查询词典 simulation

3D-CTM (Coupled Thermo-Mechanical Forming Simulation) software for precision forging process of aero-engine blade was developed. The key technologies of 3D coupled rigid-viscoplastic thermo-mechanical FEM simulation of blade forging process were studied systematically. By using the remeshing method of contracting from the boundary to the inner, new mesh system from old distorted mesh system can be obtained. A method of modifying the position of nodes touching on the die according to its original normal was proposed to avoid "dead lock" problem due to uncontinuity of normal of scatted die meshes. The pseudo-static iterative algorithm was used to simplify the coupled thermo-mechanical computation. In particular, formulations to determine relaxation factor β was established for rigid viscoplastic FEM adopting penalty function method, and an improved cubic factor rapid algorithm derived from these formulations was proposed by combining with the advantage of advance and retreat search method.

采用基于边界构形的内缩法，实现了三维畸变网格的重新划分；提出了初矢修正法对触模节点的位置进行修正，解决了由于离散的模具网格的法矢不连续造成的&死锁&问题；采用准静态迭代法简化了速度场和温度场耦合计算过程；特别是针对减速因子β的选取，建立了适用于三维复杂成形过程刚粘塑性罚函数法有限元三次因子法的计算公式，并结合进退搜索法提出了改进的三次因子快速算法，提高了模拟计算效率和稳定性，在此基础之上，开发了面向叶片精锻过程的三维刚粘塑性热力耦合有限元模拟分析系统(3D-CTM)，系统的可靠性得到了圆柱体镦粗的验证。

The method of CFD numerical simulation is employed to replace experimental investigation. Hence, STAR-CD of the commercial software is used to simulate the outer flow field and heat transfer performance of integrated heat sink with heat pipes cooled by airflow. It is found that simulated results agree with experimental results well, which indicates that simulation method is reasonable and reliable. Further, simulated computations for different fin thickness, fin pitches and air velocities are performed to analyze their effects on heat transfer performance of heat sink. Finally, a new optimized structure of integrated heat sink with heat pipes is provided to meet future demands for cooling CPU and its heat transfer is also evaluated. For multi-heat source and higher dissipation power of electronic devices, the integrated heat sink with heat pipes attatched fins stagged in different positions of channels is presented and its flow and temperature fields are also simulated to enhance heat transfer. As a conclusion, all mentioned above are useful for the design of heat sink with excellent efficiency of heat dissipation and further research.

应用商业软件Star-CD对CPU集成热管散热器的外部流场和传热特性进行了数值模拟，将数值模拟结果和试验结果对比，验证了所提出的数值计算方法是可靠和可行的；利用此数值模拟方法对CPU集成热管散热器在不同散热翅片间距、厚度和气流速度下散热器的流动与传热性能进行了数值计算，分析了这些参数的变化对散热器传热性能的影响；针对未来CPU冷却的要求，确定了与最优气体流速匹配的最佳翅片间距、厚度的CPU集成热管散热器的新结构；利用试验评测了根据数值模拟提供的新结构开发出的新CPU集成热管散热器的传热性能；最后在场协同强化传热的理论的基础上，对CPU集成热管散热器的散热翅片错位排列来强化散热器的散热，满足未来大功率、多热源的电子元件的散热，为今后进一步优化散热器提供了依据。

The methods to solve the harmonic superposing problem and their shortcomings are discussed. An electromagnetic transient simulation model is proposed to analyze multi-harmonic superposition and simulation experiment is made in this article.

文章系统地比较了当前多谐波源叠加方法的缺陷和局限性，并给出了运用数字仿真技术来进行多谐波源网络的谐波分析方法，进行了仿真实验。

The porous media model of software FLUENT was introduced to simulate the 2D flow through permeable tetrahedrons,and an experiment was conducted to verify the simulation;With the simulation,the influence of parameters such as Re、relative width b/B and relative length l/B on the protected length downstream of permeable tetrahedrons was studied.

