复杂构造中地震波传播数值模拟

波动方程数值模拟是研究地震波传播特征的有效手段。从非均匀弹性各向同性介质中的波动方程出发, 研究发展了伪谱法数值模拟方法, 并给出了稳定性条件。用该方法对一个实际复杂构造模型进行模拟, 得到了较高精度的单炮记录, 且波场特征丰富, 表明本模拟方法是研究复杂地质构造中地震波传播特征的一种有效方法。     

准噶尔盆地车排子地区新近系沙湾组层序地层

综合车排子地区新近系沙湾组钻井、测井及地震资料, 将沙湾组划分为二套三级层序。不整合面作为沙湾组的层序界面, 主要从地震剖面和钻井剖面来识别。体系域划分的关键是根据地层上下叠置样式的变化、岩性、测井曲线来确定最大湖泛面的位置。研究区构造为一大型的斜坡, 见不到明显的坡折带, 因此可以建立起无陆架坡折的缓坡盆地层序地层模型。在单一的构造格局控制下,沉积物供应速率、气候和湖平面变化控制了沙湾组层序的发育。结合车89 井、车95 井出油层位的特点, 利用层序地层基本理论, 预测了有利的储盖组合区。     

CO2 emission trading within the European Union and Annex B countries: the cement industry case

The cement industry is the third largest carbon emitting industrial sector in the EU. This article presents the foreseeable technological evolution of the cement industry under business as usual circumstances, and examines the effects on the sector of carbon trading. For those purposes a global dynamic simulation model of the cement industry (CEMSIM) has been developed. The model is composed of a series of interconnected modules on cement consumption and production, international trade and capacity planning. This study quantifies the benefits achieved from emission trading in different markets (EU15, EU27 and Annex B), derived both from the revenues of emission trading, and from the lower compliance costs. The magnitude of the potential carbon leakage effect is also assessed.     

Time stepping finite element analysis of a variable speed synchronous generator with rectifier

Several applications for renewable energy conversion make use of variable speed generators. A conversion from variable frequency to grid frequency is therefore essential. One part of the converter is a rectifier. A rectifier model is presented, which is integrated in a time stepping finite element simulation environment where the generator and circuit equations are solved simultaneously. The model handles bidirectional alternator speeds as the application is a linear generator for ocean wave energy conversion. The rectifier model is extended with a load model, consisting of R, L and E, and simulations show what impact the rectifier has on the generator’s behaviour.     

Theoretical and experimental studies on low-temperature adsorption drying of fresh ginger

The working principle of low-temperature adsorption drying and the advantages of its application for biological materials drying were introduced in this paper. By using fresh ginger as the drying material, the effects of temperature and relative humidity on its drying characteristics were examined. The results show that the drying rate increases with the temperature increasing or the humidity decreasing. The drying time to the equilibrium is almost the same under different humidity conditions, but low equilibrium moisture content can be acquired under low humidity. The shrinkage characteristics of fresh ginger were also studied. The change of its surface appearance during the drying process was characterized by the new Charged Coupled Device (CCD) and the Environmental Scanning Electron Microscopy (ESEM) technique. A mathematical model of drying dynamics was set up according to the experiments.     

Numerical investigation of boiling flow of nitrogen in a vertical tube using the two-fluid model

The two-fluid model has been extensively used in modeling boiling flow of water, however, there are few equivalent studies of boiling flow of cryogenic liquids. In the present study, the two-fluid model which is basically included in the CFX code was modified by incorporating new closure correlations, then boiling flow of liquid nitrogen in a vertical tube was numerically simulated using the basic model and the modified model, respectively. Comparison with experimental data shows that the modified model is satisfactorily improved in accuracy. This study demonstrated that the following parameters and models are important for accurate prediction: the lift force, the bubble diameter distribution and the active site density, among which, the active site density has the most significant effect.     

关于空冷机组容量、参数选择的若干意见

将结合我国国情、电网调度、气象条件、给水泵匹配等方面,对目前我国空冷发电厂的机组容量、参数选择的若干有关外部影响条件及机炉容量匹配等进行分析,并提出相应的建议。     

焚烧过程中氯对重金属形态的影响及脱氯特性研究

目前我国国内还普遍缺乏对危险废弃物焚烧处理的机理研究，尤其是焚烧过程中关于氯、重金属排放及二者之间关系的基础研究。从这一点出发，着重研究了典型危险废弃物之一染料残渣在小型管式炉中焚烧过程中氯化氢的排放特性；并利用化学热力学平衡方法计算了焚烧过程中氯元素对多种常见重金属的排放影响；初步研究了在利用回转窑处理危险废弃物时，两种脱氯剂对烟气中氯的脱除效果。     

支持向量机回归模型在径流预测中的应用

为了探索提高径流中长期预测精度的有效途径,尝试建立了基于支持向量机的径流预测模型,并应用于西江流域梧州站的年、月径流预测中,取得了很好的效果。并与神经网络预测进行对比,结果表明该模型的预测精度要高于人工神经网络模型。     

不同型式流场的PEMFC内部传质分析

对采用不同型式流场的PEMFC进行建模,并用控制容积法对控制方程进行离散,求解得到PEMFC内部各物理量的分布以及综合水拖带系数、质子交换膜平均电导率等。分析了采用交趾型流场和常规流场时PEMFC的内部传质以及阴极性能、电池性能和膜性能,结果认为采用交趾型流场时,PEMFC阴极性能高于采用常规流场的PEMFC阴极性能,但质子交换膜的平均电导率低于采用常规流场时。在没有液态水产生时常规流场PEMFC性能高于交趾型流场PEMFC。