数值计算

In this paper, the space-time finite element theory and its application technologies are studied and discussed. Furthermore the space-time finite element method is used to analyze the transient characteristics of electromagnetism equipments. The work is important to develop the numerical method for the transient electromagnetic field. The detailed work is as follow.In the basis theory of finite element method used in the transient engineering problem, the functional theory and the finite element theory are applied to studied the existence condition of a generalized variation principle, which is the basis of the space-time finite element method.

本文在完善时空有限元法的基础理论和应用技术并将该方法应用于解决电磁装置的瞬态过程分析等相关方面进行了深入的研究与探讨，该工作对于发展瞬变电磁场问题的数值计算方法具有重要的意义，为此进行了如下几方面的工作：在工程瞬变问题的有限元方法的基础理论方面，本文应用泛函理论和有限元理论，系统讨论了一般工程瞬变问题的变分定理的存在条件及对应的变分定理。

The numerical method of the variational principle combined with finite element method is presented in the paper.

文中介绍了运用该变分原理并结合有限元方法进行数值计算的方法。

In the fourth chapter, using the magnetic vector potential as the unknown variable, a mathematical model for numerical calculation of the magnetic field and loss distribution in 3-phase 5-limb transformer core is presented.

第三章针对变压器铁心结构的特点，对各向异性非线性边值问题的有限元分析方法进行了详细的阐述，并推导出了实用的N-R格式及单元分析格式，对具有多媒质单元的有限元分析方法进行了介绍，为变压器铁心磁场及损耗分布的数值计算奠定了基础。

Numerical study on the viscous flow and the hydrodynamic forces on a ship in turning motion in shallow water.

2浅水域船舶回转运动的粘性绕流场及水动力数值计算研究。

The author solved both unsteady and steady incompressible Navier-Stokes equations to simulate viscous flows and hydrodynamic force around a ship with free surface.

作者通过求解不可压缩Navier-Stokes方程数值计算水面船舶的粘性流场和水动力。

Lots of towing tank test data are used to prove the validity of the numerical simulation method in this paper to predict the viscous resistance of a submarine under water.

运用大量的拖曳水池阻力试验结果考察了本文采用的潜艇粘性流场数值计算方法预估水下阻力的有效性和可靠性。

At last, to use the method to calculate the warship, and evaluate the effect.

最后，将数值计算方法应用于某水面舰艇，对舰船进行兴波阻力评估。

The acoustic field of the pulse wave source is measured, the measuring value is in accordance with the calculating results on the whole.

对脉冲波声场的测试结果表明，数值计算和实测结果有较好的一致性。

The air pressure wave on the surface of train body in full-scale-test working state was calculated by numerical simulation computing, the frequency range of air pressure wave was estimated, and as a conclusion, the reasonable sampling frequency can be set in the range from 300 to 500 Hz.

通过分析实车测试工况下车体表面压力波的数值计算结果，估计被测空气压力波的频率范围，确定测试系统合理采样频率可设置为300~500Hz。

Based on existing theory of dielectric resonator, several difference configuration whispering gallery modes dielectric resonator and the characteristic of coupling between such a resonator and millimeter-wave transmission line are studied by means of electromagnetic theory, microwave theory and microwave circuit theory in this dissertation.

本文在现有的介质谐振器分析理论基础上，利用电磁场理论，微波理论和微波电路理论对几种不同的结构的边廊模介质谐振器和它与传输线间的耦合进行理论分析，并用数值计算的方法分析求解了这些边廊模介质谐振器的电磁参数和电路参数。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。