Applied Mechanics and Materials Vols. 71-78

Abstract: Based on the principle and method of computational fluid dynamics (CFD), using the software, FLUENT, the inner water flow field in a hydrocyclone with air column was simulated and the flow details were studied roundly. This article analyzed the three-dimensional velocity field distribution, pressure field distribution and testified the reliability of numerical simulation to a certain extent. The “mixture” model was used to simulate the air column the first time and contrasted with experimental result, the simulated effect was proved effective. The results of this paper provided a good base and reference for the further research of solid-liquid separation.

Abstract: Because of excessive pressure loss when the gas went through distributor in fluidized bed (FB), based on the principle and method of computational fluid dynamics (CFD), using the software, FLUENT, the inner flow field in the fluidized bed with distributor was simulated. This article analyzed the three-dimensional velocity field distribution, pressure field distribution under the different arrangement of hole form. and the good advice was given on the structural optimization of the cold distributor.

Abstract: Based on the analysis of water asset management performance indicators, this paper proposes a performance model evaluation of water asset management that based on entropy theory and empirical study of one of the Reservoirs as an example to indicate that the model method is feasible.

Abstract: In this paper, the desulfurization of Fangshan coal was carried out by tetrachloroethylene extraction under ultrasonic and microwave irradiation. The GC-MS analysis of the tetrachloroethylene extraction reveals that organic sulfur in coal can be removed by tetrachloroethylene extract under ultrasonic and microwave irradiation. It is found that microwave irradiation time has great effect on organic sulfur removal. With the microwave irradiation time increases, the efficiency of organic sulfur removal increases. The desulphurization yield reaches maximum, 45%, when the time is 30 minutes or more. It can be clearly seen that Fangshan coal was oxidated by peroxyacetic acid under ultrasonic and microwave irradiation. From the XPS analysis of the macerals of the coal, most of the inorganic sulfur and organic sulfur are removed, especially thioether and thioalcohol which can be completely removed. These results suggest that microwave is an effective way to remove sulfur in coal.

Abstract: In this study, the regeneration capability of the modified semi-coke supported ZnFe₂O₄ sorbent for the desulfurization of hot coal gas was investigated. With assistance of ultrasonic irradiation, the sorbent of modified semi-coke supported ZnFe₂O₄ was prepared by the co-precipitation method. Then the sorbent was tested 3 cycle experiments of sulfidation and regeneration in a fixed-bed reactor. After 3 cycle experiments of sulfidation, the sulfur capacity changed from 29.7% to 26% and the mechanical strength was about 35 N.cm^-1, declined slightly. After the regeneration in atmosphere of H₂O and O₂, the oxide and a little sulfade existed in the XRD patterns. The structure properties of the sorbents were characterized by BET. The surface area and pore volume decreased slightly after the regeneration.

Abstract: Material flow analysis (MFA) has become a useful tool fo to analyze the metabolism of social systems. This paper proposes to use the indicators derived from MFA, complemented with water and energy indicators, to analyze the efficiency and the materialization ranks of Ningdong energy(coal) and coal chemical base (China). The companies in the base have many opportunities to improve on these aspects and the indicators can measure and reflect their evolution. In addition, the results show the importance that some flows such as water inputs which often are omitted, can have in some study cases.

Abstract: Application of heat pump technology is a effective way to achieve energy saving and emission reduction.In order to propose the heat pump system suitable for marine air conditioning,this paper takes a bulk carrier as the research object,calculates the annual dynamic cool and heat loads of ship,proposes five kinds of cold and heat source optional schemes and selects the equipments.On this basis,five optional schemes are evaluated by using the method of AHP from the following aspects:economic, energy consumption, environment, weight and size.The result shows that comprehensive properties of adopting double stage coupling water source heat pump in ship are better than other schemes.

Abstract: This study describes the results on the performance of one vehicle air conditioning system. The coefficient of performance, evaporator cooling capacity, compressor power consumption, total mass flow rate, vapor mass flow rate, liquid mass flow rate and oil in circulation, pressures and temperatures of refrigerant at every component (inlets and outlets) are measured and analyzed with the variation of the outside temperatures at the evaporator and condenser, the speed of the compressor, refrigerant charge and oil charge. The systematical experimental results obtained from this real-size test system depict the relations between the above parameters in a vehicle air conditioning system, which constitute a useful source for vehicle air conditioning systems design and analysis. The vapor quality (two-phase flow) measurements realized in this work provide an extremely important tool for diagnosing the system performances.

Abstract: Based on the analysis of water asset management performance indicators, this paper proposes a performance model evaluation of water asset management that based on entropy theory and empirical study of one of the Reservoirs as an example to indicate that the model method is feasible.

Abstract: The different mathematical and physical models of one-dimension or two-dimension for premixed air combustion in the ring porous medium burner are reported in the literatures. In this paper, a case of combustion of methane/air ratio 0.6, the fluid velocity 0.2m/s and the adiabatic wall of burner is simulated by three-dimensional single temperature model. The numerical results show a good agreement with two-dimensional model for combustion characteristics, such as temperature and velocity distributions in burner, which provides important theoretical basis for the development of new porous medium burners.