Question

机械专业英语翻译成中文（急）

软件直接托的不要，要人工的。辛苦大家了。谢谢！
3.3.1 Exact Solutions vs. Limit Analysis

Exact analytical solutions are not available for such problems in metal forming as flow through
conical converging dies. Approximations and simplifying assumptions are inevitable and many
approaches - slug equilibrium, slip line techniques and others - have been partially successful.
With recent advances in computer science and technology, numerical approaches are emerging
lately.

Limit analysis, as an analytical tool, is a promising approach which is being used with
increasing frequency. In this approach, as applied to the study of drawing or extrusion force, two
approximate solutions are developed. One, the upper-bound solution, provides a value which is
known to be higher than or equal to the actual force; the other, the lower-bound solution,
provides a value which is known to be equal to or lower than the actual force; the actual force
thus lies between the two solutions. For example, in Fig. <7>, with drawing stress as ordinate
and the semi-cone angle of the die as abscissa, upper- and lower-bound solutions are plotted for
several reductions together with corresponding measured values of actual stress. Even when
experimental results are not available, it is expected that the actual stress and the exact solution, if
these were available, would lie between the upper and lower bounds as obtained analytically.
Thus, by limit analysis, an approximate solution is given with an estimate of the maximum
possible error. The gap between upper- and lower-bound solutions may be narrowed by
providing several upper bounds, choosing the lowest upper bound, and by providing several
lower bounds, choosing the highest lower bound. Upper- and lower-bound solutions are obtained
by following strict rules (including requirement of proper description of friction behavior and
material characteristics) which thereby make the solutions upper and lower bounds. In Fig. <7>,
the upper bound is from Ref. [4] and the lower bound from Ref. [5]. The experimental data are
from Reference [6]. A full illustration of limit analysis is given in Section {9.5}, 'Limit
Analysis'.

The rules and procedures for developing an upper-bound solution will be demonstrated in
what follows, keeping in mind that several upper-bound solutions may be obtained for any
specific process.

Answer 1

3.3.1 Exact Solutions vs. Limit Analysis
3.3.1 精确解和极限分析
Exact analytical solutions are not available for such problems in metal forming as flow through
conical converging dies. 当通过圆锥会聚模流动时，金属成型中的这类问题不能获得精确的解析解。Approximations and simplifying assumptions are inevitable and many
approaches - slug equilibrium, slip line techniques and others - have been partially successful. 近似和简化假设不可避免，而很多途径已获得部分成功，比如段塞平衡（slug equilibrium）、滑移线技术等。
With recent advances in computer science and technology, numerical approaches are emerging
lately. 随着计算机科学和技术的最近进展，数值方法近来正在涌现。
Limit analysis, as an analytical tool, is a promising approach which is being used with
increasing frequency. 作为一种分析工具，极限分析是一种很有前途的方法，它正在越来越多的被采用。In this approach, as applied to the study of drawing or extrusion force, two
approximate solutions are developed. 在这种方法中，当用于拉丝力或挤压力的研究时，开发了两个近似解。 One, the upper-bound solution, provides a value which is known to be higher than or eq slip line techniques ual to the actual force; 一个是上限解，它提供了一个已知高于或等于实际力的值（这里原文有错，翻译不一定确切，请稍加修改）；the other, the lower-bound solution,
provides a value which is known to be equal to or lower than the actual force; 另一个是下限解，它提供了一个已知等于或低于实际力的值；the actual force thus lies between the two solutions. 因此实际力位于两个解之间。 For example, in Fig. <7>, with drawing stress as ordinate and the semi-cone angle of the die as abscissa, upper- and lower-bound solutions are plotted for several reductions together with corresponding measured values of actual stress. 例如，在图7中，在拉丝应力作为纵坐标，而模具的半锥角作为横坐标的情况下，在若干缩小量及相应的实际应力实测值时的上限解和下限解，它们被绘制成了曲线图。 Even when experimental results are not available, it is expected that the actual stress and the exact solution, if these were available, would lie between the upper and lower bounds as obtained analytically. 即使在不能获得实验结果时，预计实际应力和精确解，如果它们可以获得的话，也会如解析方法得到的那样，位于上下限之间。Thus, by limit analysis, an approximate solution is given with an estimate of the maximum possible error. 因此，通过极限分析，可在估计最大误差的情况下得到一个近似解。The gap between upper- and lower-bound solutions may be narrowed by providing several upper bounds, choosing the lowest upper bound, and by providing several lower bounds, choosing the highest lower bound. 上限解和下限解之间的间隔可以 通过提供若干上边界，选择最高的下边界来收窄。Upper- and lower-bound solutions are obtained by following strict rules (including requirement of proper description of friction behavior and material characteristics) which thereby make the solutions upper and lower bounds. 上限解和下限解遵循严格的规则获得（包括要求完善的描述磨擦性状和材料特性），从而使解处于上下边界间。In Fig. <7>, the upper bound is from Ref. [4] and the lower bound from Ref. [5]. 在图7中，上边界来自于文献【4】，下边界来自于文献【5】。The experimental data are from Reference [6]. 实验数据来自于文献【6】。A full illustration of limit analysis is given in Section {9.5}, 'Limit Analysis'.
对极限分析的充分说明在9.5节“极限分析”中提供。
The rules and procedures for developing an upper-bound solution will be demonstrated in
what follows, keeping in mind that several upper-bound solutions may be obtained for any
specific process. 用于开发上限解要遵循的规则和程序将加以演示，记住，对任何特定的工艺可能获得若干的上限解。