本文首次尝试利用Fluent软件的介质模型对经过四面体透水框架群的水流进行了平面二维数值模拟，通过模型验证，多孔介质模型能较好地用于四面体透水框架群模拟；另外，通过数值计算，研究了Re、相对宽度b/B、相对长度l/B对四面体透水框架群下游保护长度的影响。

After several reductions of absorptions of capacitances and transconductances tunned can enter the very precise range with the error rate very low for the simulation resonance frequency.Finally, The above thesis was verified by TSMC 0.35u H-Spice simulation and improve the non-ideal effect for filter circuit with OTA-C at a high-frequency.

主要方法为计算出寄生电容值大小，来适当调整外加电容值，当调整至外加电容值近似於寄生电容值时，此时将外加电容移除，并搭配OTA转导值的调整，可让此电路在高频无外加电容时有更精准的输出。

The composition, function and characteristic of uncapping system are described, and the critical parts of the system are analyzed and calculated by using finite element method. The related action process of the spread of ring-like pressure mine girder and the motion of sail mine is analyzed with simulation interference. Theoretical calculation and simulation interference analysis show that the system can solve four actual problems and meet operational requirement.

介绍了环形压雷梁开盖系统的组成、功能和特征，深入分析了系统作用载荷，着重对系统的特征关键件进行了有限元分析与计算，并对环形压雷梁展开与航行雷运动的关联动作过程进行了详细的仿真干涉分析，理论分析及仿真结果表明，采用本技术能够解决4个方面的实际问题，满足使用要求。

Complex process simulation requests not only upbuilding accurate mathematical models of every mechanical and controlling link, but also the flexible combination, easy manipulation,strong expansion of the simulation platform.

复杂过程的仿真要对过程的各个机械或控制环节建立精确的数学模型，还要求仿真平台灵活组合、操作简捷、扩展性好。

The simulation and dynamic simulation experiment verifies the validity and feasibility of the method.

仿真和动模试验验证了该方法的有效性和可行性。

Finally, the numerical simulation approach of tool wear was studid on the basis of numerical simulation of SPIF, and the process parameters on the impact of the tool wear were researched.

最后，在渐进成形数值分析的基础上，探讨了对工具头磨损进行数值模拟分析的方法和流程，并通过仿真，研究了工艺参数对工具磨损的影响关系。

The objectives of this paper were to investigate the simulation and design of continuous multiple-station rolling forming process for a U-Section Steel Bar by CAE software-DEFORMTM Due to the limitation of elements number using a short strip 120mm went through all the stations to simulate the real continuous rolling forming on factory The roller gap was fixed as 0 30mm roll speed was 20 rad/sec and progressive angles were all equal for each rolling process which were the formed angle divided by by the number of station Three rolling processes were selected with 6 9 and 12 stations respectively During simulation processes two cases occurred Case A the strip was through a single station Case B the strip across two stations Because the strip laterals side was stretched and twisted during the process The model of case B closer to the practical process than case A and the calculated stress and strain on the tip of U section for case A were lower than these for case B by up to 15% From the result of case B for each process the stress for 12-station process was smallest 9-station process second and 6-station process next Because less-station can save larger cost and forming time but the bigger stress and strain for 6-station caused wrinkles on lateral sides not found on 9-station and 12-station Therefore 9-station process was a more suitable design than 12-station process smaller stretched and twisted and stress The progressive angles for 12-station was 7 5?

本文主要是以DEFORMTM有限元素软体模拟U型钢片连续道次成型与单一道次成型以确认单一道次模拟的是否可取代连续道次模拟之研究。因DEFORMTM 软体对於网格元素上的限制故使用较短素材120mm通过所有的成型站以模拟工厂实际连续成形方法。辊轮间隙固定为0 3mm；辊轮转速为20 rad/sec；弯曲角度的方法为将成型角度平均除以成型站数。有三种辊轮成型方式被选择分别为6站，9站，与12站。在模拟的过程中有两种现象会产生 Case A，素材通过单一成型站。Case B，素材会通过两个成型站。因为在模拟过程中素材的两端会有拉应力与扭力。Case B的模拟比Case A像实际的制程，并计算应力与应变在U型断面的Tip部中可发现Case A比Case B低约15%。从Case B的每站的结果可以得知，12站的成型应力最小，9站次之，6站最后。

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％。