Experimental study on pressure drops in a dividing wall distillation column

Previous studies in the fields of process design and process control [1] have shown the potential benefits that can be achieved through the implementation of thermally coupled distillation sequences, in particular, the dividing wall distillation column. The dividing wall distillation column meets important goals of process intensification, including energy savings, reduction in carbon dioxide emissions and miniaturization. In this paper, an experimental study on the hydrodynamic behavior of a dividing wall distillation column is presented. Several different values for gas and liquid velocities were tested in order to measure pressure drops and identify operational regions; the air/water system was used as the basis for the experimental setup. Results regarding pressure drops (fitted to the model of Stichlmair et al.) provide operational limits for the operation of the packed dividing wall distillation column. According to the results, the experimental dividing wall column can be operated at turbulent regime that is associated to proper mass transfer.     

Experimental studies of momentum transfer in a gas-liquid system in the vicinity of an agitated vessel wall

The results of an experimental investigation of transport processes at the wall of an agitated vessel in a gas-liquid system are presented. Measurements were carried out by means of the electrochemical method. The experiments were performed in a standard agitated vessel of diameter 0.3 m, equipped with a Rushton disc turbine and baffles. The distributions of the diffusion current along the vessel wall were obtained for different values of agitator speed and superficial gas velocity. On the basis of these data, distributions of the shear rate, shear stress, dynamic velocity, friction coefficient and energy dissipated were evaluated. The mean values of the variables were approximated analytically. This paper was presented at the International Workshop on Electrodiffusion Diagnostics of Flows held in Dourdan, France, May 1993.     

压力容器制造超标缺陷安全性分析

针对压力容器制造中常见的超标缺陷 ,提出在细致准确检测缺陷情况基础上 ,可从材料性能、强度校核、常见缺陷产生的附加应力及其控制原则、焊缝质量、密封性试验等诸方面进行缺陷安全性分析。     

Mathematical analysis of the pressure distribution in powder in equilibrium in a conical vessel

A mathematical analysis of the distribution of pressure (vertical stress) in powder mass filled in a conical vessel is presented, taking into account the variation of pressure with the distance from the axis of the cone. The free surface of the powder mass is assumed to be heaped. It is assumed that vertical stress and horizontal stress are interrelated by Rankine's law. From the equilibrium condition of powder mass a fundamental equation has been derived to determine the pressure as a function of both the depth and the distance from the axis of the cone. A solution satisfying the boundary condition at the free surface has been obtained. It is shown that the analysis fits the experimental curves of the distribution of vertical stress     

内压标准椭圆封头壁厚冲压减薄量的研究

通过对内压标准椭圆封头冲压成型后的实际壁厚进行测量,同时参考相关行业标准对相应各点进行应力分析,合理解决了选择内压标准椭圆封头壁厚冲压减薄量的问题。     

压力容器裙座支撑区的疲劳分析

交变载荷作用下的受压容器裙座支撑区是疲劳失效的危险位置.对其运用ANSYS进行应力强度分析,以确定交变应力强度幅.参照工程实际中处理疲劳的一般方法,对危险点按照JB4732-1995《钢制压力容器—分析设计标准》进行疲劳校核.分析结果显示,该处满足疲劳强度要求.     

有限元分析方法在压力容器检验中的应用

运用有限元分析方法,对某压力容器存在的焊接表面缺陷进行分析和计算,获得了缺陷处的应力值及其分布状况,从而判断在该缺陷存在的条件下,压力容器能否在设计条件下正常使用。     

基于区间有限元法的压力容器可靠性分析

压力容器应力计算中,结构的力学参数和尺寸参数具有不确定性。这种不确定性往往是有界的。在工程上可以用一个合理的区间来描述变量的不确定性。对于多个随机变量,利用有限元软件分析变量对结构的影响水平,降低区间数的组合次数,获得压力容器结构的应力区间。根据应力区间的变化范围,得到压力容器的非概率可靠度,从而判断压力容器是否可靠,为压力容器的设计以及评估提出了一种新思路。     

