An experimental investigation of the interaction of swirl flow with partially premixed disk stabilized propane flames

The present work describes the experimental investigation of reacting wakes established through fuel injection and staged premixing with air in an axisymmetric double cavity arrangement, formed along three concentric disks, and stabilized in the downstream vortex region of the afterbody. The burner assembly is operated with a co-flow of swirling air, aerodynamically introduced upstream of the burner exit plane, to allow for the study of the interaction between the resulting partially premixed recirculating afterbody flames with the surrounding swirl. At low swirl the primary afterbody disk stabilizes the partially premixed annular jet in the downstream reacting wake formation region. As swirl increases, a system of two successive vortices emerges along the axis of the developing wake; the primary afterbody vortex is cooperating with an adjacent, swirl induced, central recirculation zone and this combination further promotes turbulent mixing in the hot wake.Complementary measurements of the counterpart isothermal turbulent velocity fields provided important information on the near wake aerodynamics under the interaction of the variable swirl and the double cavity produced annular jet stabilized by the afterbody. Under reacting conditions, measurements of turbulent velocities, temperatures and statistics together with an evaluation of the exhaust emissions were performed using LDV, thin digitally-compensated thermocouples and gas analyzers. A selected number of lean and ultra-lean flames were investigated by regulating the injected fuel and the air supply ratio, while the influence of the variation of the imposed swirl on wake development, flame characteristics and emission performance was documented for constant fuel injections. The differences and similarities between the present partially premixed stabilizer and other types of axisymmetric configurations are also highlighted and discussed.     

Some parameters and conditions defining the efficiency of burners in the destruction of long-lived nuclear wastes

A number of new wordings and statements regarding the targeted problem of destruction of long-lived wastes (transmutation) is considered. Some new criteria concerning the efficiency of a particular burner type are proposed. It is shown that the destruction efficiency of a specific burner is greatly influenced by the prospective time period of the whole destruction process.      

船型体煤粉燃烧器流场的数值模拟

本文将贴体坐标用于具有复杂形状的船型体煤粉燃烧器的三维流场数值模拟中，建立了在贴体坐标下的总体质量校正方程。计算结果令人满意。同时，对存在的问题作了进一步讨论。     

双层多孔介质燃烧器的数值模拟

考虑多孔固体构架的辐射换热以及气固相间的对流换热，引入弥散效应及相间对流换热系数，使用GRI3．0机理和双通量辐射模型，数值求解双层多孔介质内燃烧过程．分析了双层多孔介质燃烧器内火焰稳定性和污染物排放，并与单层的进行比较．结果表明，双层多孔介质燃烧器能够在较宽的流量范围内将火焰稳定在它的交界面附近．     

LES of Jets in Cross Flow and Its Application to a Gas Turbine Burner

LES computations of jets in cross flow (JICF) were performed. Experimental investigations reported in literature are reproduced with good agreement concerning the momentum field and the mixing of a passive scalar. The results validate the ability of the present LES approach to compute fuel injection of the type JICF. LES computations of fuel injection in an industrial gas turbine burner are presented. This revised version was published online in July 2006 with corrections to the Cover Date.     

Influence of Burner Geometry on Heat Transfer Characteristics of Methane/Air Flame Impinging on Flat Surface

An experimental study has been conducted to find the heat transfer characteristics of methane/air flames impinging normally to a flat surface using different burner geometries. The burners used were of nozzle, tube, and orifice type each with a diameter of 10 mm. Due to different exit velocity profiles, the flame structures were different in each case. Because of nearly flat velocity profile, the flame spread was more in case of orifice and nozzle burners as compared to tube burner. Effects of varying the value of Reynolds number (600–2500), equivalence ratio (0.8–1.5) and dimensionless separation distance (0.7–8) on heat transfer characteristics on the flat plate have been investigated for the tube burner. Different flame shapes were observed for different impingement conditions. It has been observed that the heat transfer characteristics were intimately related to flame shapes. Heat transfer characteristics were discussed for the cases when the flame inner reaction cone was far away, just touched, and was intercepted by the plate. Negative heat fluxes at the stagnation point were observed when the inner reaction cone was intercepted by the plate due to impingement of cool un-burnt mixture directly on the surface. Different heat transfer characteristics were observed for different burner geometries with similar operating conditions. In case of tube burner, the maximum heat flux is around the stagnation point and decay is faster in the radial direction. In case of nozzle and orifice burner, the heat transfer distribution is more uniform over the surface.     

Study on methane selective catalytic reduction of NO on Pt/Ce0.67Zr0.33O2 and its application

Monolithic catalysts of Pt/La-Al2O3 and Pt/Ce0.67Zr0.33O2 were prepared to investigate methane selective catalytic reduction (SCR) of NO.The results indicate that Pt/Ce0.67Zr0.33O2 shows high activity and both NO and CH4 can be converted completely at 450 ℃.Meanwhile,NO and CH4 can be converted completely when there exists excess oxygen.The Pt/Ce0.67Zr0.33O2 catalyst were further investigated by using methane as reducing agent to SCR NO in a novel equipment which combined the CH4 selective catalytic reduction of NO with methane combustion.The result shows that the catalyst is high active and the novel equipment is very effective.The conversion of NO is above 92% under the conditions used in this work.The prepared burner and catalysts have great potential for application.     

浓淡燃烧器弯曲圆管内气固两相流动的试验研究

本文运用三维粒了动态分析仪（３Ｄ－ＰＤＡ）对竖直转水平弯管内气固两相流动特性进行了测量，得到了管内气相的速度分布以及颗粒的浓度分布；为进一步改善湾管的浓缩特性，在弯管入口处安装了一三角形滑块，对其管内的颗粒浓度分布也进行了侧量，并记录了弯管两侧的阻力特性。实验结果为人型电站锅炉燃烧器的设计和运行提供了依据。     

Transmutation of radioactive nuclear waste — present status and requirement for the problem-oriented nuclear data base

Transmutation of long-lived actinides and fission products becomes an important issue of the overall nuclear fuel cycle assessment, both for existing and future reactor systems. Reliable nuclear data are required for analysis of associated neutronics. The present paper gives a review of the status of nuclear data analysis focusing on the waste transmutation problem.