弯扭

The fatigue reliability analysis for the 16V240ZJB diesel engine crankshaft inserving DF4B internal-combustion locomotive were carried out in thisdissertation.Firstly,according to the fatigue loads of the crankshaft,the bendstress and torsion stress at danger zone in rated operation modes werecalculated respectively.The stress randomicity of the crankshaft was analyzedrelating operation modes of acceptance,and the probability distribution ofstresses were obtained with statistical analysis.

运用本文所提出的疲劳可靠性分析模型(干涉模型-Miner准则综合法及弯扭复合模型)和经分析简化得到的材料p-S-N曲线和p-Sa-Sm-N曲面，分别按一维、二维疲劳应力及弯扭复合应力三种情况对东风4B型内燃机车16V240ZJB柴油机曲轴进行了疲劳可靠性分析。

From crankle coupling point of view,circumvolving shafting vibration is studied so as to get the shafting dynamics characteristic more accurately thus promising the security of the shafting's running .

从弯扭耦合的角度来研究旋转轴系的振动，将能更准确地把握轴系的动力学特性，从而为轴系的安全运行提供更有效的保障。

It belongs the kind of complex bridges because its liner changes usually and the weight condition is also complex, except bear moment and shearing force, there are larger torsion and doubled moment, as a result, crankle、warping and aberration would happen.

这种异形桥梁结构是受力很复杂的一种桥型，其线性变化多端，结构受力复杂，除承受弯距、剪力外，还有较大扭矩和翘曲双力矩的作用，即使外荷载的作用通过梁的剪切中心，也将发生弯扭组合变形，同时伴随有截面的翘曲和畸变。

The wall has no support during the construction stage and the calculationbased on the national standard GB 50018-2002 (Technical code of cold-formedthin-wall steel, structures) should be reliable and safe. The crankle destabilizationof the studs with cold-formed channel section should be taken into account whencalculating the load-carrying capacity. The warpings at both ends of the sectionshould be calculated without any constraint when converting the crankledestabilization into the slenderness rationλ_w.

墙体在施工阶段基本为无墙体支撑，此时，按现行国标《冷弯薄壁型钢结构技术规程》(GB 50018-2002)规定计算是可靠、偏安全的，在计算其承载能力时应考虑单轴对称冷弯卷边槽钢截面立柱弯扭失稳，在计算立柱弯扭失稳换算长细比λ_w时，截面两端翘曲宜按不受到约束条件计算。

In response to distortional double coordination about deflection and torsion in the storied covery in which major and secondary beam s are used,utilizing the angle distortion displacement method and moment equilibrium distribution method of deflection and torsion yields the calculation formula of displacement.

针对主、次梁楼盖中正交梁系弯扭变形双协调问题，采用弯扭角变位移法与弯扭力矩综合平衡分配法，推导出杆端位移、弯矩及扭矩的计算公式。

A new idea is come up as"quasi-double-degree oscillation"to explain the actions of the upper and nether water rivulet on cable surface. And study of those oscillation by the equilibrium equation has established based on our new idea.

另外对拉索表面上下雨流的作用提出了拟弯扭双自由度驰振的思想，建立拟弯扭双自由度驰振的平衡方程并进行了分析。

The phase of ω0 frequency fluctuates tempestuously. The resonance peaks of flexural and torsional vibrations response are present at 2/3ω0 1/2ω0 1/3ω0 and 1/4ω0 with three kinds cracked rotor models. Near 1/2ω0 frequency, quasi-periodic and chaotic motions maybe appear. Periodic, quasi-periodic and chaotic motions show on alternately when the rotating speed is near to 2/3ω0.Combined step-by-step integral method with traditional transfer matrix method, an increment transfer matrix method is put forward.

研究结果表明：各种故障情况下，华北电力大学博士学位论文弯振和扭振之间都存在祸合关系，但弯扭祸合振动一般不会威胁机组安全运行：在叶片丢失或滑环飞脱故障时，将产生很大的弯振，同时各转子扭振也将被激发出来，它以工倍频和前三阶固有频率为主；在各种电气故障情况下，各转子都很快被激励出较大幅值的扭振来，相应各转子弯振也发生一定的变化，但它的变化明显滞后于扭振，扭振和扭矩主要以前三阶固有频率为主。

The responses properties of coupled vibrations for 120° and 180°asynchronous juxtaposition of 200MW turbine-generator set were analyzed. The results show that the responses properties of flexural and torsional vibrations caused by 120° asynchronous juxtaposition are similar to that of 180° asynchronous juxtaposition. When the fault happened, Former two steps inherence frequencies and whirl speed frequency of torsion are excited. And the first step inherence frequencies of flexural vibration are also excited besides whirl speed frequency. Transient electromagnetism moment peak, torsional and torsional moment responses caused by 180° asynchronous juxtaposition are lower than that of 120° asynchronous juxtaposition.

利用该方法，针对某200MW汽轮发电机组的120°和180°两种非同期并列情况，进行了机组弯扭耦合振动响应特性研究，分析表明：汽轮发电机组的120°和180°两种非同期并列情况下的弯振和扭振响应特性基本相似；非同期并列主要激发出工频和前两阶固有频率扭振，弯振除工频主分量外，第一阶固有频率也被激发出来；180°非同期并列时的暂态电磁力矩峰值比120°非同期并列时低，相应的扭振和扭矩响应也小于后者。

To give him breast-feeding or washing diapers always writhing; hold him again, he Camponotus弯身; actually say, 'these fixtures quickly and I lay down, I have other things to do.

给他喂奶或洗尿布时总是扭来扭去；抱他时他又弓背又弯身；实际上是说'快把我放下，我有别的事情要做。

Thus, for a precise and reliable design, the effect of the colling air mixing must be taken into consideration.

弯扭叶片是一种具有复杂几何形状的新型高效叶片，它的出现和应用给设计方法提出了更高的要求，因而必须建立适用于具有弯扭叶片的燃气涡轮的设计计算方法。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失