LWS400卧螺离心机参数变化对转鼓强度和刚度的影响

采用Solid Works软件建立LWS400卧螺离心机转鼓几何模型并导入ANSYS Workbench软件中进行有限元分析。分别改变转鼓转速、转鼓壁厚和液池深度三个参数并讨论由此对转鼓强度和刚度的影响,以便为后续的优化设计方案提供参考。讨论结果表明:转鼓转速的提高或壁厚的减小都对转鼓强度和刚度有明显的影响,液池深度的变化对转鼓强度和刚度的影响不大。     

行星回转小圆筒连续加压过滤机的卸料机构分析

PDF过滤机在多轴行星运动机构上安装多个圆筒形过滤转鼓,每个转鼓在自转一公转复合运动下进行独立的过滤分离操作,机器中心部位安装固定的刮刀,用于刮除转鼓上的滤饼。复合运动的转鼓与刮刀配合构成复杂的卸料机构,其分析和设计是PDF过滤机的关键技术之一。笔者对该卸料机构进行了运动几何分析,将行星运动参数、刮刀安装结构参数、滤饼参数与卸料效率关联起来建立计算理论模型,为卸料机构设计和PDF过滤机的操作优化提供理论依据。     

离心机转鼓壁厚的影响因素及参数关系图

离心机转鼓壁厚的计算中,通过影响壁厚各因素大小变化的分析,找出各影响因素变化,对转鼓壁厚影响的程度和关系,并用图线对这些关系进行表述,即参数关系当量图表示,从而通过图线清楚地了解各因素对壁厚的影响情况,以确定适当的转鼓壁厚。     

离心机转鼓结构优化设计方法的研究

提出了一种基于有限元分析的离心机转鼓结构优化设计的新方法。通过ANSYS中的参数化建模模块建立了GKH1250虹吸离心机转鼓的计算模型,并在此基础上使用优化设计功能对其进行第一次优化计算,然后根据其优化结果对转鼓进行了刚度和强度分析,并对优化变量的限制条件作相应的调整,最后再通过有限元分析进行了第二次优化设计,实现了总质量最小的优化目标。为应用ANSYS优化设计功能进行离心机转鼓的优化设计提供了一种新的方法。     

全消光涤纶切片增黏工艺研究

以国望高科全消光涤纶切片为原料,通过切片质量、增黏升温工艺、转鼓真空度、转鼓转速、油泵压力及转鼓料位等工艺因素,对全消光涤纶切片转鼓增粘工艺进行研究.     

工程机械轮胎TKPH室内机床测试方法探讨

对工程机械轮胎TKPH值测试中测温孔深度和位置、速度及转鼓直径进行试验研究。结果表明:测温孔深至带束层时温度最高;胎冠中心测温孔宜选取在花纹块几何中心,但胎肩部位存在不确定性;不同系列轮胎测试选取速度不同;转鼓直径越大,TKPH值越高。     

三级活塞推料离心机数值模拟与操作参数优化

针对新型三级活塞推料离心机的研发,在转鼓尺寸和物料增大情况下,操作参数对分离过程中转鼓内侵蚀现象和分离效率有重要影响。采用样机实验结合CFD数值模拟,对三级活塞推料离心机进行三维建模和仿真,并利用密集离散粒子模型(DDPM)模拟侵蚀过程。基于粒度分析可知,氯化钠颗粒粒径dm为0.070~0.200 mm时,随颗粒粒径增加,固相对离心机转鼓内部的侵蚀越大。结合响应面分析法可知,响应模型各因素的交互影响明显,以更高分离率与更低侵蚀率作为评价指标,得出最优值为推料频率40次/min、转鼓转速1431 r/min、进料浓度60%。与实验数据进行对比,模拟结果的误差在可接受范围内。     

