求帮忙翻译外文文献语句通顺就ok1 used a 3-D FiniteDifference model to calculate the temperature. The circular bead section was modeled as a steppedCartesian grid. The shadowing effect (attenuation of the laser power at the workpiece due

求帮忙翻译外文文献语句通顺就ok1 used a 3-D FiniteDifference model to calculate the temperature. The circular bead section was modeled as a steppedCartesian grid. The shadowing effect (attenuation of the laser power at the workpiece due
求帮忙翻译外文文献语句通顺就ok
1 used a 3-D Finite
Difference model to calculate the temperature. The circular bead section was modeled as a stepped
Cartesian grid. The shadowing effect (attenuation of the laser power at the workpiece due to the
gas-powder jet) was considered. Clad dimensions were computed as a function of process
parameters, both for single and also for multiple track cases.
Kar and Mazumder
2-4 and Agrawal et al.
5 solved analytically the one-dimensional heat and
mass transfer (coupled) equations, for binary systems. The goal was to calculate the composition
of the extended solid solution that is formed by rapid cooling. Parametric studies were also
included, correlating variables such as laser power, beam radius, traverse speed, clad thickness
and film composition, and portions of several non-equilibrium phase diagrams were proposed.
Hoadley and Rappaz
6 used a 2-D Finite Element Model for the calculation of the quasi-
steady state temperature field. An idealized problem, in which almost no melting occurs in the
substrate, was taken as the basis for defining a successful cladding operation. Mixing was
assumed to distribute the powder instantaneously in the melt, which results in a volumetric heat
source term associated with the latent heat. The free surface is considered to be an arc of a circle
and the temperature of the powder particles is estimated. The calculation procedure involves
determination of the laser beam position that is consistent with the requirements of the idealized
problem. A parametric study involving laser power, processing speed and clad thickness was
included.
Picasso and Hoadley
7 used the Finite Element Method to solve for the stationary heat
transfer and fluid flow problem on a 2-D geometry. The model considers the deformation of the
gas-liquid interface and the forces associated with the powder injection into the melt pool, and the
powder is assumed to melt instantaneously as it hits the liquid surface. Picasso et al.
8 used an
iterative procedure, based on a 3-D analytical model for temperature, for obtaining process
parameters such as scanning speed and powder feed rate as a function of laser power, beam radius,
powder jet geometry and clad height. The shadowing effect and the dependence of the absorption
coefficient on the angle of incidence of laser radiation into the melt pool were also considered.
1.3 Proposed approach
The heat conduction equation and deformation mechanics equations are to be solved in a
two-dimensional domain, the longitudinal mid-plane of a clad track. It should be noted that this is a
rather drastic approximation, as the process is clearly three-dimensional (for instance, the height of
clad track is of the same order of magnitude of its half-width). Nevertheless, even a simple finite
element model should provide the correct trends for the effect of processing parameters on
temperature and stress fields.

求帮忙翻译外文文献语句通顺就ok1 used a 3-D FiniteDifference model to calculate the temperature. The circular bead section was modeled as a steppedCartesian grid. The shadowing effect (attenuation of the laser power at the workpiece due
1使用了三维有限 要计算温度的区别模型. 圆小珠部分被塑造了作为一个跨步的解析的栅格. 屏蔽效应(激光力量的衰减在制件的由于气体粉末喷气机)被考虑了. 作为过程功能,穿的维度被计算了 参量的唯一并且的多个轨道盒. Kar和Mazumder 2-4和Agrawal等. 5分析解决了一维热和 质量传递(被结合)等式,二进制的. 目标是计算由迅速冷却形成延长的固定解决方案的构成. 参数研究也包括,关联的可变物例如激光力量,射线半径、横速度、穿的厚度和影片构成,并且几张不平衡相位图的部分提议. Hoadley和Rappaz 6为演算类似使用了第2个有限要素模型 稳定温度领域. 一个被理想化的问题,几乎熔化在基体不发生,被采取了作为为定义成功的金属操作的依据. 混合是 假设分布粉末瞬间地在融解,导致一个容量热源期限联合以潜热. 自由表面认为圈子的弧,并且粉末微粒的温度估计. 演算做法介入与被理想化的问题的要求是一致的激光位置的决心. 介入激光力量、处理速度和穿的厚度的一项参数研究是 包括. 毕加索和Hoadley 7使用有限元法为固定式热解决 在第2几何的调动和流体流动问题. 模型考虑气液的接口和力量的变形与粉末射入相关入融解水池,并且粉末假设瞬间地熔化,当它击中液体表面. 毕加索等. 8使用了 重复做法,根据温度的三维分析模型,得到的过程参数例如扫描速度和粉末作为激光力量、射线半径、粉末喷气机几何和穿的高度功能的供给率. 屏蔽效应和吸收系数的依赖性对入射角激光辐射的到融解水池里也被考虑了. 1.3提出的方法 热量传导等式和变形机械工等式将解决在a 二维领域,一条穿的轨道的纵向盆腔中段平面. 值得注意的是,这是相当猛烈略计,因为过程明显地是三维(例如,高度穿的轨道是同一个数量级它的半宽). 然而,甚而一个简单的有限要素模型应该为过程参数的作用提供正确趋向 温度和应力场.