Shao Hua Li

Design and Implementation of Experimental System for Comprehensive Utilization of Oil Shale

The single model of oil shale development, which is, burning in boiler for power generation and distillation for shale oil, may cause enormous waste of oil-gas resources and semi-coke. For energy conservation and efficiency improvement, it is necessary to realize the comprehensive utilization of oil shale. The development of experimental system is foundation of further studying. In the paper, an experimental system for comprehensive utilization of oil shale is designed and realized. These includes: spouted bed combustor and shale ash collection system, oil shale retort with solid heat carrier and shale oil recovery system. With the system, the realistic simulation under different condition such as different kinds of oil shale, operation condition can be studied. This work lays an experimental foundation for the further study of comprehensive utilization of oil shale.

Modeling of an Oil Shale Low Temperature Retorting Process by Using Aspen Plus

In this paper, the feasibility of employing Aspen Plus in the simulation of oil shale retorting would be discussed by modeling of a low temperature retorting process with fischer assay experimental condition. The samples of 4th layer of No.1 deposit and 11th layer of No.2 deposit of Huadian oil shale have been simulated, and draw a comparison between the simulation and determination results of oil content, moisture content, retorting gas yield, semi-coke yield and ultimate analysis. The tolerance between the simulation and determination results is within a reasonable range, which indicate that the process built and the physical method selected are correct and reasonable and would provide reference for building the process of oil shale comprehensive utilization system.

The Study of Unsteady Flow in Cascade Based on Numerical Simulation

The effect of unsteady wake on cascade blade was studied with numerical simulation. The influence of wake on flow field and heat transfer around blade is analyzed by increasing the axial spacing between the vane and blade. The conclusions are as follows: The smaller the distance of stator and rotor is, the more uneven the circumferential distribution is. When the axial spacing increases, the wake of vane which spread to rotor decays gradually and the influences of wake on blade also decrease. Because of the impact of wake, the heat transfer of blade leading edge is very strong. When wake mixes with the mainstream gradually, the heat transfer coefficient of blade surface also decreases gradually. With the augment of axial space, the heat transfer coefficient of blade leading edge is reduced gradually, but the influence on suction surface and pressure surface is small.

Effect of Operating Conditions on the Efficiency of Circulating Fluidized Bed Flue Gas Desulphurization

In this paper, a study was carried out on the circulating fluidized bed (CFB) flue gas desulfurization system of a power plant. A problem of the desulfurization system has arisen during text run that SO2 removal efficiency is too low. In this study, the effect of SO2 concentration and outlet temperature on desulfurization efficiency was carried out on a text stand. The results showed that the desulfurization efficiency decreased as outlet temperature increased. The desulfurization efficiency increased 20 percents when the outlet temperature decreased from 84°C to 75°C. In the outlet temperature of 75°C, the desulfurization efficiency was the highest. In the condition of other parameters remaining unchanged, the removal efficiency first increased and then decreased with the SO2 concentration increased. Under the text conditions, the highest desulfurization efficiency turned up at the inlet SO2 concentration of 1700mg/m3 to 1900mg/m3. The exit temperature has been adjusted according to the results. The operational results showed that decreased the outlet temperature to 75 °C led the desulfurization efficiency rising to 88%.

Numerical Simulation of Venturi Device in Flue-Gas Circulating Fluidized Bed Desulphurization Tower

Venturi device has important effect on pressure loss and flow field of flue-gas circulating fluidized bed desulphurization tower. Desulfurization tower is huge. Experimental study is difficult and costly. For these problems, PC-SIMPLE algorithm of Euler model of Fluent software is applied and flow condition of four different kinds Venturi tube are simulated in this paper. The pressure loss of curved Venturi is minimum. Three groups of Venturi tube can get uniform velocity field in the tower. Turbulence intensity of a group Venturi tube is maximum, followed by curved Venturi tube. But the turbulence intensity gradient of a group Venturi tube inside the absorber is also the largest. In order to get low pressure loss and better flow field, three groups Venturi tube is optimum.

Study on Reliability Analysis of Distributed Control System of Nuclear Power Plant

The reliability of the nuclear power plant DCS is analyzed using Markov process to establish a mathematical model. And the initial use of the model on the three indicators of reliability parameters of nuclear power plants is calculated. The results showed that the model is correct,reliable and error rate is 9×10-10.DCS applies to preliminary analysis of the reliability of nuclear power DCS. Nuclear power plant DCS reliability is high enough, the minimum time of continuous operation is up to 66667 h, compared to conventional control methods more safe and reliable.

An Experimental Investigation of Flow Characteristics Downstream of Discrete Film Cooling Holes on Turbine Blade Leading Edge

The gas turbine blade was studied on the condition that the mainstream velocity was 10m/s and the Renolds number based on the chord length of the blade was 160000.The Hot-film anemometer was used to measure the two-dimension speed distribution along the downstream of the film cooling holes on the suction side and the pressure side. The conclusions are as follows: When the blowing ratio of the suction side and the pressure side increasing, the the mainstream and the jet injection mixing center raising. Entrainment flow occurs at the position where the blade surface with great curvature gradient, simultaneously the mixing flow has a wicked adhere to the wall. The velocity gradient of the u direction that on the suction side increase obviously, also the level of the wall adherence is better than the pressure side. With the x/d increasing, the velocity u that on the pressure side gradually become irregularly, also the secondary flow emerged near the wall region where the curvature is great. The blowing ratio on the suction side has a little influence on velocity v than that on the pressure side.

Numerical Simulation of Particle Axial Mixing in Rotary Kiln

The discrete element code, EDEM, has been employed to simulate the axial mixing of size-binary particles in rotary kiln. Number of contacts has been introduced to track the progress of mixing and number of contacts between different particles has been took as mixing index between different particles to analyze the degree of mixing The results show that the larger velocity of particles in active layer is the main reason for the mixing; axial displacement of smaller particles is due to penetration of smaller particles through the intervals between larger particles.

A Numerical Study on the Characteristics of How Heat and Cooling Transfer on the Leading Edge of a Film-Cooling Blade

In this paper, a numerical simulation was performed to investigate heat transferring characteristics on the leading edge of a blade with three rows of holes of film-cooling using Realizable k- model. Three rows of holes were located on the suction side leading edge stagnation line and the pressure surface. The difference of the cooling efficiency and the heat transfer of the three rows of holes on the suction side and pressure side were analyzed; the heat transfer and film cooling effectiveness distribution in the region of leading edge are expounded under different momentum rations.The results show that under the same condition, the cooling effectiveness on the pressure side is more obvious than the suction side, but the heat transfer is better on the suction side than the pressure side. The stronger momentum rations are more effective cooling than the heat transfer system.

Numerical Simulation of the 1.2MW Wind Turbine Flow-Field

Based on SIMPLE algorithm, with the control equation in finite volume method and the SST K- φturbulence model, 3D models of the 1.2MW wind turbine are built to analyze the relationship between the output power and the pressure, velocity and turbulent kinetic energy of its different sections. The results show that: The change of aerodynamic performance which is caused by the interaction of blades and tower , reduces the available torque of the wind turbine that caused the decreases of the output power. The flow field region affected by central swirl and adhesive vortex is very small. The region of velocity field was affected by the wheel and wind turbine, even a few hundred meters away, but the region affected by wind turbine was smaller than by the wheel.