Advanced Materials Research Vols. 622-623

Abstract: This paper introduces the smart substation hardware-in-loop simulation training system structure based on the analysis of the smart substation simulation training requirements. The training system scheme has been designed according to the different training requirements to support training of staffs in smart substation for operating and maintenance in all possible ways. Combining with the practical solutions, the application of the training system will be introduced. This design scheme will take important effect in the development of smart substation and its operating and maintenance training.

Abstract: This work deals with periodic flow, friction loss and heat transfer characteristics in a constant temperature-surfaced circular tube fitted with rib vortex generators (RVG). The computations are based on the finite volume method with the SIMPLE algorithm implemented. The fluid flow and heat transfer behaviors are presented for Reynolds numbers ranging from 100 to 1000. To generate two main vortex flows through the tested section, the 45o RVGs are mounted repeatedly in in-line arrangements on the top and bottom walls and in the central area of the tested section. Effects of different RVG heights, BR in a range from 0.1D to 0.3D with a single pitch of 1.5D on heat transfer and friction losses in the test section are examined. It is apparent that the vortex flows created by the RVG exist and help to induce periodically impinging flows on a sidewall leading to drastic increase in the heat transfer rate over the test section. The computational results reveal that the optimum thermal performance is about 2.38 for using the RVG height of 0.2D for the RVG placed on the tube walls at the highest Re value.

Abstract: In today`s scenario of depleting conventional fossil fuels biomass provides an alternate source of energy. Gasification is a chemical process that converts carbonaceous materials like biomass into useful convenient gaseous fuels or chemical feedstock. The gasification process uses an agent air or oxygen, hydrogen or steam to convert carbonaceous materials into gaseous products. As air gasification produces poor quality syngas, oxygen is used as gasifying agent for biomass gasification. Biomass gasification with oxygen as gasifying agent has great potential in applications like IGCC (Integrated Gasification combined cycle), Chemical Production and Fischer-tropsch products. In this paper the simulation model of a biomass gasifier for different biomass like charcoal, rice husk and wood pellets with oxygen and air as a gasifying agent is developed using ASPEN Plus. The model predicts syngas composition, heating value, temperature, pressure and quantity of gas produced. These results are obtained for various feedstocks like wood pallets, rice husk, and Indian coal on the basis of proximate and ultimate analysis.

Abstract: Ball grid array is an interconnection method widely used in the electronic packaging industry. The reliability of the solder ball is being improved by introducing new materials for the solder ball. In this study, the stress response of BGA solder ball during minimum vertical loading is analyzed through simulation. The stress response between two types of solder ball, Normal BGA and Micropearl BGA are compared. The Micropearl BGA is a solder ball which contains polymer core. The vertical loading forces used were 1N and 3N. A commercial computational software ANSYS was used for the simulation. The simulation results showed that the Normal BGA exhibited higher stress response.

Abstract: Wire bonding process is an interconnection method adopted in the semiconductor packaging manufactory. One of the method used to assess the reliability and bond strength of the bonded wires are wire bond shear test .In this study, simulation on wire bond shear test is done to evaluate the stress response of the bonded wire when sheared on a hemispherical surface bond pad. The contrast between three types of wire material:gold(Au), aluminum(Al) and copper(Cu) were carry out to examine the effects of wire material on the stress response of bonded wire during wire bond shear test. The simulation results showed that copper wire bond induces highest stress and gold wire exhibits the least stress response.

Abstract: Wire bonding process is first level interconnection technology used in the semiconductor packaging industry. The wire bond shear tests are used in the industry to examine the bond strength and reliability of the bonded wires. Hence, in this study thesimulation on wire bond shear test is performed on a sharp groove surface bond pad. ANSYS ver 11 was used to perform the simulation. The stress response of the bonded wires are investigated.The effects of three wire materials gold(Au), aluminum(Al) and copper(Cu) on the stress response during shear test were examined. The simulation results showed that copper wire bond induces highest stress and gold wire exhibits the least stress response.

Abstract: We have fabricated Au, Cu, and Pt nanowires by using a shadow deposition technique. We have then investigated optical properties of these nanowires by studying the second harmonic generation (SHG) spectra. With experimental and theoretical studies, we have discovered that the surface plasmon resonance was served as an origin of the enhancement of the SH response from the metallic nanowires.

Abstract: This study aims to determine flow stress of a steel tube by using hydraulic bulge test. A new proposed analytical model for analyzing bulge shapes of hydroformed tubes is postulated. Bulge test apparatus designed using FEA simulation of hydroforming and STKM 11A steel tubes are used in the hydraulic bulge test. Bulge heights and internal pressures are measured during bulge testing. Tube thicknesses at vertex of a bulge shape are measured by a dial caliper gauge. Bulge curvatures and contact points are measured by taking digital photos of bulge shapes combined with measurement methods in CAD software. Effective stress - strain relationships are obtained from the newly developed analytical model using those measured values. Flow stress curves obtained from the effective stress – strain relationships are compared with those by other researchers and tensile test. Finite element analysis methods are used to conduct simulation of tube hydroforming using the flow stress curves. Predicted internal pressures versus bulge heights and tube thicknesses are compared with experimental results. Verification of the developed analytical model is presented. The flow stress at neck point of formed tube is determined.

Abstract: This paper establishes a point electrode model, and obtain the analytic equation of electric fields produced by this model using vector superposition. Then do some further research to the analytic equation using ring current source model, and obtain the analytic equation of electric fields produced by ring current source. At last do some simulation about the analytic equation of electric fields, that can obtain the value of electric fields in the air - sea - the sea-bed three-media model.

Abstract: In this paper, we investigate the three finger micro/nano gripper using piezoelectric actuator. A comparison of various materials as structural and actuator is presented. Different combination of Silicon, Quartz (SiO₂), and Aluminium as structural material with PZT4, and PZT-5H as actuating material have been analysed. Results show that the combination of Aluminium with PZT-5H produces more displacement than the others.