Advanced Materials Research Vols. 753-755

Abstract: Considering the un-saturated in the experiment, the purpose of this paper is achieving a simple 1d molds unsaturated simulation of the filling process through the compiled software pore-flow and compare the single-scale result with the dual-scale result.

Abstract: Using a CFD software, the numerical simulation of a 2×300MW direct air-cooled unit is done by multi-stage modeling method. the effect of the environmental wind on the heat-exchanging performance of the air-cooling island is analyzed by numerical simulation. The effects of different wind velocities and directions on exterior flow field and heat-exchanging efficiency are analyzed. The reasons of hot air recirculation and the decrease of the fans’ output are found. The heat transfer performance of air-cooled island is affected after the installation of windproof net. The result shows that the form of low-pressure area is the main reason for the hot air reflow and the decreace of the fan’s output; An improved flow field can be got after installing the windproof net. The volumetric effectiveness can be increased by 8.5% at a wind speed of 9 m/s.

Abstract: Modular modeling methods based on the reasonable simplifying and supposing of hydraulic system of demolishing robots are proposed in this paper, dynamic mathematical model of each hydraulic element of demolishing robots is set up by the dynamic system analysis software package Simulink of Matlab, response characteristic curve is obtained by the simulation, and analysis of the simulation results is operated in this paper. The experimental results explicate that the hydraulic system is stably, real-time, low-cost, and easy to expand; it can meet the applying requirements of demolishing robots, and it provides the theory basis for the project applying of the hydraulic system of demolishing robots.

Abstract: The exhaust steam heat of steam driven feed pump small steam turbine is considerable in modern coal-fired power generating unit, most of which is adopted the way of wet cooling through the condenser as same as main steam turbine for condensing steam turbine unit, all the waste heat with it is taken away by circulating cooling water and not used effectively. This paper will propose the way of part of exhausted steam of small steam turbine recycled to the regenerative extraction steam system to heat condensate based on steam ejector heat pump, so as to use the exhausted steam effectively and analyze the thermal economic index of different schemes by using equivalent enthalpy drop method. The results show that it produces best economic benefits when exit steam of steam ejector heat pump is recycled to steam extraction of the fourth section.

Abstract: In this paper the seat vibration acceleration response was reduced through flow passage modification of the centrifugal pump which could decrease the fluid excitation of the pump. CFD simulation technology was applied to optimize the fluid field of the multi-stage centrifugal pump, and then the velocity, pressure fluctuation and fluid excitation were concerned to investigate the effect of optimization. Finally, the influence of fluid field modification on the seat vibration response was verified experimentally.

Abstract: Electrical Submersible-motor-driven Progressive Cavity Pumping (ESPCP) oil extraction technology has the advantages of sample technology and management convenience. ESPCP is suitable for the viscous, containing sand, high gas oil ratio oil extraction. Developing history of ESPCP is introduced and the structure and principle are analyzed. The advantages of ESPCP are compared with other oil extraction technology. At last, developing status is discussed and the developing trend is investigated.

Abstract: With increasing of high pressure or condenser temperature, the cycle (TSCV+TG) has a downward trend and the cycle (TSCE+TG) has an increasing trend. With increasing of the evaporating temperature, the cycle (TSCV+TG) has an increasing trend and the cycle (TSCE+TG) has a downward trend.

Abstract: With increasing of compressor high pressure, the cycle performance of R134a or the cycle of R1234yf has a downward trend. With increasing of the evaporating temperature, the cycle performance of R134a or the cycle of R1234yf has an increasing trend. With increasing of outlet temperature of condenser, the performance of R134a or the cycle of R1234yf has a downward trend. With increasing of intermediate pressure or discharge temperature, the performances of all cycles are decreased. Under same contrast conditions, the cycle performance of R134a is better than the cycle of R1234yf.

Abstract: With increasing of high pressure, the two stage compression cycle with two gas cooler has a downward trend. With increasing of the evaporating temperature, the two stage compression cycle with two gas cooler has an increasing trend. With increasing of outlet temperature of condenser; the two stage compression cycle with two gas cooler has a downward trend. With increasing of intermediate pressure, the performances of the two stage compression cycle with two gas cooler are decreased.

Abstract: With increasing of compressor high pressure, the two stage cycle with an expander has a downward trend. With increasing of the evaporating temperature, the two stage cycle with an expander has an increasing trend. With increasing of outlet temperature of condenser; the two stage cycle with an expander has a downward trend. With increasing of intermediate pressure, the performance of the two stage cycle with an expander is decreased.