Answer 2

3.3.1确切的解答对极限分析

Exact分析解答为这样问题不是可利用的在形成的金属象流经
conical聚合的模子。 略计和简化假定是不可避免的和许多
approaches -猛击平衡，滑动线技术和其他-是部分地成功的。 在计算机科学和技术的With最近前进，数字方法是涌现的
lately.

Limit分析，作为一个分析工具，是使用与的一项可行措施increasing频率。 在这种方法，应用于图画或挤压力量的研究，二
approximate解答被开发。 一，上部跳起解答，提供是的价值是的known大于或等于实际力量; 其他，低跳起解答，
provides低于实际力量知道相等或的价值; 实际力量
thus放在二种解答之间。 例如，在图，与图画重音当弹道高度
and模子的半锥体角度作为横坐标的，上部和低跳起解答为被密谋与实际重音一起的对应的测量值的several减少。 既使当
experimental结果不是可利用的，期望实际重音和确切的解答，如果
these是可利用的，放在上限和下限之间如分析获得。
Thus，由极限分析，一种近似解答给与最大的估计possible错误。 鞋帮之间的空白和低跳起解答也许变窄
providing几个最高界面，选择最低的最高界面，和通过提供几
lower跳起，选择最高的最低界面。 上部和低跳起解答是获得的
by从事严密的规则(摩擦行为和的适当的描述的包括要求material特征)哪些从而使解答上限和下限。 在图，
the最高界面是从参考[4]和从参考[5的]最低界面。 实验性数据是
from参考[6]。 极限分析的一个充分的例证在{第9.5部分}被给， ‘极限
Analysis'.
开发的The规则和方法在上部跳起解答将被展示what跟随，记住几上部跳起解答可以为所有获得specific过程。

Answer 3

3.3.1苛求解答对极限分析

Exact分析解答为这样问题不是可利用的在形成的金属象流经
conical聚合的模子。 略计和简化假定是不可避免的和许多
approaches -猛击平衡，滑动线技术和其他-是部分地成功的。 在计算机科学和技术的With最近前进，数字方法是涌现的
lately.

Limit分析，作为一个分析工具，是使用与的一项可行措施increasing频率。 在这种方法，应用于图画或挤压力量的研究，二
approximate解答被开发。 一，上部跳起解答，提供是的价值是的known大于或等于实际力量; 其他，低跳起解答，
provides低于实际力量知道相等或的价值; 实际力量
thus放在二种解答之间。 例如，在图，与图画重音当弹道高度
and模子的半锥体角度作为横坐标的，上部和低跳起解答为被密谋与实际重音一起的对应的测量值的several减少。 既使当
experimental结果不是可利用的，期望实际重音和确切的解答，如果
these是可利用的，放在上限和下限之间如分析获得。
Thus，由极限分析，一种近似解答给与最大的估计possible错误。 鞋帮之间的空白和低跳起解答也许变窄
providing几个最高界面，选择最低的最高界面，和通过提供几
lower跳起，选择最高的最低界面。 上部和低跳起解答是获得的
by从事严密的规则(摩擦行为和的适当的描述的包括要求material特征)哪些从而使解答上限和下限。 在图，
the最高界面是从参考[4]和从参考[5的]最低界面。 实验性数据是
from参考[6]。 极限分析的一个充分的例证在{第9.5部分}被给， ‘极限
Analysis'.
开发的The规则和方法在上部跳起解答将被展示what跟随，记住几上部跳起解答可以为所有获得specific过程。

Answer 4

精确解和误差分析