Applied Mechanics and Materials Vols. 501-504

Abstract: This paper using river water as cooling-water to theoretical calculation the refrigerating unit performance of screw chiller. To calculate the change of cooling water flow affected the coefficient of performance under a certain inlet temperature, and compare with other state of affairs. Through the analysis, it could found out that when the cooling-water temperature range between 24~28°C while the outlet temperature is 37°C, it can enhance the refrigerating unit coefficient of performance by reduce the cooling-water flow within limits.

Abstract: Solar energy is a new manner of clean energy with potential for development in the 21st century. In light of the design of TLD (Tuned Liquid Dampers), the technology of solar heated water system is innovatively put forward to supply hot water for residents. Particular attention is given to analyze the limitations of TLD system. Taking a high-rise building of Baotou as an example, the amount of solar radiation is calculated and data collected are presented in Baotou. There is a focus on counting the load of solar heated water through the life water demand, which determines the area of collector. Finally, the feasibility of solar water heating system is showed in the results by the utilization of TLD system, which provides a certain reference action for future research work of TLD system.

Abstract: On the surface of the Earth, methan is usually located in undermined areas, especially in places where the mining was stopped already. The protection of buildings from methan coming out of bedrock can be provided by layer isolation made of suitable type of polymer foil. The entry deals with the matter of designing the isolation against penetrating methan coming out of bedrock into surface line buildings (e.g. shaft, reservoir, water tower etc.).

Abstract: Natural gas pipeline laying process will inevitably go through some of the earthquake-prone areas, these areas of soil subsidence, will cause the pipeline vacant, vacant section of the pipeline failure may cause pipeline rupture. Effects of suspended pipeline stress safety usually have two factors: suspended length and the buoyancy of water. In order to explore the sensitivity of these two factors on suspended pipeline stress, we do numerical simulation of XX suspended pipeline using the general stress analysis software CAESAR II. Research shows that suspended length of pipe is having a greater sensitivity on pipeline stress, and the buoyancy of water is relatively small. The results provide some reference for safety management and selection of pipeline.

Abstract: What the earth obtain the energy annually is ten thousand times of the earth energy consumption at present,but the solar energy has a lower energy density on the earth’s surface .solar energy is the main source of all energy The experimental research was conducted for the heating performance utilizing the solar-assisted heat pump experimental platform. Experimental errors will be caused to flow meter by different measured media and long time usage In order to improve measurement precision and reduce the experimental errors, this test use gravimetric method to calibrate the LZB glass rotor meter and MCE08-787 cumulative flow meter of indoors and outdoors pipes. The paper also presents flow correction coefficient to guarantee both the accuracy and reliability of the experimental results.

Abstract: The array configuration of delta wing and elliptical cylinder vortex generator in the spiral surface channel was studied. By changing the assembly distance s, the triangle wing vortex generator angle of attack α, the elliptical cylinder vortex generator angle of attack β to research the heat transfer and resistance properties under different working conditions. The research model as follow: the heat-medium is water-vapor [H₂, the cold medium of flow is air, Steam temperature is 400K and air inlet temperature is 293K, the Reynolds number ranging from 4000 to 7000.The optimum structure was determined by using numerical simulation method and orthogonal experiment method. The result shows the optimization structure of the combination vortex generator: α=45°, β=45°, s=90mm. Compared with the normal structure, the heat transfer enhancement comprehensive effect of the optimization structure raised about 36.2%~47.6%.

Abstract: Finding the optimal parameters for multi-pump control system of water supply is regarded as a difficult problem with blind source separation (BSS). A motor acceleration or deceleration curve of water supply can be assumed as a weighted sum by feature control parameters, such as pipe line pressure, water flux, and sleeping interval, etc. With the help of destruction of separation model, a group of optimal parameters are found. The solution is to the optimal control parameters for multi-pump control system of water supply. The test results showed that separating precision is 0.856% for two main feature parameters. And an excellent agreement is found with the numerical simulation and the actual test parameters.

Abstract: The reliability models and calculation of fire water supply system was introduced to analyze the reliability of four water-supply modes of automatic fire sprinkler system in high-rise buildings. Study results showed that the reliability of fire pump parallel connected system is the highest, which consists with the provision of the code for design of water extinguishing system of civil buildings when the building height is less than or equal to 120 meters. And the methods of improving reliability of fire water supply system were concluded, which benefitted the optimal design of automatic fire sprinkler system.

Abstract: To reduce the terrorist bombings and the occasional blast damage to people and buildings, a style of steel-sandstone-steel assembly blast walls was designed. To analysis the protective effectiveness of blast walls against the blast wave, The concept of overpressure Protective effects coefficient was proposed. The computational model of assembly blast walls was Established and three-dimensional numerical simulation for the assembly blast walls by using ALE and JWL state equation for the product of explosive detonation was Carried out. Empirical formula calculation results and the test results in the Ref are in good agreement. Using this model the protective effects for blast walls of steel plate with sand, blast walls of steel plate with concrete,concrete blast walls and was studied by 3D numerical simulation. The analyses indicate that protective effectiveness of steel-sandstone-steel blast walls was better than the concrete blast walls and the steel-concrete-steel blast walls.

Abstract: Coastal cities have to face many kinds of natural hazards, which always interact with each other, leading to many losses. And rapid development makes city system too complicated to manage for reducing casualties and economic loss. In order to solve the problems in multi-hazard risk management of coastal cities, this paper attemptted to build a new framework based on historical data and hazard-chain theory, and studied the disaster network with the center of typhoon and earthquake. The framework contains a four-dimensional network composed of factor, hazard, event and vulnerability, and related by risk evaluation, chain probability and losses estimation models. The risk analysis for the network was proposed for estimate the influence over the city, aimed at more effective suggestions of planning and disaster reduction.