相对较少,采出的原油中轻质组分较高,轻质组分更容易被开采出来。     

DSP56F805和CAN总线在交流伺服系统中的应用与研究

介绍了一种面向电机控制的数字信号处理芯片DSP56F805,采用现场总线控制系统的设计思想, 设计并实现了一个基于以太网和CAN 总线的多电机的伺服控制系统.首先采用DSP56F805 来控制单个永磁同步伺服电机的运行,从而构成FCS(现场总线控制系统) 中的一个智能节点.然后利用CAN 总线把这些智能节点连接起来,构成一个含有多个永磁同步电机(PMSM)子控制系统的FCS,最后利用以太网构成远程控制系统.该系统通过PVT(位置-速度-时间)插值算法对运动曲线进行平滑处理以及运用离散PIP算法对运动过程加以控制.所设计的系统不但便于对多电机进行集中的监测和管理,而且可以实现系统中的各个PMSM间的相互通讯而达到协调工作的目的.实验结果表明,该系统控制精度高、响应速度快、低速运行平稳,同时还具有连接简单、系统可靠和易于实现等优点.     

IC芯片粘片机并联焊头机构的插补算法及误差分析

针对所设计的IC芯片粘片机的并联焊头机构,对其在平面上任意曲线的插补算法进行了分析.利用驱动轴的PVT插补规律和对分式原则对并联焊头机构运动轨迹的插补误差进行了计算,并通过Matlab软件进行了仿真.结果表明, 轨迹的插补误差与插补直线的斜率、所分的段数和焊头机构的位置有关.     

改进SAFT方程用于链状分子流体PVT性质的计算

采用Ｃｈｉｅｗ的硬球链方程描述分子间的排斥作用,改进了ＳＡＦＴ状态化学方程。对烷烃、芳香烃、酮、卤代烃和聚合物体系ＰＶＴ性质的计算结果表明,改进后的ＳＡＦＴ状态方程进一步提高计算精度,初值的敏感性降低,模型参数呈良好的规律性,为提高模型对聚合物溶液相平衡预测能力奠定了良好的基础。     

凝析气藏相态参数实验研究

油气藏流体主要有烃类成分组成,在油藏及地面条件下,这种烃类混合物的物理性质取决于其化学成分及给定的温度和压力。对于烃类的相态特征及流体组分研究在油气田开发中具有重要的意义,尤其是凝析气藏田。对海榆和10井的研究,归纳总结其流体PVT性质,为其开发提供科学依据。     

凝析气藏油气水三相PVT相态特征测试及分析

常规凝析油气体系PVT相态测试方法忽略了气态凝析水对凝析油气体系相态的影响,而国内外凝析气藏开发实践表明,气态凝析水对凝析油气体系相态特征的影响不应被忽略.为了更有效地指导凝析气藏的开发,必须建立考虑气态凝析水的凝析油气体系PVT相态测试和计算方法.探索设计了富含气态凝析水的凝析油气体系PVT相态测试方法,并与常规凝析油-气两相平衡体系的PVT测试结果进行了对比,分析了考虑气态水组分的存在对凝析油气体系相态的影响.     

Dew point pressure model for gas condensate reservoirs based on multi-gene genetic programming approach

One of the most critical parameters in characterization of gas condensate reservoirs is dew point pressure (DPP), and its accurate determination is a challenging task in development and management of these reservoirs. Experimental measurement of DPP is a costly and time consuming method. Therefore, searching for a quick, reliable, inexpensive, and robust algorithm for determination of DPP is of great importance. In this paper, first, a new approach based on multi-gene genetic programming (MGGP) to determine DPP of gas condensate reservoirs is presented. Then, a correlation for DPP calculation using MGGP has been developed for gas condensate reservoirs. Finally, the efficiency of the proposed DPP model has been validated by comparing its predictions with the results of other conventional models. It is found that the correlation developed in this work is capable of predicting more accurate values of DPP, with the lowest average relative and absolute errors with respect to the experimental results, and also higher correlation coefficient among the results of all the evaluated DPP correlations. Therefore, it is suggested that the proposed model can be applied effectively for DPP prediction for a wide range of gas properties and reservoir temperatures.     

New sinusoidal oscillator configurations using operational transresistance amplifier

The objective of this brief is to introduce four new structures of electronically tunable sinusoidal oscillators (SOs) designed using operational transresistance amplifier (OTRA). Each of the proposed SO consists of forward path derived from a generic structure along with one/two OTRA-based resistive gain stages or differentiator in its feedback path. All the proposed SOs enjoy independent tuning of the frequency of oscillation (FO) through resistors without affecting the condition of oscillation (CO). Further, all topologies are found to exhibit low f_o sensitivities at all frequencies with respect to circuit parameters, and the second topology is capable of achieving very low frequencies (VLFs) using less RC component spread and provides linear tuning too. The fourth circuit provides quadrature output. The proposed SOs have been successfully implemented and verified in 180-nm CMOS technology node using ADE (analog design environment) tool Cadence Virtuoso. Both prelayout and postlayout simulation results have been included. To assess the oscillator prefabrication performances, Monte Carlo and process-voltage-temperature (PVT) analyses have been performed. The total harmonic distortion (THD) is observed to be less than 3.5%.     

A Robust and Power-Effcient SoC Implementation in 65nm

Godson2H is a complex SoC (System-on-Chip) of Godson series, which is a 117mm2, 152 million transistors chip fabricated in 65nm CMOS LP/GP process technology. It integrates a 1GHz processor core and abundant high or low speed peripheral IO interfaces. To overcome on-chip-variation problems in deep submicron designs, many methods are adopted in clock tree, and PVT detectors are integrated for debug. To meet the low power constraints in different applications, most of state-of-the-art low power methods are used carefully, such as dynamic voltage and frequency scaling, power gating and aggressive multi-voltage design.     

基于电缆地层测试的储层产能预测方法研究

通过对电缆地层压力测试资料和采集流体样品的PVT组分分析,提出了电缆地层测试储层产能预测的方法,为部分替代DST测试提供了理论基础。首先,利用曲线拟合方法精确求取地层有效渗透率和表皮系数等产能参数;利用采集流体样品的PVT组分分析,确定原油黏度、体积系数和溶解气油比等流体参数,结合电缆地层测试的产能方程,从而计算出储层的采油指数(PI)或单层日产量。