模拟

MD are analog sensors, the digitizing happens when the electrons are passed through the analog to digital converter. The A to D converter converts the analog signal to a digital file or signal.

CD 属于模拟传感器，当电子从模拟转换传输到数字转换器时实现数字化。A/D转换器将模拟信号转换到数字文件或信号。

Computer simulation of fire is an important research area.

火焰模拟是自然景物模拟的一个重要研究内容，现有的火焰模拟算法分为两大类，直接数字合成与视觉效果建模。

The fire is always the significant disaster, The study is making a strong fire combustion chamber and make use of PLC（Programmable Logic-Controller）to control need of air and fuel gas. It do simulate test of fire in advance actual situation. And it monitored thermograph inside fire combustion chamber, compare whit fire thermal current analyze by computer. It result can understand about discrepancy between actual and simulate fire. So, the study build fire simulator can train fire fighter and appraise cause of fire, and the data of discrepancy between actual and simulate fire can take as references of fire situation.

火灾是最频繁的重大灾害，本研究建立一个实体坚固的燃烧室，运用逻辑可程式控制器，控制燃烧所需要的空气量、瓦斯量等，在预先设定的情境下，进行实际火场的模拟测试，另在火场的温度监测下，可与电脑模拟热流场分析做比对，以了解火场实际与模拟差异性；因此，除开发火灾模拟器之外，亦可推广作为火场救灾训练及火灾事故原因鉴定，另热流场分析比对数据，也可作为火场情境之研究参考使用。

In chapter 1, the history of numerical simulation of extinguish fire is introduced. The technique and theory of fire suppression by water mist are presented, and the sort of numerical simulation of extinguish fire is discussed.

第一章回顾了细水雾灭火过程数值模拟的发展历程，介绍了细水雾灭火技术和灭火机理，同时阐述了火灾数值模拟的分类，以及国内外在灭火数值模拟方面的研发现状。

Using the a hand-hold GPS and wireless transmitting unit to rapidly locate the fire and determine the rate of fire spread, which also offered an indispensable way of verifying the speed of forest fire appealing. Discussing the representation and Computing Method of the simulate calculation error based on the thorough investigation of the sources of simulate calculation error. Pointing out that the speed and directional error are the root of forest fire appealing simulates error. Thus increasing the parameter of error correction is an effect way of reducing systematicsimulationerrors.

4提出了一种利用手持GPS和无线传输设备来快速测定火场位置和林火实际蔓延速度的方法，为林火蔓延模拟速度验证提供了必要的手段；对林火蔓延模拟误差的来源进行了全面分析，探讨了林火蔓延误差的表现形式和计算方法，指出了林火蔓延速度误差和蔓延方向误差是林火蔓延误差产生的根源，提出了通过增加系统误差修正参数来减少系统模拟误差的有效方法。

Springback character of rubber forming was studied by numerical method and springback compensation of rib flanging was analyzed.

基于数值模拟方法模拟了橡皮成形过程的回弹规律，对翼肋零件的翻边回弹进行了数值模拟，并通过试验进行了比较。

This thesis systematically reviewed the development of research methods of domestic and foreign float glass tank, and using Computational Fluid Dynamics software Fluent established mathematical model of glass flow and heat transfer model in the float glass tank.

本文在前人关于浮法玻璃熔窑数学模拟研究的基础上，利用计算流体力学模拟软件Fluent建立了浮法玻璃熔窑内玻璃液传热与流动模型的数学模型，适当利用简化处理方式对浮法玻璃熔窑内玻璃液流场和温度场进行数值模拟。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory.

本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory. The key techniques used in numerical simulation of the three-dimensional extrusion from dies such as decision of boundary conditions, creation of initial velocity field, selection of penalty factor, high Weissenberg number problem , regeneration of the free surface were studied in detail.

中文题名聚合物异型材口模挤出三维流动研究副题名外文题名 Study on three-dimensional flow of polymer melts during the process of profile extrusion from dies 论文作者涂志刚导师柳和生包忠诩教授学科专业材料加工工程研究领域\研究方向学位级别博士学位授予单位南昌大学学位授予日期2001 论文页码总数148页关键词挤出成型聚合物材料挤出口模聚合物异型材馆藏号BSLW /2003 /TQ320 /9 本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

A comprehensive review and expectation about researching status in quo and development trends of viscous flow numerical simulation technique are given in this paper and grids generation methods, numerical computation methods, turbulent model and moving boundary simulation methods are the emphasis study in the paper. On the basic of above job a mathematical model of simulation turbulent flow with free surface is established and triumphantly applied to numerical computation on 2D spillway and 3D spillway with frusta of brake.

本文针对粘流场数值模拟技术的研究现状和发展动态作了比较全面的回顾与展望，重点研究了网格生成技术、数值求解技术、湍流模型技术和动边界模拟技术，在此基础上建立了模拟自由面湍流场的数学模型，并成功地应用到二维溢流坝和带闸墩的三维溢流坝过坝水流的数值计算。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。