Papers by Author: Jun Rui Shi

Abstract: The widely used technologies of Selective Catalytic Reduction (SCR), Non-selective Catalytic Reduction (SNCR) and hybrid SNCR-SCR for coal-fired boiler in China are reviewed. The technical characteristics of different processes and transformation methods are compared. Analysis is made about the advantages of each technology and the major problems in the retrofitting. The proposal for the corresponding problems is presented. Reference is provided for coal-fired boiler denitrification transformation in China.

Abstract: Diffusion filtration combustion attains widely attention as its small volume, compact structure, large power range and less emissions which is very important for saving energy in recent years. It is the combustion that fuel and oxidant are separated before burning in porous media. The researches about diffusion filtration combustion are summarized the theory, experiment and numerical simulation in this paper. There is still much knowledge unknown which should be worked on.

Abstract: Two-dimensional numerical investigations on the performance and structure improvement of a inert porous media burner with reciprocating flow are presented. An improved burner design is proposed and this leads to a wider high temperature profile and moderate pressure loss for extremely dilute CH4/air mixture with an equivalence ratio of 0.1.

Abstract: This paper experimentally study on CH₄ / air co-flow diffusion combustion on the upper surface of porous media packed beds. The flame height and flame shape were reconstructed from the upper and the side of the combustor. The influence of the height of the packed bed on the flame height and flame shape is reported. It is shown that the flame height decreases rapidly and the circular diameter increases rapidly with increase the height of the packed beds.

Abstract: Abstract. temperature and species distributions of an atmosphere coflow laminar CH₄/air diffusion flame was studied by numerical simulation. We solve the steady equations for the species mass fraction, energy, momentum with detailed gas-phase reaction mechanism and complex thermal and transport properties to predict the velocity, temperature, species distributions for different dilute level. Results indicated that the predicted temperature and species are in excellent with available experiment date at different dilute level. In addition, it is indicated that adding N₂ in the fuel has a significant influence on the flame temperature and species distribution.

Abstract: Abstract: Based on the idea of residual heat recovery by porous media, the article illustrates the process how the heat transmitted to the targeted porous media via intermediate after the residual heat from flue gas storing in the porous media. The primary air is preheated via the porous media. The article analyzed the energy saving characteristics of the gas cooker from the perspective of experiment and the numerical calculation.

Abstract: Aluminum foams, as a representative of metallic foams, are a kind of very useful and promising functional materials. This paper reports progress in three-dimensional numerical simulations of gas bubble-metallic melt turbulent flows during the foaming process of aluminum foams, in which air is injected into molten aluminum composites and the melt is mechanical stirred by a pitched-blade impeller with an inclined shaft. The bubble-melt two phase flow in the tank is described with an Eulerian-Eulerian two fluid model, the impeller flow region is simulated based on the Multiple Reference Frames (MRF) method. Influences of gas flow rate, impeller rotation speed and initial bubble diameter on the characteristics of the liquid flow field and gas fraction distribution are examined. Computational results show that bubbles tend to accumulate behind the impeller blades and have an approximately uniform distribution near the top surface of the liquid. Gas holdup values are increased with increasing the impeller speed and gas flow rate and decreased with the bubble diameter.

Abstract: In this paper, based on the theoretical analysis and reasonable simplification, one-dimensional mathematical model is presented for the counter-current oxidation of ventilation air methane. The process of counter-current oxidation reaction is simulated by applying the computational fluid dynamics (CFD) software (Fluent), and the effect of the dominating working parameters (such as flow velocity and equivalence ratio and half cycle) are discussed on the temperature and rate of reaction within the counter-current oxidation reaction. The distribution of the temperature field and the reaction rate are simulated when half cycle is 30s, the equivalence ratio is 0.2 and the velocity 0.06 m/s, 0.1m/s and 0.2 m/s. The combustion characteristics are summarized for the device of counter-current oxidation reaction, and the effects of working parameters are analyzed on the burning characteristics. It is so important to increase the combustion efficiency and energy utilization.