Advanced Materials Research Vols. 550-553

Abstract: The liquid lift-up of directed combined trapezoid spray tray (CTST) was studied. The relationship between Liquid lifting capability of combined CTST and clear liquid height on the plate, F-factor based on tray hole was concluded. In single cap and combined several caps, the change of relative and absolute lift-up was also studied. The effect of F-factor to absolute elevating amount was determined by clear liquid height. On the condition of the higher or the lower clear liquid height, the influence of the F-factor to absolute lift-up was considerable. The relation between the pressure drop inside/outside of the bottom gap and liquid lift-up was studied.

Abstract: Pipe is inevitable to be eroded under long-term operation. This research focus on metallurgy analysis about a cracked Inconel 600 pipe, EDS analysis and X-ray structure analysis were applied. Results proven the inner pipe-wall was seriously eroded by activated-sulfur. Results also discovered several areas of this pipe had been suffered from high temperature which exceeded its material re-crystallized temperature. Bumps evolved also increase the shear stress of the material (plastic) causing fracture. These means were adopted to increase corrosion resistance ability: making operation temperature shall be lower than 205°C and the PH value of the media in pipe above 8,increasing thickness of pipe elbow, using composite or ceramic as alternative material of pipe elbow, using inconel 600 with addition of Nb and Ti.

Abstract: A static mixing device with X-style blade structure is designed, and internal structure is described in this paper. Fluid flows through sparse X-style blade static mixing unit, and dense X-style blade static mixing unit. The fluid is subjected impact, separation, circumfluence and merging, and the mixing effects are augmented, and the applicable scope of the mixing device can be widened, and mixing can be more efficient, and structural size can be reduced. The actual turbulent flow inside the mixing units of the static mixing device will be taken into account. The paper can provide foundations for structural improvement, parameters design and optimization of X-style blade static mixing device.

Abstract: This paper mainly conducts experiments on distribution characteristics of the millet and hollow glass beads which have the same average particle diameter and different densities in horizontal T branch pipe, analyzing related data. At the same time it uses BP network optimized by genetic algorithm to conduct simulation prediction. The results show that the distribution fraction of any material in two branch pipes of the same resistance is basically the same, the fluctuation of the material with less density and larger particles is larger when the superficial gas velocity changes. When two control valves opening are not the same, and A control valve fully open, with the B’s reducing, the mass fraction which is assigned to the collection container B has larger overall decline, and the range of it gradually increases. It can be seen that the inflection point of fluid state changing in pipeline is related to density and has nothing to do with particle size. When the superficial gas velocity is smaller than the inflection point, with the decreasing of control valve opening in branch pipe B, the reduction extent of the mass fraction for the materials with less density and larger particles which is assigned to collection container B is larger. The comparison between the genetic algorithm predictive value and the experimental value shows that they are in good agreement. It has a higher prediction accuracy to simulate flow distribution characteristics by using genetic algorithm.

Abstract: With the rapid development of petrochemical industry, the operation condition of pressure vessels under the alternating load was increasing and the probability of fatigue failure was also on the rise. As a result, pressure vessel fatigue analysis is gaining the designer's attention. This paper describes the key steps and techniques of the fatigue analysis of pressure vessel based on Workbench platform using the lock hopper of the coal chemical industry as an example.

Abstract: At the process of lading large structure with vehicle, the landing stage connects the barges and the dock, it needs to meet a requirement to make the car can be driven to the barges smoothly. Here, on the working condition that lading with hydraulic axis car, finite-element analysis and optimization were taken on the force of the landing stage, then optimized the structure of the landing stage to make it and it’s force distribution more reasonable, and reduced the weight of the landing stage.

Abstract: Material fatigue is an important issue in structural design, especially for aircraft that undergo long-term alternating stress. Composite materials have been used extensively in aircraft because of their high specific strength ratio. Using composites made from different reinforcing materials and matrices through various manufacturing methods can yield different levels of performance when structures undergo long-term cyclic stress. Currently, composite materials are extensively used to build aircraft for large commercial carriers such as the Boeing 787 and the Airbus A380. Composite materials are also used in newly-developed small business jets and light aircraft to reduce weight and fuel consumption. The primary objective of this study is to analyze the reaction of light aircraft landing gear under cyclic stress. This study uses finite element analysis software to conduct simulations, and compares the fatigue behavior of aluminum alloy and carbon fiber reinforced composites used in light sport aircraft (LSA) landing gear. We also explore the maximum stress, maximum strain and displacement of landing gear of different shapes (plate and column shapes). Among all the samples tested, column-shaped aluminum alloy landing gear has the lowest maximum stress under a static load; it also has the smallest maximum strain and y-axis displacement. However, column-shaped carbon fiber reinforced composites landing gear sustains approximately twice as much maximum stress under static loads and maximum alternating stress under fatigue loads than those made of aluminum alloy. All landing gear test samples can withstand cyclic stresses of over 108 cycles, except those made of aluminum alloy under 600 kg of load.

Abstract: The fracture failure research on a drilling jar’s top joint was carried out on basis of correlative theories and tests. Macroscopic analysis, dimension measurement and nondestructive testing were done for failure joint. The material’s chemical and physical properties were tested. The drilling strings assembly was analyzed specially and the bending strength ratio between top joint and adapter joint was calculated detailedly. The results showed that the drilling jar’s joint was broken because of fatigue induced by irrational drilling strings assembly and improper matching between top joint and adapter joint. The joint’s fatigue life was reduced further because material’s impact toughness is less than standard value.

Abstract: This paper carried out comparative experimental investigation to test the operation performances of a solar photovoltaic(SPV) direct current(DC) refrigerator using a phase change material(PCM)、a photovoltaic DC refrigerator without PCM and a conventional household one. The solar photovoltaic DC refrigerator with PCM has many advantages on start-stop frequency of the compressor、operation ratio and heat insulation time during the motor stopped. Furthermore, the system is powered by solar energy completely without consuming any grid electricity for running, and is " the green household electric appliance” on real significance, that especially suitable for remote mountains and nomadic areas of fresh food and medical supplies of vaccine, etc.

Abstract: This paper studies the centering accuracy of two large-scale rotating machinery coupling shaft. Laser LD and position sensitive sensors PSD are used to measure and adjust the centering of two shaft coupling, through the analysis of LD-double-PSD-angle prism, LD-double-PSD-plane mirror of the double LD-double-PSD, dual-LD-double PSD centering program, it established a double LD-double -PSD system mathematical model, and the computer simulations to get good results. Based on the theoretical results, the two axes large-scale rotating machinery LD-link LD-double-PSD centering system has been studied and designed.