负载CuO/Cl活性炭的气态汞脱除特性

为了解CuO/Cl负载对活性炭吸附剂汞脱除特性的影响,开展了利用HCI,Cu(NO_3)_2·3H_2O,Cu(NO_3)_2·3H_2O混合NH_4Cl溶液3种浸渍负栽处理方法获得的活性炭吸附材料汞脱除性能实验研究.汞吸附实验在实验室规模的固态吸附刺汞吸附效能测定系统上进行.结果表明,3种负载改性的活性炭对单质汞的吸附能力均高于原始活性炭,且所获得的汞吸附能力从低到高依次为AC-CuO,AC-HCl,AC-CuO(Cl).活性炭负载CuO/Cl可以使吸附反应器出口处烟气中含有40%以上的二价汞,吸附能力的提高可归因于CuO对活性炭表面汞氧化的催化作用.温度提高有利于催化氧化过程,实际运行工况的最佳温度区间为370～470K.随着SO2浓度的升高,汞吸附能力明显降低.     

高能、高密度烃类燃料对战略飞行器的实用性评论

本文论述了国外烃类燃料的研究与发展,并对高能、高密度烃类燃料在战略飞行器上的实用性作了评论.文中按性能一价格因素权衡了大推力运载火箭助推器以及各军种使用的高效能喷气(涡轮)发动机的巡航导弹在选用高能、高密度烃类燃料中的利弊.     

高密度烃与航空煤油燃烧特性对比试验

采用本生灯方法并结合数字图像处理方法分别对高密度烃和航空煤油的燃烧特性进行了试验研究,分析了不同燃油流量下当量比、预混燃气温度对层流火焰传播速度与贫油点火、熄火极限的影响,从而确定了高密度烃的层流火焰传播特性。实验研究表明:当量比为1.1时,高密度烃层流火焰传播速度达到最大值,而航空煤油在当量比为1时达到最大值,且在相同工况下高密度烃的层流火焰传播速度的最大值较小;层流火焰传播速度随混合气温度的增加而变大;燃油流量的改变对层流火焰传播速度的影响不大;相同工况下高密度烃的贫油点火、熄火极限比航空煤油的要大,且燃油流量在小于35ml/h区域内,贫油点火极限、熄火极限的当量比,都随燃油流量的变化都存在一定的波动。     

气态巨星的另类世界

最近几个月,"卡西尼"号探测器围绕土星旋转的卫星拍摄了许多精美的照片.从传送回来的图片来看,土星与它的卫星就仿佛是热气球周围飘浮着许多颗粒.     

Radical recombination in a hydrocarbon-fueled scramjet nozzle

To reveal the radical recombination process in the scramjet nozzle flow and study the effects of various factors of the recombination, weighted essentially non-oscillatory(WENO)schemes are applied to solve the decoupled two-dimensional Euler equations with chemical reactions to simulate the hydrocarbon-fueled scramjet nozzle flow. The accuracy of the numerical method is verified with the measurements obtained by a shock tunnel experiment. The overall model length is nearly 0.5 m, with inlet static temperatures ranging from 2000 K to 3000 K, inlet static pressures ranging from 75 k Pa to 175 k Pa, and inlet Mach numbers of 2.0 ± 0.4 are involved.The fraction Damkohler number is defined as functions of static temperature and pressure to analyze the radical recombination progresses. Preliminary results indicate that the energy releasing process depends on different chemical reaction processes and species group contributions. In hydrocarbon-fueled scramjet nozzle flow, reactions with H have the greatest contribution during the chemical equilibrium shift. The contrast and analysis of the simulation results show that the radical recombination processes influenced by inflow conditions and nozzle scales are consistent with Damkohler numbers and potential dissociation energy release. The increase of inlet static temperature improves both of them, thus making the chemical non-equilibrium effects on the nozzle performance more significant. While the increase of inlet static pressure improves the former one and reduces the latter, it exerts little influence on the chemical non-equilibrium effects.     

富氧预燃室高压缩尺试验研究

为满足液氧／煤油发动机推力大范围变化和预燃室要在大范围工况条件下工作的要求，采用带缩进长度和二次喷注的双组元离心式喷注单元，对富氧预燃室进行了高压缩尺试验研究。头部二次喷注孔为矩形和圆形、身部4种不同长度的6台试验件的试验结果表明，缩尺试验的最好温度均匀性≤50℃，燃气平均停留时间为10ms左右，矩形和圆形喷注方案的缩进室混合比分别小于20和24时可以避免产生低频不稳定燃烧。所得结论可用于液氧／煤油发动机的研制，并对新型发动机的研制具有一定的借鉴作用。