COMPSS软件利用靶点坐标反算井口坐标并设计轨道

利用COMPSS强大的计算作图能力,通过靶点坐标反算井口坐标,并设计轨道参数,可以掌握定向井水平井的设计主动权,根据需要调整靶点坐标,降低轨道设计和实钻控制难度,实现超前设计。     

基于两步矩阵投影的数据分类算法

提出了一种数据分类的两步矩阵投影算法.指出Crowe提出的矩阵投影算法在数据分类中存在由于投影矩阵不惟一,导致已测可校正数据分类不彻底的缺点.采用已测数据预分类的方法,对其进行了修正.在此基础上,将矩阵投影算法引入到了未测数据分类中,提出了基于矩阵投影算法的未测数据分类算法.新算法只需求解两个投影矩阵就可以实现所有数据分类.从而避免了常规方法在未测数据分类时,求解未测数据关联矩阵绝对线性无关列的计算,提高了计算效率.数学推导和算例验证了新算法的有效性.     

中美规范钢筋砼构件配筋比较

为比较钢筋砼构件采用中美规范设计计算结果,首先取相同的材料按各自的取值方法、试验方法换算出各自的材料指标,分析比较两本规范在设计参数取值上的不同,推导出中国常用的钢筋和砼按美国规范取值强度指标的换算公式,计算出中国常用钢筋和砼等级按美国规范取值的的强度指标。再通过两本规范的基本假定、荷载组合和设计表达式,推导出矩形截面梁的纵筋、箍筋以及大偏压柱纵筋计算公式,分析比较两本规范在设计方法的区别,最后通过计算实例比较两本规范梁、柱配筋计算结果的差异。     

带蒙皮FRP格栅-混凝土组合板设计方法及工程算例

采用一种新型的带蒙皮FRP格栅,在其上浇筑混凝土制备桥面板。采用换算截面法推导了带蒙皮FRP格栅-混凝土组合板截面在使用阶段的截面有效抗弯刚度,并通过材料力学的方法推导了板件跨中挠度的计算公式。依据相关规范进行带蒙皮FRP格栅-混凝土组合桥面板的设计并给出设计实例及计算方法。验算结果表明,带蒙皮FRP格栅-混凝土桥面板应用于混凝土-复合材料组合桥梁结构较为可行。     

计算发煙硫酸—硫酸混合物浓度的算图

发烟硫酸——硫酸混合物的浓度如果先算出各个成分之全SO_3浓度再进行计算则显得简单。此时可以计算混合物的全SO_3量,需要时亦可将它换算成硫酸或％发烟硫酸。 工业上,由于硫酸的浓度以％H_2SO_4表示,而发烟硫酸的浓度则以％游离SO_3表示,所以计算复杂。算图1简化了将这些参数换算成全SO_3的步骤。     

定向井数据校正方法研究

通过探讨定向井对井位、井深、厚度的影响,研究一套定向并砂体深度、厚度、坐标校正计算方法,解决由此带来的对微幅度构造、油层连通状况及地质储量计算精度的影响,提高了定向井在测井解释、地质图幅绘制、地质储量计算以及储层剩余油描述等方面的应用精度.     

定向井钻井空间圆弧轨道计算的两个问题

定向井钻井空间圆弧是定向井钻井作业中比较典型的一种井眼轨道模型,对其实际应用中的计算问题进行研究分析,有利于提高定向井钻井作业中空间圆弧轨道的计算效率和水平,对于保证定向井钻井作业的准确性有着积极作用和意义。本文将结合定向井钻井空间圆弧轨道计算设计的实际情况,对其计算中的任意点井斜角与方位角以及通过井底参数实现定常井眼曲率模型预测等问题进行分析研究。     

三元系统代数配料法的改进

本文通过数学推导得出结论，三元系统代数配料计算法，可以直接采用各个原料已知化学成分分析值进行原料配合比的计算，而不需要将成分分析值换算成灼后成分值，传统方法具备简化条件，据此，提出了改进方法－简式计算法，它比原来的计算方法有计算环节少，计算误差小的优点。     

