含碰撞式分离元件塔结构优化及水力性能研究

大通量塔可以有效降低塔体直径,节约塔器制造成本,是塔器重要的发展方向。由于塔操作点一般位于雾沫夹带线以上,故提出一种结合高效气液分离方法的塔结构。利用CFD数值模拟方法,分析了新型碰撞式气液分离结构的原理,计算了结构参数对分离效果的影响并对其结构进行优化。基于CFD分析结果,搭建实验平台,研究新型塔水力学性能,结果表明:1)分离元件层数越多、横向间距越小、纵向间距越小,此碰撞分离元件的分离效率越好,但阻力降也越大;2)综合效率和压降以及空间利用率可知,元件层数为2,且横向间距与宽度比值为1.0,纵向间距与宽度比值为0.5时,整个碰撞分离元件的效果最佳;3)当气相流量为定值时,表明改变液相流量对塔板压降无显著作用,当液相流量为定值时,塔板各层压降与气体流量正相关;4)改变液体流量对漏液线及雾沫夹带线无明显影响,且操作范围较广。因此,与传统旋流塔相比,新型含碰撞式分离元件高速塔具有塔径小、处理量大、气液分离效率高及操作范围广等优点,能够大幅降低成本,提升空间利用率,应用前景广泛。

一种星载VDES接收机多通道碰撞信号分离算法

为了解决星载甚高频数据交换系统(Very-high-frequency data exchange system,VDES)接收的碰撞信号在欠定情况下的分离问题,提出一种基于随机近端梯度张量分解的多通道碰撞信号分离算法。该算法根据分离模型对预处理后的信号建立广义协方差矩阵集,堆叠形成张量模型,利用Tucker分解进行压缩得到核张量,减少计算复杂度,并采用随机近端梯度算法优化核张量分解过程,提高了分解精度,最终求得分离矩阵,估计出碰撞的多路源信号。仿真结果表明,该算法在欠定和适定情况下均取得了很好的碰撞信号分离效果。

星载AIS/ADS-B一体化接收系统碰撞信号分离算法

针对星载自动识别系统(AIS)/广播式自动相关监视(ADS-B)一体化接收系统因信号时隙碰撞而严重影响解调正确性的问题,提出一种基于海森矩阵预估计的碰撞信号分离算法。该算法根据多通道碰撞分离模型对目标函数的海森矩阵进行预估计,利用有限内存BFGS(L-BFGS)双循环递归法更新搜索方向,最终得到分离矩阵并估计出原信号。仿真结果表明该算法能够加速目标函数寻优收敛,实现碰撞信号的高效分离。

由astroblaster引发的对多体碰撞问题的探究

针对astroblaster多体碰撞过程,运用分离碰撞模型和同时碰撞模型进行分析,对分离碰撞模型给出了计算公式,对同时碰撞模型则进行了计算机模拟.首先,采用刚性分离模型研究二体、三体碰撞物体的运动速度、弹射高度与碰撞体质量之间的关系,得到弹射高度最大化的条件;其次,利用计算机模拟建立同时碰撞模型,研究物体弹性性质对碰撞的影响,分析物体在碰撞时加速度的变化情况,给出在同时碰撞模型下弹射高度最大化的条件.

入口参数对轴流式油气分离器性能的影响

为进一步提高轴流式油气分离器离心分离段分离效率,本文提出了在分离器入口设置挡板进行初步碰撞分离,并且对不同结构形状的碰撞挡板在不同入口冲击间距和不同入口速度下的分离器压力损失以及最小碰撞分离粒径进行了数值模拟。研究结果表明:随着入口流速的增加,分离器入口碰撞分离段所能分离出的最小粒径减小,分离效率提高,但同时也会产生更大的压损;在所研究的冲击间距范围内,随着冲击间距的增加,碰撞分离段所能分离出的最小粒径变化不大,但产生的压损迅速降低;在三种不同结构形状的挡板中,180°挡板会使分离器底部形成强烈的旋涡,导致压力损失增加,碰撞分离效率降低,增大入口冲击间距可有效减小压力损失。90°挡板与平面挡板所产生的压损最低,并且90°挡板在碰撞分离段所能分离出的最小粒径远小于其他两种结构,分离效果显著。

气液分离器叶片式入口构件整流效果研究

为提高气液分离器的分离效率,提出一种用于重力式气液分离器的新型叶片式入口构件结构。该构件同时具有入口分离与气体整流两项功能。为研究新型叶片式入口构件的整流性能,应用RNG k-ε湍流模型,对气液分离器内流场进行三维数值模拟,确定了安装折弯角度130°~150°、直板长度100~200 mm、斜板长度50~90 mm入口构件以及未安装入口构件的分离器内部的速度分布。研究结果表明:新型叶片式入口构件能显著降低速度不均匀度,抑制回流,使流速分布更加均匀;入口构件折弯角度过大或过小、斜板长度过长均不利于整流,水平板长度对整流效果的影响不明显。研究成果可为气液分离器的优化设计提供依据。

考虑运动副冲击影响的铰链四杆机构动力学分析

采用分离 -碰撞 -接触模型建立含间隙机构的运动微分方程 ,考虑机构驱动装置的机械特性 ,在数值求解过程中根据运动副反力为零等条件判断运动副元素间是否发生分离和碰撞 ,提出了运动副元素发生分离和碰撞的模式假设 ,进而考虑运动副冲击的影响对机构进行动力学分析。研究结果表明 ,所提出的模式假设是合理的 ,在求解运动微分方程过程中考虑运动副冲击影响的算法是可行的。

