Advanced Materials Research Vols. 614-615

Abstract: In the dense phase pneumatic conveying lab table, used horizontal shrinked pipeline as transmission pipe. Used compressed air as conveying power and dry gypsum powder as transported materials, then conducted with gas-solid conveying experiment. Through the experiment, resulted show change law and influence factors of pressure drop in horizontal shrinked pipeline under different transportation conditions.In this study. The results showed that diameter ratio, solid and gas mass ratio and diffusion angle could affect the pressure drop of the pipeline .

Abstract: This study develops a methodology to assess the probability for the degraded PWR steam generator to rupture first in the reactor coolant pressure boundary, under severe accident conditions with countercurrent natural circulating high temperature gas in the hot leg and SG tubes. The first step performs thermal-hydraulic analysis to predict the creep rupture parameter of the tubes in severe accident. The next step applies the creep rupture models to test the potential for the degraded SG to rupture before the hot leg. Then, the mean of the SG tube rupture probability was applied to estimate large early release frequency in LERF (Large and Early Release Frequency) model, and the overall LERF risk due to the Induced SGTR was calculated. In the final step, implementation of severe accident management guidance (SAMG), such as the RCS depressurization and refilling to SG, is evaluated using PSA approach. It can be found that strategy of RCS depressurization and refilling to SG can mitigate the result of induced SGTR and LERF effectively.

Abstract: Recent years, automobile air-conditioner control system is particularly important as the automobile air-conditioner is becoming an important indicator to measure the comfort of a car. This paper introduces the hardware and software design of the system based on STC12C5A60S2 microcontroller.The hardware design part includes the circuits design of motor and fan, and the software design part describes the way to realize the modes conversion function. Experiments show that the automobile air-conditioner system can reach high control accuracy and it's practical.

Abstract: This paper describes the control system design based on the LIN bus on car air conditioning. Using the STMicroelectronics STM32 family of 32-bit ARM Cortex M3 core SCM as the controller, a LIN bus application and design in the modern automotive air conditioning control system are proposed, resulting to achieve reliable, stable, simple wiring harness, and low-cost of automotive air-conditioning control system.

Abstract: Annual cold heat adjustment is one of the key problems in the practical application of ground-source heat pump system. According to the energy-consuming characteristics of the building in hot summer and warm winter area zone and engineering practice, the author puts forward the multi-level heat shunt ground source heat pump systems(GSHPS). Reasonable system can be matched according to the characteristics of the cold water chiller and the water source heat pump, which takes full advantages of soil cold/heat source, improves the efficiency of the soil heat exchanger, and balances underground temperature field effectively.

Abstract: The article builds up the mathematics model about the fan coil chilled water system energy consumption. By the model, it calculates the energy consumption under the different flux ratio, the result shows that the optimal water parameter is different from the design parameter, it has relation with the chilled water pump head. When the pump head value is larger, adopting the smaller design flux’s parameter; when the pump head value is smaller, adopting the larger design flux’s parameter. So to make the energy consumption minimum, the water parameter should be computered.

Abstract: Operating characteristics of variable cross section area of main duct in the main-branch central exhaust system was simulated based on various stories, operation rate and cross section area of main duct by FLUENT. The results show that there are certain obvious induced flow in the lower part of the system when the users in the upper floor work in the central exhaust system,and the internal pressure of main duct appears low- high-low trend in the system from the bottom to the top floor. The maximum pressure position is not in the bottom, but in the middle and lower floor of the system, where is the most disadvantageous floors of the exhaust system. It indicates that 400 mm x 500 mm is the necessary cross section area of main exhaust duct for 10 layers buildings,and 400 mm x 750 mm is the necessary one for 20 layers buildings.

Abstract: Small composite desiccant wheels based on ceramic are designed and developed. The experiments test the influence of the rotating speed and wheel thickness on the dehumidification performance. Furthermore the dehumidification performance of the composite desiccant wheel is compared with the silica gel wheel. The experimental results show increasing the rotating speed of the desiccant wheel can improve the moisture removal capacity. Compared with the silica gel wheel, the moisture removal amounts of the thin composite desiccant wheel are about similar with that of the thick silica gel wheel. It is further indentified that the new composite desiccant wheel can reduce the size of the dehumidifier and has more potential for residential building field.

Abstract: In this paper, a heat pump water heating system with waste heat recovery in ammonia refrigeration system was put forward, based on the practical project analysis of energy demand and waste heat emission. Based on the operating characteristics of ammonia refrigeration system, the ammonia heat exchanger was designed to be installed in series on the ammonia main pipe, which can ensure the system operate efficiently and reliably. Through the analysis of measured data, significant economic benefits had been brought about by using the heat pump water heating system. This project can save 2.19 million RMB in annual operating cost, and the investment recovery period will be only 1.5 years. The heat pump water heating system has excellent development prospect.

Abstract: The automotive air conditioning compressor (AAC) is belt-driven by the engine. The compressor speed is directly proportional to the engine speed. Therefore, the cooling capacity will vary as the engine speed changes. To meet the air conditioning (AC) demand, the compressor continually cycles on and off. In the research, the compressor of the AAC is driven by an electric motor which in turn is operated by electrical battery (12 volt). The use of direct current compressor (DCC) is seen as a solution of the existing system. Using the proposed system, DCC gets significant improvements in energy efficiency. Compared with AAC system, the energy conservation effect is about 77.5% to 86.35%.