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稠油油藏CO_2吞吐合理吞吐轮次

大庆石油地质与开发 2017年第1期36卷 129-133页

作者：史英盖长城颜菲周微曾悠悠李彩莲中国石油冀东油田分公司河北唐山063004

冀东油田高浅北区稠油油藏高含水油井自2010年底实施CO_2吞吐控水增油以来,取得良好效果。但首轮吞吐失效后,面临吞吐增油量逐轮减少、换油率下降、吨油成本不断上升的问题。为了有效提高吞吐措施效果,在明确CO_2吞吐控水增油机理和主... 详细信息

冀东油田高浅北区稠油油藏高含水油井自2010年底实施CO_2吞吐控水增油以来,取得良好效果。但首轮吞吐失效后,面临吞吐增油量逐轮减少、换油率下降、吨油成本不断上升的问题。为了有效提高吞吐措施效果,在明确CO_2吞吐控水增油机理和主要注采参数优化的基础上,以高浅北区某典型底水稠油油藏为例,考虑不同构造位置、水平井轨迹差异及不同采出程度,进行CO_2吞吐合理吞吐轮次数值模拟研究。研究表明:多轮吞吐效果主要受构造位置、井轨迹及含油饱和度的影响,高部位物性好的油井实施5轮次吞吐效果较好;腰部采出程度相对较低的油井可实施4轮吞吐;采出程度相对较高的油井、边部中部位油井可实施3轮次吞吐。矿场实践证实,该方法可减少无效措施工作量,实现多轮吞吐经济效益最优化。

关键词：底水油藏稠油 CO2吞吐极限周期数值模拟冀东油田

EXISTENCE AND ANALYTICAL APPROXIMATIONS OF LIMIT CYCLES IN A THREE-DIMENSIONAL NONLINEAR AUTONOMOUS FEEDBACK CONTROL SYSTEM

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Journal of Systems Science & Complexity 2014年第6期27卷 1158-1171页

作者： CHEN Huaxiong SHEN Jianhe ZHOU Zheyan School of Mathematics and Computer Science Fujian Normal University

This paper is concerned with the existence and the analytical approximations of limit cycles in a three-dimensional nonlinear autonomous feedback control *** on three-dimensional Hopf bifurcation theorem,the existence of limit cycles is first *** the homotopy analysis method(HAM) is applied to obtain the analytical approximations of the limit cycle and its *** deriving the higher-order approximations,the authors utilized the idea of a perturbation procedure proposed for limit cycles' approximation in van der Pol *** comparing with the numerical integration solutions,it is shown that the accuracy of the analytical results obtained in this paper is very high,even when the amplitude of the limit cycle is large.

关键词：反馈控制系统三维非线性极限环自治逼近极限周期霍普夫分岔同伦分析

LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM (III)_(m=0) HAVING THREE ANTI-SADDLES (I)

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 167-174页

作者： YE YANQIAN Department of Mathematics, Nanjing University, Nanjing 210008, China. 南京大学数学系江苏南京

For the quadratic system:x=-y+δx+lx^2+ny^21y=x(1+ax-y)under condtions -10 the author draws in the (a,b)parameter plane the global bifurcation diagram of trajectories around O(0,0).Notice that when na^2+1<0 the system... 详细信息

关键词：极限周期分歧曲线二次微分系统反鞍点

Global Bifurcation of a Perturbed Double-Homoclinic Loop

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Chinese Annals of Mathematics,Series B 2006年第4期27卷 425-436页

作者： Desheng SHANG Maoan HAN School of Mathematics and Information Science Shandong University of Technology Zibo 255049 Shandong China. School of Mathematical Sciences Shanghai Normal University Shanghai 200234 China.

这篇论文与不安处理一种第四个度系统。由使用多参数不安理论的方法；质的分析，系统能让六限制周期，这被证明。

关键词：扰动分叉立方系统极限周期哈密顿系统数学分析

Small-amplitude limit cycles of polynomial Linard systems

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Science China Mathematics 2013年第8期56卷 1543-1556页

作者： HAN MaoAn TIAN Yun YU Pei Department of Mathematics Shanghai Normal University Department of Applied Mathematics The University of Western Ontario

In this paper,we study the number of limit cycles appeared in Hopf bifurcations of a Linard system with multiple *** an application to some polynomial Li'enard systems of the form x=y,y=gm(x)-fn(x)y,we obtain a new ... 详细信息

关键词： Liénard系统多项式极限环 Lienard系统幅度霍普夫分岔杜松子酒极限周期

Numerical Simulation of Heat Exchanger＇s Length＇s Effect in a Thermoacoustic Engine

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Journal of Physical Science and Application 2015年第1期5卷 61-65页

作者： Mohamed Zouhir Dar Ramdane Miloud Abidat Mohamed Hamel Institute of Maintenance and Industrial Security University of Oran BP1524 El M'Naouer Oran 31000 Algerie Applied Mechanics Laboratory USTO-MB BP 1505 Oran El M'Naouer Oran 31000 Algerie

A numerical study of a standing-wave thermoacoustic engine is presented. The aim of this work is to study the effect of increasing the heat exchangers length on the acoustic power. The analysis of the flow and the prediction of the heat transfer are performed by solving the non linear unsteady Navier-Stocks equations using the finite volume method implemented in -ANSYS CFX- CFD code. The results show an increase in the limit cycle acoustic pressure and power as well as the specific work per cycle with the increase of heat exchangers length.

关键词：热声发动机数值模拟长度换热器热交换器极限周期有限体积法预测分析