Advanced Materials Research Vols. 287-290

Abstract: The distribution of hoop stress calculated and simulated by Finite Element Method and theoretical calculation in this paper, when the hydrostatic pressure was carried out on the line pipe of Φ 762mm×31.8 mm API SPEC 5L[1] X70 longitudinal seams submerged arc welding(LSAW). The results of simulated by Finite Element Method were accord well with that of theoretical calculation, both of them shown that the hoop stress deviation between pipe inside surface and outside surface was nearly 40MPa, which was about 9% of the hoop stress of outside surface. Besides, the influence of the D/t(diameter-thickness ratio)on the hoop stress were also researched, which shown that the larger the value of D/t was , the fewer that influence on the hoop stress, when D/t=200, the deviation was less than 1%; Or else, the D/t may cause a great stress gradient in the direction of the thickness, even when the D/t=42, the deviation was up to 5%. So that, the effect of the d/t should be taken into account when calculating the hoop stress of pipe with D/t≤42. In other word, a new hydrostatic pressure formula for the heavy wall thickness pipe( D/t≤42) was put forward and adopted when calculating its hydrostatic pressure, that was P =c* Sh (Do² - Di²) / (Do² + Di²), where, c, specification coefficient; Sh, hoop stress; Do, outside diameter; Di, inner diameter.

Abstract: According to high energy losing caused by directly communication between cluster heads and Sink node in LEACH algorithm, a new algorithm based on ant algorithm is formally deriver in this paper. The algorithm takes advantage of the features of ant algorithm, i.e. being easy to be realized, and supporting multi-path to build cluster routing, through the information of its distance and remaining energy of nodes. Then the distance and remaining energy of the neighborhood were integrated in the computation of pheromone concentration. The results of simulation show that compared with LEACH, the algorithm can get a better balance of the energy dissipation and prolong the network lifetime.

Abstract: Along with the rapid development of chemical industry and the progress of science and technology, there exist safety risks for a large number of risk source pipelines. On the basis of the conventional containment measures for risk source leakage, this paper designed two types of emergency devices and corresponding rapid closure methods. One type is the pipeline leak sealing airbag inside the risk source. It is constituted by sealing institutions, diversion institutions, keep institutions and fixed institution. During the work, the sealing airbag gets inflated to realize the rapid closure inside in the piping. It is applicable to the sealing of the heat, water supply, the chemical pipeline, and even large pipe leakages. It also provides the diversion function. The second type the external leakage sealing gasbag for the risk source pipelines. It is compositioned by the belt type rubber air mattress,left and right sides of adjustable bits semi-manipulator mechanism. It is mounted using the belt type rubber layers of tilt superposition around in pipe outside. When needed the air gets inflated inside the gasbag, making each layer of air cushion tension bridle and mutual extruding, to execute rapid closure for the pipeline leakage. These two types of devices are easy to carry, require low professional training, while are highly efficient for the fast closure of the pipeline leakages.

Abstract: Based on cylindrical diffusion theory and characteristics of enriched vibrated Roller Compacted Concrete (RCC), a model of grout permeation was established. According to this model and generalized Darcy’s law, a formula was deduced, which shows the relationship among diffusion radius of grout, grouting pressure, radius of grouting pipe, construction time, viscosity of grout, permeability coefficient of RCC, porosity of RCC and rheological index of grout, computing steps by this formula were presented, and results of computing grout diffusion radius for an equipment of grouting in Roller Compacted Concrete was given, which was developed for construction of RCC dam at Tingzikou hydraulic power station.

Abstract: For the actual needs of fishery production, a rope tension sensor and measuring system with the traceability of changes of fishing cargo weight is designed. Thus the amount of fishing cargo can be evaluated accurately and the blinded operation is avoided.

Abstract: The internal structure of blender truck’s stirring tank is complicated, and accurate analysis of its flow field is important for design and manufacture. This paper carries out numerical simulation of three-dimensional flow field in mixing process by the compute fluid dynamics (CFD) software FLUENT, uses the multi-reference frame and standard k-ε turbulence model to simulate the density in three different conditions. The research result indicates that RNG k-ε turbulence model can simulate the internal flow field in the stirring tank. The tank has a series of advantages, such as large displacement, few left sand, low consumed power and short mixing time, and it has good promotional value.

