Advanced Materials Research Vol. 1051

Abstract: Using nonlinear finite element method, the three dimensional nonlinear analysis of the radial steel gate of a reservoir is carried out. In the analysis, the radial steel gate considering and without considering the stiffeners of the panel is analyzed to investigate the effect of the stiffener to the panel. In the corrosion sensitive analysis, the panel of the gate is divided into three sections, and the nonlinear analysis is carried out for each section that is rusted with different corrosion depth. The corrosion sensitive section and the stress variation with the corrosion depth are present.

Abstract: Mixing of two fluids of different densities in a solar storage tank has been simulated by the state of art Lattice Boltzmann Method (LBM). Unlike conventional computational fluid method, there is no need to define an interface shape. In the present simulation with LBM, the interface is determined by the simulation results without any assumption. The present results of mixing of two different fluids can be expanded to multiple components fluids and is expected to provide guidance for chemical fluid mixing in solar storage tanks. Hence to improve the storage capacity and shift the discharge time as demand request.

Abstract: During the heat-up and cool-down processes of nuclear power plants, temperature and pressure histories are to be maintained below the P-T limit curve to prevent the non-ductile failure of the RPV(Reactor Pressure Vessel). The ASME Code Sec. XI, App. G describe the detailed procedure for generating the P-T limit curve. The evaluation procedure is containing the evaluation methods of RT_NDT using 10CFR50.61. However, recently, Alternative fracture toughness requirements were released 10CFR50.61a. Therefore, in this study, RT_NDT of RPV according to the 10CFR50.61a was calculated and used for evaluation of P-T limit curve of a typical RPV under cool-down condition. As a result, it was proven that the P-T curve obtained from 10CFR50.61 is conservative because RT_NDT value obtained from the alternative fracture toughness requirements are significantly low.

Abstract: Through experimental study on creep characteristics of conductors with large aluminum-steel section ratio, the creep characteristic curve of conductors with aluminum-steel section ratio between 11.34 and 14.47 are obtained. It is recommended that the conductor should have a temperature-reduction value of 25°C according to the conductor temperature-reduction value analyzed by amount of creep, which can be used for reference during line design and construction.

Abstract: Sand is used in the pump-sand box-isolation system, studying the initial displacement, particle size and packing rate how to affect the damping ratio by free vibration experiments. The result shows that the initial displacement of the system has less effect on damping ratio, the particle packing rate is a significant influence factor of damping ratio, selecting the appropriate particle packing rate can get the maximum damping ratio, reducing the particle size can increase the system damping ratio, but the damping ratio no longer obviously changes when the particle size of is less than 1.5mm. In general, the packing rate needs to be controlled at below 70% in metal spring or rubber isolator system. This result can provide the basis for the design of particle damping vibration isolation system.

Abstract: Pressure is a very important parameter for combustion diagnostics since pressure is a good indicator of combustion efficiency .As combustion technologies mature, more accurate and less response time pressure diagnosis are needed. Line of sight (LOS) tunable diode laser absorption spectroscopy (TDLAS) provides a fast, nonintrusive, sensitive and reliable solution for quantitative sensing of multiple flow field parameters including gas temperature, components concentration, and mass flux. So far, there is no mature method to measure gas pressure using TDLAS, and it is very important to perfect TDLAS measuring system with the gain of pressure.This paper intends to found a method based on TDLAS for gas pressure measurement. At first, a gas pressure measuring method is presented. Then, an experiment is conducted in a heated static cell to verify this method. A Direct-Absorption-Based Senor which scans H₂O transitions near 1.4 μm was used, and this made the measuring system compact, low cost, simple to operate and quick to response. The experiment successfully measured the pressure in several pressure points, and the results agreed well with the data measured by pressure sensor, average difference is 3.1%.

Abstract: One of the popular ways to use smartphones in public places without disturbing others is to use them with earphones. Earphones are used by people of all ages for listening to music, watching sports/television programs, or even talking to someone over the phone. These devices can be generally classified into two types based on their driver unit, dynamic and BA (Balanced Armature). Dynamic type earphones perform relatively poor in withholding all the sound, letting some sound leak out. On the other hand, BA type earphones fit snuggly into the ears and prevent sound leak. Simultaneously, the users are being blocked out from outside noise. This paper will investigate the volume imbalance between the left and the right BA earphones using a coupler, and how users perceive the volume levels differently. The difference in voltage between the left and the right ones was significant, having 0.8mV with 43.9mV on the left and 44.7mV on the right to form 94dBSPL. This imbalance may cause noise induced deafness when continuously using earphones.

Abstract: This work try to optimize the flow field and concentration field of SCR system. Firstly, the original SCR system is simulated by Fluent and two kinds of guide plates are utilized. The simulation results show that the straight guide plate is slightly better than curve guide plate. The relatively standard deviation of velocity and concentration fields and pressure drop agree with the design rules. To verify the simulation results, a 1:10 scale cold plexiglass test plant is established and this plant is simulated correspondingly. The simulation results are in good agreement with experimental results. So the simulation results of original SCR system are credibly and can guide the practical engineering.

Abstract: Withdrawn by author’s request

Abstract: This paper presents work on improving piezoelectric energy harvesters. Harvesting energy from vibrations has received massive attention due to it being a renewable energy source that has a wide range of applications. Over the years of development, there is always research to further improve and optimise piezoelectric energy harvesters. For this paper, the piezoelectric specimen is made of PZT (Lead Zirconate Titanate), brass reinforced and has 31.8mm length, 12.7mm width and 0.511mm thick. An external beam is implemented to provide deflection amplification which in turn increases the output of the energy harvester. Depending on the configuration of the external beam, it can amplify output voltage from 100% to 300%.