安钢2~#烧结机烟气脱硫运行实践

对安钢2#烧结机脱硫系统运行过程中存在烟气流量大、流速高、液体夹带明显,导致系统处理负荷增加,主塔、副塔液位不平衡,硫酸铵溶液成分浓度变化不均匀的问题进行了分析。提出了相应的改进措施,通过采用立式除雾器漏隙填充,碰撞分离挡板、架桥导流管设置等优化方法,缓解了烟气夹带、保障了脱硫装置全负荷稳定运行。

弹性弛张筛网干法筛分小粒度难筛物料运动原理解析

鞍矿机械公司在研制干式筛分难筛物料——弛张筛课题中 ,剖析弹性弛张筛网动态抛掷物料的筛分原理。在理论、计算数据、运动图表、实际作业等方面充分证实 :改变传统刚性筛网振动抛掷物料和物料同相位小振幅跳动筛分等方法 ,选用弹性弛张筛网高加速度抛掷物料 ,使物料以不同相位高幅值飞行 ,产生碰撞分离粉料、小颗粒和大颗粒 ,并以高位差冲击透筛的方法 ,是解决干式筛选各种含水、含粉、泥小粒度物料难题 。

Analysis and evaluation on pressure fluctuations in air dense medium fluidized bed

Pressure fluctuations contribute to the instability of separation process in air dense medium fluidized bed, which provides a high motivation for further study of underlying mechanisms. Reasons for generation and propagation of pressure fluctuations in the air dense medium fluidized bed have been discussed.Drift rate and collision rate of particles were employed to deduce the correlation between voidage and pressure fluctuations. Simultaneously, a dynamic pressure fluctuation measuring and analysis system was established. Based on frequency domain analysis and wavelet analysis, collected signals were disassembled and analyzed. Results show gradually intensive motion of particles increases magnitudes of signal components with lower frequencies. As a result of violent particle motion, the magnitude of real pressure signal's frequency experienced an increase as air velocity increased moderately. Wavelet analysis keeps edge features of the real signal and eliminates the noise efficaciously. The frequency of denoised signal is closed to that of pressure signal identified in frequency domain analysis.

Molecular Axis Orientation in Charge Transfer Reactions Determined with a Reaction Microscope

Based on the reaction microscope at the institute of modern physics, the reaction mechanism in molecular ion-atom collisions is investigated experimentally. The features of this system is illustrated by a kinematically complete experhnent performed for the collision process. Using the so-called list-mode data recording technique and the coincidence measurement, the momentum vector of each fragment from the molecular ion were recorded event by event. The orientation of the molecular axis for H2^＋ dissociation reactions could be determined for each event in the off-line analysis. The measured orientation of the molecular ion is believed the same as the one at the instance of collision under axial recoil approximation. The polar angle resolution of the molecular orientation of ±8° was obtained.

Ion-Pair Dissociations of Br CN by Electron Impacts

Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation ion-pair dissociation, there are some experimental challenges in the electron-impact ion-pair dissociation study, in particular, on determination of the energetic threshold. Here we report an experimental development for the ion-pair dissociation study by using the monochromized electron impacts. As an example, the threshold of BrCN→Br^-+CN^+ is determined as 13.78 eV according to the appearance energy of CN^+ signals, meanwhile, the time-sliced ion velocity image of CN^+ is recorded at 16.09 eV and indicates an anisotropic distribution of the CN^+ momentum.

Scaling p_T Distribution in Small Rapidity Region and Pseudorapidity Asymmetry for Charged Hadron in d+Au Collisions at (S_(NN))^(1/2)=200 GeV

With the experimental data from STAR program on the centrality dependence of the PT spectra of charged hadron produced in d＋Au collisions at √^8NN=200 GeV, we show that there also exists a scaling distribution in the backward rapidity regions. Using this scaling distribution, we get the theoretical psedorapidity asymmetry which is basically in agreement with STAR data in the regions of 0≤｜η｜≤0.5 and 0.5 ≤｜η｜≤1. No theoretical models are used in any part of this phenomenological analysis.

Influence of the symmetry energy on the balance energy of the directed flow

The influence of the density-dependent symmetry energy on the balance energy （Ebal） of directed flow from heavy ion collisions （HICs） at incident energies covered by INDRA and MSU experiments is studied, using the updated version of the ultra- relativistic quantum molecular dynamics （UrQMD） model, especially adapted to low-energy heavy ion collisions （HICs）. Four mass-symmetric reactions with total mass numbers between 192 and 394 are chosen for investigating the influence of the symmetry energy on the system-mass dependence of Eual. The results show that the uncertainty in the density dependence of the symmetry potential causes changes of Ebal of the order of several MeV, depending on the type of particle considered. The Ebal of neutrons from HICs is particularly sensitive to the density dependence of the symmetry potential energy, while the system-mass dependence of EbaI of Z = 1 particles is not.

An Isoratio Method and an Isoratio Scaling Phenomenon in Heavy-Ion Collisions

An isoratio method is proposed to study the chemical potential of neutrons(protons) from the yield ratio of isotopes(isotones) differing in neutron-excess(I = N- Z). The measured fragments in the 140 A MeV ^(40),^(48) Ca and^(58),^(64) Ni +~9Be reactions, as well as those in the simulated^(58),^(64) Ni +~9Be reactions by using the antisymmetric molecular dynamics(AMD) model plus the secondary decay model gemini, have been adopted to perform the isoratio analysis.The results of the isoratio method verify that they are similar to that of the well known isoscaling method. The isoratio scaling phenomenon suggested by the isoratio method has also been found in the measured data and the fragments simulated by the AMD + gemini models.