动态法热重分析（TG）推算硫化胶热寿命的方法

用换算时间的计算方法对石墨—硅橡胶复合体热重曲线(TG)进行动力学分析,用Doyle和Zsako′积分公式及Sharp和Wentworth扩展法微分公式,从一条热分析曲线推导出反应机理,算出活化能△E,频率因子A等动力学参数,计算寿命—温度关系。求得温度指数(寿命为20000h的最高使用温度)为229℃,在250℃下寿命为2820h。由算出的△E,A进行热分析曲线反算,以验证所得结果的正确性。     

水平管道气液两相段塞流参数计算的精确模型

分析了水平管内气液两相段塞流的运动特性和形态特征以及段塞单元内部的速度分布规律,建立了水平管路气液两相段塞单元的物理模型。将一个完整的段塞流单元分为液相段塞区和液层/气泡区,建立了液相段塞区的质量和动量守恒方程,计算了其压降和持液率;对液层区,模型考虑液层厚度分布不均(坡状液层)对参数计算的影响,通过建立局部控制方程,推导了液层高度随流动方向坐标变化的表达式,并将持液率和湿周写成液层高度的函数。通过与实验和其他模型的计算结果对比,本文建立的模型可以对压降和持液率有更准确的预测结果。     

离心泵叶轮叶片的加工方法研究

此篇论文主要写了叶轮直纹叶片在DMU-70eV的五轴数控铣中的加工方法。首先介绍了叶片的造型方法，通过木模截线图和轴面投影图获取型值点进行三维造型；然后根据叶片成型原理来进行刀路规划，让工作台旋转至合适角度，使刀具能够沿轴面截线方向走刀；接着详述了刀距和刀具加工起始点坐标的计算方法，通过B样条曲线插值方法来求新的型值点坐标；最后编写刀路，并进行加工模拟仿真。     

液化烃球罐固定式水喷雾系统计算方法的探讨

在球罐固定式消防冷却水系统的设计时,如果以喷头水雾锥保护球罐表面弧长来计算环管层数,可以很方便地计算出结果。喷头的布置大都提出采用菱形或矩形布置,实际在球面上实现菱形或矩形布置是比较困难的。在系统压力计算方面,如水雾喷头采用一个固定工作压力计算,则计算出的用水量和工作压力会出现偏差,这样消防水泵、供水管道和消防水储备量的选择都会出现偏差,因此提出消防冷却水系统计算应逐点逐段地进行计算。在水雾喷头的布置方面,应控制喷头水雾锥沿纬线方向相交、沿经线方向相接为宜。     

Zuordnung von Schwingungsspektren organischer Moleküle durch MNDO-Berechnungen

Assignment of the Vibrational Spectra of Organic Molecules by MNDO Calculations Wavenumbers and intensities of the molecular vibrations can be calculated by the semi-empirical SCF-MO method, MNDO. The calculated normal coordinates show the displacements of the atoms in the course of the vibration and provide the assignment of mode and symmetry of the vibrations. This will be shown for the following examples: acetylene, ethylene, substituted and deuterated ethylenes, acetonitrile as well as for EDA complexes. We found a good qualitative agreement between calculated and experimentally observed IR-data.     

异形聚酯纤维束芯吸效应的分析

通过建立纤维束单元模型,采用自行开发的纤维束截面数学模拟软件,模拟了圆形、方形、三角形和双十字形4种不同截面的异形聚酯纤维束内毛细空隙当量半径值的大小和分布状态,计算了液体在纤维束内的统计流量。双十字形截面的纤维束当量半径值多分布在较小的区域内,有利于液体爬升,当量半径累计值和统计流量大于其他3种纤维束,具有较好的芯吸效应。     

Estimation of the resin flow permeability of fiber tow preforms using the self-consistent method