Abstract: The article is inspired by the exterior shape of the electric fan, which analyzed the extensive developing design space of it. And it also combined the design problem of the existing electric fan in the art function and using function. A multi-function electric fan which simulated the shape of Beijing Olympic auspicious cloud torch has been designed. It discusses the design purpose, the requirements of the electric fan, the designing process, the function design and form design, and the function design is mainly describe the operating principle and a variety of using function. The multi -function including the basic function of the electric fan and the air moistening function, automatic temperature measurement function, automatic ventilation control function, automatic time display function, fire alarm function and music function etc. While shape design pointed out the artistic quality, man-machine quality and analyzed its feasibility. On that basis, it made a conclusion.

Abstract: In dealing with communications problems, this paper found through industry interviews that different form communication tools are used during the form phase in accordance with different product types and that external communication is more difficult than internal communication. In practice, communication tools of sketch and 3D computer graphics are most commonly used. While sketch can be used to quickly make a proposal, client understanding is somewhat inadequate. On the other hand, while 3D computer graphics can be used for clear expression, they require more work time on the part of designers. As a result, this paper introduces a communication tool of 2D and 3D integrated computer graphics to integrate the advantages of both types of tools and then assesses the effectiveness of the tool and sketch. Research results for communications effectiveness showed that the efficiency of sketch was increased. In terms of quality and satisfaction, different factors produced varying evaluation results. If computer graphics software can be integrated as one, realize details, and improve the 3D computer graphics capabilities of designer, then 2D and 3D integrated computer graphics can lead to great improvements in communications efficiency, quality, and satisfaction, achieving the advantages of instant feedback and common consensus with client. These results can be used as a basis and a reference for improvements in arts, design education and industry development.

Abstract: The experiments on dicing monocrystalline silicon wafer using micro abrasive water jet turning were performed. A specifically designed water jet machine tool with four axes was developed and a specially designed cutting head has developed, in which the inside diameter of orifice and focusing tube is f125 mm and f500 mm respectively, while the silicon carbide solid abrasives with average diameter of 25-100 mm was used. In order to control the flow rate of micro abrasives precisely, an abrasive feed system with auger mechanism driven by DC motor reducer was used. The diameters of monocrystalline silicon bars are around 50 mm. Two basic turning methods, i.e. turning with stationary jet and turning with moving jet were applied. The preliminary experimental results such as kerf width, wafer thickness, surface quality etc. were analyzed. It was found that micro abrasive water jet can be used to precisely turn brittle materials like monocrystalline silicon. The turned wafer with thickness of 1 mm above could be achieved. A thinner wafer less than 1 mm is difficult to obtain during experiments because of cracking or chipping. Experiments demonstrate that the wafer surface has macro stripping characteristics similar to linear cutting. It was observed that there is less waviness and smooth surface on the turned wafer when with moving jet. And it depends greatly on the water jet pressure, feed rate of the jet, rotation speed of silicon bar, abrasive particle size as well as flow rate of abrasive. The detailed analysis indicates that the surface roughness of turned wafer with moving jet is around R_a 1.5-5.6 μm, while that of turned wafer with stationary jet is around R_a6.3 μm, when other conditions are same. The results show that surface quality turning with moving jet is obviously better than that of stationary jet. Smaller surface roughness of turned wafer could be obtained when finer abrasive is used. The experiment shows also that the wafer is typically tapered with either the stationary jet or moving jet. There is a concave on the turned surface when feed rate of the jet is too low or dwell time is too long. This is attributed to the jet rebound from one face to the other. Therefore there is an optimizing rotational speed during turning. This study indicates that dicing mono crystalline silicon wafer using micro abrasive water jet turning has potential application in semiconductor industry.

Abstract: Design of infant handcart involves mechanical design, man-machine engineering, art and many other fields. This paper discusses the brand-new concept of function design of infant handcarts under the premise of comfort and safety, which makes ordinary infant handcart have more practical value and social efficiency.