Applied Mechanics and Materials Vol. 464

Abstract: Used Profili, Gambit and FLUENT software to build 2D model of the horizontal wave flow turbine power plant which developed by Shanghai Ocean University, and to simulate its pressure and velocity flow field under the RNG k-ε turbulence model with rotational speed accordingly 75r/min, 110r/min and 150r/min while the incoming flow velocity was 2m / s .By showing and analysing its pressure speed clouds, summarized the flow regular impacts to the rotaional turbine,which provided an important numerical reference to the blade strcture optimization and its strength check and indicated a right simulation method to solve the similar fluid simulation project.

Abstract: This work collects the experimental results obtained in the Thermal Fluid Dynamics Lab at the Department of Energy, Systems, Land and Constructions Engineering at the University of Pisa, concerning a basic physics research on the influence of ultrasounds in single phase free convection and in subcooled boiling, at atmospheric pressure. The ultrasounds are applied at the set frequency of 40 kHz, with a transducer output changing from 300 to 500W, on a circular horizontal cylinder heated by Joule effect, immersed in distilled water. The tests in single phase free convection, without ultrasonic waves, are validated by means of the classical correlations reported in literature, but they do not produce distinctive augmentation of the heat transfer. The enhancement of the heat transfer coefficient is maximum in subcooled boiling conditions (about 57%). In this regime a detailed investigation was performed to optimize the variables involved, such as the ultrasound generator power, the position of the cylinder and, especially, the subcooling degree. This paper, makes clear systematically the effects of ultrasounds on the heat transfer and shows as they could be very useful as cooling system for the last generation electronic components.

Abstract: A computational fluid dynamics (CFD) model of tank powertrain compartment was constructed for cooling air flow and heat transfer analysis. The key points temperatures of the powertrain compartment were tested, and the numerical values have a good agreement with the measurement datas. Detailed cooling air flow field distributing characteristic through radiators in the powertrain compartment were obtained through numerical method, with different fan speeds and ambient wind speeds. These results can provide the basis for the choice of the fan speed on specific condition and the air flow distribution of the radiator.

Abstract: The bath static experiments were conducted to study the sewage treatment effects by the typical yellow-brown soil of Xuzhou, the results obtained in this study showed that: The COD removal rate was about 50% or so through experimental treatment. The three days dynamic and intermittent soil column experiments show that: The COD removal rate was more than 80% by the simulated soil column experiments; the dynamic intermittent and soil column experiment both show that soil thickness influence the effect of phosphorus removal, the thicker layers, the better removal rate; the effective depth of NH4-N removal is deeper than 15cm.

Abstract: This thesis is based on the target of the sludge which was dehydrated and percolated by sewage treatment plant. It conducts the feasibility analysis for the agricultural usage of sludge in cities, and carries out composting experiment of dehydrated and filtered sludge which lasts for about fifteen days. This thesis also does some research on the techniques of composting and parameters of sludge. This thesis has some researches on the temperature of sludge, moisture, organic matter, pH, total phosphorus content of nitrogen, heavy metals content and forms, the germination rate index (GI), and other changes during the process of composting. The results show that, after the composting, there has a significant decline in moisture content of the sludge and the organic matters; pH remains neutral; nitrogen has declined; total phosphorus increased. Composting can make majority of heavy metals reduced which was absorbed by the plant that means the decline of unstable heavy metal content. After the composting, germinations rate index (GI) is more than 50 percent, which shows that the composting products have no toxicity and indicates the maturity of composting. Through the analysis of the organic matter of the sludge plant, PH, plant nutrients (N, P,) content, heavy metal content and its forms of distribution and germination rate index (GI), it shows that the sludge of this plant has a good agricultural prospect.

Abstract: Chemically enhanced primary treatment (CEPT) process have advantages of low pollution load and low costs, it can greatly improve the removal efficiency of organic matter by primary treatment , so the process has been studied widely and intensively. In this thesis, the mechanism, coagulant type, dosage and precipitation time were studied.

Abstract: We measured chrominance of chrysotile powder using a colorimeter and a luminance meter under different light sources with seven color filters to test feasibility for the real time asbestos detector development. Chrysotile powder was prepared by heating asbestos fabric at 150 °C for 1hr and hydrochloric acid treatment was followed to remove other elements. Refractive index liquid was used as a color changing analyte to observe the change in chrominance of chrysotile. From the measurements, it revealed that a colorimeter was more suitable for the chrysotile detection by the maximum change in chrominance, especially in the short wave length range of blue regions. A luminance meter was not able to separate the difference in chrominance depending on different color and light sources regardless dyeing. It might be due to that reflected light from chrysotile particle was relatively weaker than that from illuminated area. It is our suggestion that the real time monitoring of asbestos in indoor air can be possible using a color sensor, specified to the unique wavelength of dyed chrysotile based on our chrominance data.

Abstract: In this paper, we study the Pearl River cadmium spill. Based on the reaction diffusion equations, we can monitor the concentration of pollutants any time. We find that in 20 kilometers distance from pollution sources, the concentration of cadmium is high. At last, we improve the model.

Abstract: China has become the worlds largest emitter in carbon dioxide. Power generation enterprises are the concentrated source of carbon dioxide emission. As the core mechanism in carbon trading market, price mechanism influences the markets function a lot. This paper analyses the initial carbon emission price mechanism and the forming mechanism and influence factors and puts forward the design scheme to implement carbon emission right price mechanism. Finally it makes suggestion to perfect the price control mechanism. The conclusion shows that the initial carbon dioxide emission right price control is beneficial to control and reduce the carbon dioxide emission from generation enterprise.

Abstract: Electrical-performance test (hereafter referred to as E-test) has always been one of the difficulties in final testing procedures for semiconductor. The accuracy, rapidity and generality are difficult to achieve in the E-test. This paper proposes a test method based on the characteristics of the E-test workstation of test handler for semiconductor, in which the whole test procedure is divided into two terminals: the control and the test terminal. The control terminal is integrated into the control system of test handler, while the test terminal is independently designed with generality for different semiconductor products. To achieve an ideal performance, the parallel work trait of E-test in this method is discussed. Finally, the method has been successfully implemented on the test handler for semiconductor in actual production.