基于Euler多相流模型的卧螺离心机速度场数值模拟与分析

应用计算流体力学软件Fluent,基于Euler多相流模型,在多重参考系坐标下,选用RNG k-ε湍流模型,对卧螺离心机内部的三维速度场进行了数值模拟和分析。结果表明：当液体进入转鼓后,对沉降分离起主要作用的周向速度迅速增大,经过较短的距离即可获得稳定的流动状态,且沿转鼓轴向变化较小;轴向速度沿径向的梯度在转鼓柱段较小,而在锥段较大,且在靠近转鼓的区域,锥段的轴向速度比柱段的大;径向速度复杂多变,无明显规律,流动受几何结构的影响很大。     

虹吸式离心机转鼓结构的三维有限元安全分析

针对二维有限元分析对虹吸式离心机转鼓开孔对结构强度影响分析的不足,利用ANSYS有限元软件,采用参数建模的方法建立了三维GKH1250虹吸式离心机转鼓的实体模型,并将其离散化建立计算模型,进行了应力分析和刚度分析,同时,重点考察了过滤转鼓到虹吸室的滤液孔对转鼓结构强度的影响,得到其应力和变形云图,验证了该虹吸式离心机的设计符合刚度和强度的要求,也满足运转安全的要求。通过提供的建模和计算方法可对离心机转鼓设计提供参考。     

气孔结构对表面破碎强度及抗拉强度的影响

正高炉用焦的强度管理通常采用转鼓试验DI_(15)~(150)和转鼓试验TI4006等冷态转鼓强度指数,以煤化度及流动度等煤性状为参数直接预测焦炭强度,而有的研究是通过焦炭的结构和特性等预测焦炭强度。焦炭冷态强度除受基质强度影响外,还受微小龟裂和气孔结构的影响。转鼓强度DI_(15)~(150)的粉化分为表面破碎和体积破碎,引起焦炭表面破碎的原因是非黏结粒界和连接气孔,气孔率和气孔大小对焦炭冷态     

玻璃钢离心机转鼓的研制(Ⅱ)——玻璃钢设计理论及离心机转鼓强度设计

介绍了玻璃钢用于制作离心机转鼓的特点 ,讨论了所用强度理论、原材料选择、转鼓的三层式结构 ,并通过实例进行了计算 ,得出了一些结论     

采用过盈装配双筒离心机转鼓的强度计算

提出一种新型离心机转鼓结构及其设计计算方法。推导了采用过盈配合热压工艺装配的双筒离心机转鼓结构应力和位移的计算公式 ,并通过一离心机转鼓强度计算实例来说明其优越性     

离心机转鼓整体三维有限元分析与强度计算

转鼓是离心机的关键部件,其设计正朝着转速更高,直径更大的方向发展,因此鼓壁鼓底等零部件间的相互影响和作用越来越大。这类结构的强度问题更为突出,对强度分析的要求也越来越高。为此,本文提出用三维立体单元对过滤式离心机整个转鼓进行分析。由于此方法对转鼓全部采用三维立体单元进行网格划分,因而可以模拟复杂的局部结构和边界条件。本文对某国产卧式刮刀卸料离心机大直径转鼓的有限元计算结果表明,在转鼓底和拦液板中的应力水平较低;在转筒体中应力水平较高,在开孔周围存在着应力集中现象,最大虚拟弹性应力值远大于材料的屈服限。最后,对该离心机转进行了强度评定     

Combustion of lignite carbon under agitation

To get insights into the burning of large coal particles as agitated beds in the recently developed rotary chambers, combustion behaviour of eight Turkish lignites was studied in a laboratory-size rotating wire mesh basket. Single particles from 0.5 to 5 g average weight were loaded in the basket, which was then inserted into a preheated tube furnace. The net effect of removing ash continuously as a result of agitation on the combustion rates and times was searched for all the lignites, whereas the other parameters, such as rotation speed of the basket, particle size, temperature and air velocity, were investigated on only Çan lignite. Because both volatile and char combustion times and their confident prediction have important bearings in the design and capacity of coal combustion systems, experimentally determined char combustion rates and times were compared to those found by using double resistance theory. It was observed that combustion of lignite chars in the agitated beds proceed faster and lasted in shorter times as expected, mainly due to the removal of ash layer by agitation during the period of char combustion. The influence of the agitation on the combustion of chars from lignites with high-volatile matter content was especially noticeable. Combustion rates increased more as the speed of basket was increased. A combined control mechanism could be used to describe combustion rates of lignite chars.     