Experimental analysis of static pressure in bins

A pressure transducer with a pressure-high sensitive semiconductor gauge was used to measure distribution of vertical pressure at the base and horizontal wall pressure in a bin packed with glass beads, which are typical cohesionless particles.Even when the glass beads were uniformly supplied to the bin, the vertical pressure at the base was distributed unevenly, with the maximum and minimum values. This seems to be attributable to the “arching” which results from its nonhomogeneous configuration. In addition, the results indicate that the larger the diameter of the bin, the more numerous the extreme values of vertical and horizontal pressure become.This implies that the distribution of particles is the principal mechanism affecting the distribution of pressure in a powder bed. Consequently, to analyze the mechanism of a powder bed, the transference of force among the particles should be evaluated considering the distribution of the particles and paying careful attention to each of the particles in the powder bed.     

压力容器焊接接头疲劳裂纹萌生寿命的探讨

对 1 6Mn R焊接接头进行了控制应变幅条件下的疲劳试验 ,获得其疲劳特性参数以及恒应变幅载荷下的疲劳—寿命关系 ,建立了焊接接头低周疲劳寿命曲线方程 ,并将试验结果同局部应力应变法计算的结果进行了比较 ,为该焊接接头应变疲劳研究提供了理论依据     

压力容器局部区域的应力分析设计

就“99版”《压力容器安全技术监察规程》第 40条有关内容展开分析讨论 ,阐述按常规设计标准和分析设计标准设计计算时 ,材料许用应力、计算方法和判据以及最终应力控制水平方面的差异 ;并阐述这种设计方法在相互交错、相互组合时的处理方法 ;以及局部参照分析设计标准在分析计算中可能会遇到的一些问题。此外 ,还论述了站在 GB1 50常规设计立场上怎样正确理解和运用局部参照分析设计计算的观点和方法     

消除压力容器焊接残余应力技术探讨

焊后热处理是目前压力容器行业中被各方都能接受的消除焊接残余应力的方法,针对这一技术对奥氏体不锈钢制压力容器是否需要焊后热处理、爆炸复合材料的热处理、其他方式代替设备的整体热处理进行了阐述。     

浅谈压力容器在制造过程中如何保证制造品质

根据压力容器制造过程,从材料工艺、焊接、无损检测、热处理、耐压试验等方面,分析了压力容器制造中需要注意的问题。希望对保证容器产品的品质有所帮助。     

浅谈压力容器设计的几个问题

介绍了压力容器的设计要求和设计方法。在设计压力容器时,应该参照有关的国家规范和标准的最新版本。设计得正确、合理与否,不仅涉及到制造、检验等环节的难易程度,影响到压力容器产品的制造成本和运转费用,而且直接关系到产品运行的可靠性。从材料化工用钢材的选用,压力容器材料代用后的设计更改,制造和检验与验收方面分析了压力容器设计中容易忽视的问题。     

试验压力下容器法兰强度的探讨

采用设备法兰联接压力容器.在选用设备法兰时,不仅要考虑容器的设计压力、允许工作压力,还必须确定试验压力下的法兰强度,以保证满足工况条件下设备法兰的强度和密封要求.     

A theory of the pressure distribution in powder in equilibrium in a cylindrical vessel

A mathematical analysis of the distribution of pressure (vertical stress) in a powder mass filled in a cylindrical vessel is presented, taking into account the variation of pressure with the distance from the axis of the cylinder. The free surface of the powder mass is assumed to be even. It is assumed that vertical stress and horizontal stress are interrelated by Rankine's law. From the equilibrium condition of the powder mass a fundamental equation has been derived to determine the pressure as a function of both the depth and the distance from the axis of the cylinder. A solution satisfying the boundary condition at the free surface has been obtained. It contains a number of indeterminate constants and is reduced to Janssen's formula, provided that the pressure is independent of the distance from the axis of the cylinder. It is shown that our theory agrees fairly well with the experimental data of Yoshioka .