特性态

The thesis can be divided into five parts as follows: First, the structural characteristics of finned-pipe evaporator are analyzed. After selecting suitable microelement controller, the heat-transfer and mass-transfer processes are analyzed for every microelement under the conditions of dryness, wetness and frostiness. Based on previous equations, some parameters of frostiness are confirmed and the frost-growing model is set up under frost condition. Some hypotheses are postulated and with the help of the equation of mass-conservation, energy-conservation and momentum-conservation, the evaporation model which fits in the dynamic simulation is built, which set a solid foundation for system simulation. Second, the starting and stopping behaviors under disturbed condition are analyzed and calculated by using the dynamic concentrative parameter model, which gives some advice to better prescribe refrigeration system and set theoretic foundation for carrying out automatic control of refrigeration system. Third, the normal running process is analyzed and calculated by means of rational matching theory, which gives some advice on how to better understand the parameter change under steady state and the affection of inlet-parameter on evaporator. Fourth, the simulation software with dynamic characteristic is designed, which can be applied to calculate thernio-parameter of cryogen, air humidity and frost thickness under different initial and boundary conditions, and to carry out dynamic simulation under conditions of dryness, wetness and frostiness, at the same time, to achieve detection and simulation at any stage from starting to stopping.

本文的主要内容如下：1对翅片管蒸发器结构特点进行分析，选取适当的微元控制体，就干、湿和霜工况下对每个微元分别进行传热传质分析，基于经验关系式确定霜的有关参数，对于霜工况下的霜生长建立模型，经适当假设，运用质量守恒、能量守恒和动量守恒方程建立适合动态仿真的蒸发器数学模型，为系统仿真奠定基础； 2对蒸发在大扰动下的开、停机过程，运用动态集中参数模型进行分析和计算，为更好地描述制冷系统运行的全过程奠定基础，同时也为制冷系统实现自动控制提供一定的理论基础； 3对蒸发器正常运行过程，运用动态分布参数和参数间定量耦合的观点来分析和计算，为更好地了解稳态工况下各点参数的变化情况及各入口参数对蒸发器动态特性的影响即蒸发器性能对各参数变化的敏感性； 4编写翅片管蒸发器动态特性仿真计算程序，可以计算不同边界条件和初始条件下的制冷剂热力参数、空气温湿度和霜厚度分布场，实现对翅片管蒸发器在干、湿和霜工况下的动态仿真。

From the characteristics of aerothermoelasticity, the effects of temperature in aerodynamic heating on the mode of a delta wing and the characteristic of its flutter were researched.

根据热气动弹性特点，探讨了气动加热温度对三角机翼模态特性和颤振特性的影响。

Based on modeling and simulation of the steady characteristic of five-phase hybrid stepping motor driver system with fixed-chopping frequency, constant total current driving and new pentagon winding connection pattern, the paper studies the dynamic characteristic of the system, especially single step response characteristic.

本文在建立绕组接法采用新五边形接法，驱动方式采用恒频斩波恒总流驱动时的五相混合式步进电动机系统的稳态仿真模型的基础上，分析研究了其动态特性，并重点对单步响应特性进行了研究与分析。

The static and dynamic characteristics of brushless DC generator and the effects of main generator circuit on exciter circuit are analyzed.

分析了无刷直流发电机的稳态及动态特性，以及主发电机整流电路对励磁电路工作特性的影响。

A novel scheme that improves SOA dynamic performance via increasing properly the facet reflectivity of device is proposed, and is validated in theory by the high-speed dynamic model. Simulation results show evidently that this scheme is superior to other schemes in the efficiency of dynamic characteristic improvement, steady-state gain, output ratio and external condition requirements.

提出了通过适当增加SOA端面反射率来改善SOA动态特性的新方案，并利用SOA高速动态响应模型进行了理论验证，模拟结果证实了该方案改善SOA动态特性的有效性以及在稳态增益、输出信号消光比和对外部泵浦条件的苛刻程度方面相对其他方案的优势。

It design an overloading protection equipments base on the characteristic of the Super High-speed rotating equipment ,which are fit for a certain super high-speed rotating equipment,,and analysing the mechanical characteristic of the super high-speed rotating part by the finite element method.

针对超高速旋转设备的工作特点，设计了适合超高速旋转设备使用的过载保护装置，并利用有限元方法分析了超高速旋转条件下的转子力学特性；对包括模态、冲击响应、谐响应等在内的过载保护器动态特性以及工作过程中产生的不平衡量和摩擦热等影响过载保护装置正常工作的因素进行了分析计算。

Based on the hydraulic model test of Pudong north road pumping station in Shanghai, the hydraulic characteristics of the forebay were studied in the conditions of no diversion, the set-up of water-depressed plate and the set-ups of water-depressed plate and guide piers . Also, the hydraulic characteristic of the siphon outlet piping was studied.

本文结合上海市浦东北路泵站水力模型试验研究课题，从城市排污泵站布置的特点出发，研究和分析了前池在改善流态无工程措施情况下、设置压水板措施和设置导流墩和压水板组合措施情况下前池的水力特性；虹吸式出水管在虹吸形成过程和虹吸破坏过程的水力特性。

At first, the characteristics of probability distribution and frequency spectrum of noise inside measuring signal of feedback elements are discussed. Statistic filter method is come up with for noise signal of being Gauss distribution. It is analyzed reason that statistic filter method is superior to arithmetic average filter method.

分析了反馈元件测量信号中噪声的概率分布特性和频谱特性，对呈正态分布的噪声信号提出了统计滤波法，分析了该滤波法优于算术平均滤波法的原因。

The fatigue life followed the logarithmic normal distribution or the two-parameter Weibull distribution by the probability regression method.

为研究预腐蚀对疲劳寿命的影响，进行30CrMnS iN i2A和LC4CS试件加速预腐蚀不同时间后的成组随机谱下的疲劳试验，采用概率回归方法对预腐蚀疲劳寿命分布特性进行检验，表明可采用对数正态分布和双参数威布尔分布描述疲劳寿命分布特性。

The output-input properties of the measurement system, power amplifier and active magnetic actuator when the linear, hamonic and rotating control signal respectly acts on, is investigated and measured.

在转子轴承实验台上，以实验的方法研究了转子振动主动控制系统各环节的输入输出特性以及电磁执行器在线性输入、谐波输入和旋转控制信号作用下的稳态响应特性。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。