螺杆设计方法探讨及在果筐注射机螺杆设计中的应用

介绍了作者设计果筐注射机专用波状螺杆的心得,以此说明设计螺杆的一种思路.借助于相似理论,给出了不同型号果筐注射机专用波状螺杆的设计准则.     

笼式活性炭纤维溶剂回收装置的现状与改进

本文介绍了笼式活性炭纤维溶剂回收装置的现状和改进,提出溶剂回收用活性炭纤维吸附材料细旦化和低气阻的研发方向,以及笼式溶剂回收装置应用中活性炭纤维笼的机械式装填技术及其装置开发,通过溶剂回收工艺设计中气流流向优化和改变活性炭纤维笼结构,实现防止活性炭纤维笼积水的目的。     

氨合成塔内件设计中密封结构的改进

分析了氨合成塔中冷气管、催化剂筐顶盖及层间换热器的密封设计所存在的缺陷 ,介绍了改进型密封结构的特点及其使用效果     

CFD simulations of two stirred tank reactors with stationary catalytic basket

Among the different systems used for laboratory kinetic investigation, stationary catalytic basket stirred tank reactors (SCBSTRs) allow one to study triphasic reactions involving shaped catalyst with large size. The hydrodynamics of these complex reactors is not well known and has been studied experimentally in only a few cases. Despite the difference in the design of two commercial SCBSTRs reported in these works, the local measurements of the liquid-solid mass transfer coefficient inside the catalytic basket revealed the same velocity profile. The aim of the present work is therefore to investigate more accurately the hydrodynamics of the two reactors by means of CFD in order to compare the effect of the blade/baffle hydrodynamic interaction on the flow pattern. Owing to the geometrical complexity of the reactors, the hydrodynamic investigation is based on the k-ε model and the Brinkman-Forsheimer equations. The agreement at the local level with the experimental data (PIV and mass transfer measurements) validates this preliminary work performed with the standard values of the parameters present in the turbulent model and the Brinkman-Forsheimer equations. The simulations reveal in both reactors a ring-shaped vortex around the impeller in the agitation region. The high axial location of its centre induces a reverse flow at the tips of the basket. Owing to the fluid friction in the porous medium, the azimuthal flow in the core region is transformed into a radial flow in the basket where the flow decreases abruptly. Vertical vortices are located at the blade tips and at the downstream face of the baffles or they are located in the basket on both sides of the baffles, depending on the design and the location of the baffles. At the inner radius interface of the basket, the vertical blade impeller induces a rather homogeneous velocity profile, but the pitched blade impeller imposes a high velocity at the plane of symmetry. Therefore the simulations demonstrate that two different local velocity patterns and two different porous media may induce the same mass transfer properties.     

氨汽提尿素装置技术改造

分析了斯那母氨汽提尿素装置生产消耗偏高，负荷低，操作稳定性差，产品质量有待提高等问题的原因，认为合格塔转化率，中压吸收塔效率低，中低压惰气回收系统回收能力不强，造粒喷头设计不佳是问题的主要原因，进而提出解决剖的技改方法。     

Design guidelines for granular particles in a conical centrifugal filter

Essential design criteria for successful drying of granular particles in a conical continuous centrifugal filter are developed in a dimensionless fashion. Four criteria are considered: minimum flow thickness (to ensure sliding bulk flow rather than particulate flow), desaturation position, output dryness and basket failure. The criteria are based on idealised physical models of the machine operation and are written explicitly as functions of the basket size l_out, spin velocity Ω and input flow rate of powder Q_p. The separation of sucrose crystals from liquid molasses is taken as a case study and the successful regime of potential operating points (l_out, Ω) is plotted for a wide range of selected values of flow rate Q_p. Analytical expressions are given for minimum and maximum values of the three independent parameters (l_out, Ω, Q_p) as a function of the slurry and basket properties. The viable operating regime for a conical centrifugal filter is thereby obtained as a function of the slurry and basket properties.