This paper presents a model using the self-consistent method for estimating the resin flow permeability of fiber tow preforms. The permeable resin is assumed to be a Newtonian fluid, such as an uncured and low viscosity epoxy resin. Permeability in both longitudinal and transverse directions is considered. In the discussion, a basic cell insertion is constructed to include a representative fiber tow surrounded with fluid. The insertion is placed into a homogeneous medium with an unknown permeability. Stokes flow is applied to the fluid region, and Darcy flow is considered at the tow region and in the outside homogeneous medium. Boundary and interface conditions as well as consistent conditions, including the total amount of the flow and the dissipation energy, are applied accordingly. Permeability is solved from these considerations. The prediction expresions using parameters of average fiber volume fraction, tow volume fraction, and tow size are derived. The results show that the main flow paths are the openings or gaps between neighboring tows in both longitudinal and transverse directions. The observation provides a scientific base for the simplification of the problem treatment.     

Analysis of SiC/SiC composites for energy applications at ambient conditions

Plain weave planar and biaxially braided tubular SiC/SiC CMCs are evaluated in tension and four-point bending, respectively, at ambient conditions. Custom-designed fixtures for CMC testing are developed for each loading mode and are coupled with three-dimensional digital image correlation. Stereoscopic image correlation analysis reveals crack initiation and failure sites to provide insight into stress redistribution mechanisms. Scanning electron microscopy is performed postmortem to determine the influence of microstructural features on crack initiation and failure. Crack spacing is measured in situ by stereoscopic image correlation and confirmed by SEM measurements to relate to underlying tow-tow crossing points. Triangulated surface heights of plain weave tow architecture are used to determine that subtle differences in neighboring transverse tow angle, which vary within a range of ±4° from horizontal, have no significant effect on final fracture location. The results presented reaffirm the state of current SiC/SiC CMCs developed for energy applications and will help to further improve SiC/SiC and other CMCs.     

Simulation of phase diagrams of oxychromites with a spinel structure

Phase diagrams of oxychromites with a spinel structure are described in the context of the Landau phenomenological theory of phase transitions. As an approximation of the thermodynamic potential of the sixth degree with respect to components of the order parameter, the implementation conditions of each type of phase diagrams are found. Equations for calculation of coordinates of tricritical and triple points are obtained. A qualitative agreement of the theoretically calculated results of the phase diagrams and experimental phase diagrams of some oxychromites with a spinel structure is observed.     

Performance evaluation of a solar still by using the concept of solar fractionation

In this communication an attempt has been made to find out distribution of solar radiation, using the concept of solar fraction inside a conventional (single slope) solar still by using AUTOCAD 2000 for a given solar azimuth and altitude angle and latitude, longitude of the place. Further the experimental validation of the model developed earlier has been carried out for design and climatic parameters. Numerical computations have been carried out for New Delhi climatic conditions (latitude 28°35′ N, longitude 77°12′E). It has been observed that for given parameters, solar fraction can play a very important role at a lower value of the solar altitude angle.     

BUCK-BOOST变换器的输出能量分析及电感电容优化设计

从最小点燃曲线角度分析BUCK-BOOST变换器内部本质安全性能,推算出BUCK-BOOST最恶劣情况下的能量,与火花点燃曲线相比较,得到本安输出的BUCK-BOOST变换器,并通过计算得出最大负载电容及负载电感。     

A stochastic analysis of contaminant transport through a rough-surfaced fracture

A stochastic model for the calculation of flow and contaminant transport in a single fracture with variable apertures was presented. The spatially varying apertures of the fracture were generated using a geostatistical method, based on a given aperture probability density distribution and a specified spatial correlation length. Fluid flowed between two points in the fracture plane. The fluid potential at each node of the discretization mesh was computed and the steady state flow rates between all the nodes were obtained. Then the contaminant transport was calculated using a particle tracking method. The migration plumes of contaminant between the inlet and the outlet were displayed in contour plots and contaminant elution profiles were also plotted. Calculations showed that fluid flow occured predominantly in a few preferred paths. Hence, the large range of apertures in the fracture gives rise to flow channeling. Simulation results were correlated with the basic input parameters: standard deviation of a lognormal aperture distribution function and the spatial correlation length.