抽油机井环空测试仪器现场解卡方法

环空测试中仪器遇卡或缠绕油管是环空测试的一大阻力。经现场实践，总结出“下放仪器法”、“硬挤法”、“钩钢丝法”、“抬井口法”等4种解卡、解缠的方法，避免了仪器落井事故；另外，正确安装合格新式的偏心井口，也可以避免缠、卡的发生。     

Transient forced convection in the entrance region of porous concentric annuli

The problem of transient laminar forced convection in the entrance region of a porous concentric annulus with developing thermal boundary layer is solved numerically by the finite difference technique. The hydrodynamic behaviour of the flow is assumed to be steady and fully developed, and both Darcian and non-Darcian effects on the flow are considered.     

幂律流体在偏心环空中流动的Hanks稳定性参数

在水平井的钻井和固井作业中,井的环空是偏心环空,而偏心环空不同于圆管和同心环空,它是几何边界不规则的区域,从而给判定非牛顿流体在偏心环空中流动的稳定性带来了巨大的困难。利用幂律流体在偏心环空中流动的数值解,研究汉克斯(Hanks)稳定性参数,得到了如下重要规律:Hanks稳定性参数的最大值和最小值分别在偏心环空的最宽边和最窄边处,符合已有的实验观察结论;Hanks稳定性参数的最大值和最小值总是在靠近钻柱壁的位置处,即层流的失稳点总是从钻柱壁附近开始发生,然后发展到整个环空,这点对钻井和固井是极端不利的;偏心越严重,则在偏心环空的最宽边和最窄边处的最大Hanks稳定性参数相差越大,一般大于5~100倍,这充分地说明了偏心时最宽边处早已是紊流但是最窄边却仍然是层流,符合实验和工程实际情况。表明了汉克斯(Hanks)稳定性参数对水平井的钻井和固井作业中水力参数的科学设计具有重要应用价值。     

无机聚合物钻井液在冷43块的应用

辽河油田冷４３块因含大颗粒矽砾岩，地层成岩性差，胶结松散，过去采用聚合物不分散泥浆施工，馆陶组以上地层井径扩大严重，不规则，且易渗漏。采用触变性能好、剪切稀释性好、携屑能力强的无机聚合物钻井液，并与钻井工程相配合，优化井身结构设计，控制合理的排量（２９Ｌ／ｓ左右），保持较低环空返速（小于１ｍ／ｓ）以减少钻井液对井壁的冲刷作用，有效地防止了井径扩大、地层渗漏，提高了井身质量和固井质量。     

提高水平井钻井液携岩能力的实践及认识

通过分析岩屑携带和沉降规律，得出钻井液流变性是影响岩屑携带能力的首要因素。在室内实验和现场实践的基础上，指出生物聚合物是满足水平井钻井液需要的优良流变性调整剂，同时确定了钻井液流变参数控制原则。     

Effect of Newtonian heating/cooling on free convection in an annular permeable region in the presence of heat source/sink

The influence of Newtonian heating/cooling in the presence of heat source/sink has been investigated on laminar free convective flow in a vertical annular permeable region. The mathematical model for the problem has been considered as a boundary value problem consisting of two simultaneous ordinary differential equations. The boundary value problem has been transformed to nondimensional form. This has given rise to a number of parameters representing both geometrical and physical features of the problem. Closed‐form analytical solutions of the governing equations have been obtained for two different cases of internal heat generation/absorption. To assess the effects of governing parameters on the fluid velocity and temperature, a number of profiles of these field variables have been presented. The efficacy of the distinct processes on the field variables has been discussed extensively. The main outcome obtained in this study is that the velocity as well as temperature is enhanced in the case of the Newtonian heating while the opposite behavior occurs in the Newtonian cooling for both cases of source and sink. Furthermore, the influence of the governing parameters has been shown on the skin friction, volume flow rate, and the Nusselt number.     

Experimental investigation of multiphase flow behavior in drilling annuli using high speed visualization technique

Imaging with high definition video camera is an important technique to visualize the drilling conditions and to study the physics of complex multiphase flow associated with the hole cleaning process. The main advantage of visualizing multiphase flow in a drilling annulus is that the viewer can easily distinguish fluid phases, flow patterns and thicknesses of cutting beds. In this paper the hole cleaning process which involves the transportation of cuttings through a horizontal annulus was studied. The two-phase (solid-liquid) and the three-phase (solid-liquid-gas) flow conditions involved in this kind of annular transportation were experimentally simulated and images were taken using a high definition camera. Analyzing the captured images, a number of important parameters like velocities of different phases, heights of solid beds and sizes of gas bubbles were determined. Two different techniques based on an image analysis software and MATLAB coding were used for the determinations. The results were compared to validate the image analyzing methodology. The visualization technique developed in this paper has a direct application in investigating the critical conditions required for efficient hole cleaning as well as in optimizing the mud program during both planning and operational phases of drilling. Particularly, it would be useful in predicting the cuttings transport performance, estimating solid bed height, gas bubble size, and mean velocities of bubbles/particles.     

均质围岩灌浆锚杆应力的近似解析解

灌浆锚杆与岩体介质的耦合机理和支护效果的解析评估，目前尚处于研究进展阶段。本文对全长处于均质围岩塑性屈服区的弹性锚杆，按围岩弹-脆-塑性应力应变关系和Mohr-Coulomb屈服准则，给出了锚杆的应力、位移和介质交界面屈服长度的解析表达式。这一解析模型考虑了锚杆切应力 对围岩的剪切抑制作用。把它应用于Kielder试验洞，计算和实测结果吻合尚好。对Kielder洞探讨了加大杆长的效益，计算表明，加大杆长的效益并不显著，该洞采用1.8 m的杆长是合适的。所提出的解析模型可用于非轴对称地下洞室，是一个较简明的解答，有利于工程初步设计阶段的参数识别，支护荷载及其效果的评估。     

变传动比环面蜗杆滚销式曲柄传动

变传动比蜗杆曲柄销式传动机构，其环面蜗杆的齿距是依变传动比的函数关系变化的，当环面蜗杆匀速转动时，通过啮合使滚销式曲柄产生预期的变速转动，可应用于铸造生产的铁水浇包的倾转机构。这里依啮合原理给出了车削变齿距环面蜗杆的齿面方程和磨削的环面蜗杆齿面方程、一类及二类界限曲线。     

大型多支承回转窑调窑参数模糊优化

分析了大型多支承变截面回转窑的力学特征 ,以回转窑运行轴线偏差最小及各托轮受力均衡为优化目标 ,建立了调窑参数模糊优化模型 ,应用模糊集理论和方法获得了最优解。在中国长城铝业公司氧化铝厂 2 #窑的应用中表明 ,根据本文研究的调窑参数模糊优化结果进行调窑 ,显著提高了回转窑的运转率。