体积积分

This makes more and more people pay more attention to studies and applications of numerical simulation in thermal recovery. In this research, we have developed a reliable mathematical model for thermal recovery, which takes a full consideration of the effect of viscos, gravitical and capillary forces on the three-phase flow of gas, water and oil, the effect of the temperature on the medium characteristics of liquid and solid, the phase equilibrium of gas-liquid in each component, heat transportation including connection, conduction and radiation as well as heat losses in both the overburn and underlying strata. In the space discreation of the mathematical model, we have proposed a new method based on the improvement of the conventional nine-points difference approximation, which has a higher difference accurancy.

本项研究以热力采油的主要机理为基础，充分考虑在粘性力、重力和毛管力作用下油水气三相流动，考虑温度对各种流体和固体介质物性的影响，考虑每一组分中汽液两相的相平衡，考虑热在地层中的传导、对流和辐射以及上下盖层的热损失，利用热力学第一定律、质量守恒定律和流体迁移定律，建立了正确可靠的注蒸汽数学模型；在对数学模型进行空间离散时，利用控制有限体积积分法，对以往的九点差分近似作了合理的改进，使其具有较高的差分近似精度：结果表明，该公式的近似精度要比以往文献中所给的九点差分近似精度高，可以认为，在油藏数值模拟中，如果遇到非均质情况，使用这种九点差分近似更合理。

In this paper, starting from the double integral, double integral first introduced the basic concept and calculation method, the re - Top songs integral cylinder volume and surface area, for example in the application, as well as the double integral in the application of mechanics.

本文从二重积分入手，首先介绍了二重积分的基本概念和计算方法，二重积分计算曲顶柱体体积和曲面面积的在应用举例，以及二重积分在力学中的应用。

In the computation of aerodynamic forces, the present work is based on the work of Morino et al., but the following aspects are improved:(1) In computing the steady transonic aerodynamic load, the steady transonic nonlinear integral equation is solved by relaxation-iteration method in this thesis, instead of solving the time dependent transonic nonlinear integral equation, so that the computing time is saved greatly;(2) The influence coeifficients represented by volume integral are transformed to surface integral by using the Gaussian Theorem, so the analytical form of these coeifficients can be obtained and this leads to be more convenient to analyse and compile computer program;(3) The shock capturing method is used in every time step in present work, no shock moving term is added in the integral equation, so that it is more convenient and simpler to treat.

在气动力计算方面，本文基于Morino等人的工作，作了如下几方面的改进：（1）在计算定常跨音速流场（作为非定常绕流计算的初场）时，本文采用松驰迭代法直接求解跨音速定常非线性积分方程，而不是采用时间相关法求解非定常非线性积分方程，这样大大节省了计算机时；（2）将以体积分形式出现的影响系数化为面积分，并获得解析公式，这样便于分析和编写程序；（3）对运动的激波，本文通过在每一个时间步长上采用激波捕捉法而得到，而不是在积分方程中附加激波运动项，因而处理起来简单方便得多。

In this paper, applying an integral expression of linear viscoelastic theory, several integral equation expressions for obtaining shear modulus G from stress relaxation modulus E{t and bulk modulus K are acquired by using inversion of the Laplace Transform.

本文应用线粘弹性理论的一种粘弹性积分变换式，采用拉氏逆变换，导出了由拉伸松弛模量E和体积松弛模量K求解剪切模量G的几种积分方程，并给出了由已知试验数据E和K通过迭代和数值积分求G的数值积分算法。

Divergence Theorem: is a vector theorem that allows a surface integral of the normal component of the vector to be transfomed into a volume integral of the divergence of a vector, or vice versa.

散度定理：将矢量表面积分转换为体积积分的散度形式。

Then introduced a triple integral calculation of the basic concepts and methods of calculating the triple integral in three-dimensional volume, as well as the mechanical application of triple integral example .

随后介绍了三重积分的基本概念和计算方法，三重积分计算立体体积以及力学中三重积分的应用举例。

The term involving the time derivative of the control volume integral represents unsteady effects associated with the fact that values of the parameter within the control volume may change with time.

这条件包含了控制体积积分法内，与在控制容积中的参数可能会随时间改变这个事实所相关的非定常效应。

Starting from this dowble, firstly introduces the basic concept and the double integral method, double Integral calculation music volume and surface area of top cylinder, and the application examples in the double integral application in mechanics.

本文从二重积分入手，首先介绍了二重积分的基本概念和计算方法，二重积分计算曲顶柱体体积和曲面面积的在应用举例，以及二重积分在力学中的应用。

Using the divergence theorem, converted the area integral of the flux of stress for the surface force to a volume integral of the divergence of stress.

应用散度定理，将通量应力的面积积分转换成应力散度的体积积分。

Then used the divergence theorem to turn the area integrals into volume integrals.

然后利用散度定理将面积积分转换成体积积分。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。