On the use of laboratory ocean circulation models to simulate mesoscale (10–100 km) spreading

The development of hydrodynamic numerical models for environmental studies depends on good benchmarks to calibrate and validate the physics and numerical codes. Laboratory models of non-linear and coupled physics in topography for which no analytical solutions are available can provide such valuable benchmarks. Although field data are necessary for a final validation, they are often of less value for developing numerical models, since a truly synoptic coverage of a scenario is seldom found, knowledge of the forcing conditions is imperfect and average conditions of a non-linear system are seldom obtained by applying average boundary conditions.The role of laboratory models and experiments for providing information on turbulence in complicated topography is indisputable. The high topographical resolution of these models reveals how narrow and filamentous many of the flow features can be, as often seen in satellite images. Such filaments enhance diffusion through a process known as shear dispersion. The filaments are also of concern for the interpretation of sparse field measurements and for computing the mesoscale (10–100 km) spreading characteristics. Time histories of dye clouds and clusters of particles in laboratory simulations of ocean currents, without wind, show much larger spreading than particle spreading due to strong winds. The results demonstrate that numerical models need high resolution and/or good parametrization of the spreading characteristics, which vary both in space and time, to achieve their goals. It is proposed that the differences between numerical and laboratory simulations of dispersion, with identical forcing, be parametrized as a size-dependent, or time-dependent random walk diffusion in the numerical code.The laboratory results amply show that spreading is greatly enhanced by shear dispersion, and that assessments of the consequences of accidental oil spills or releases of radionuclides, for example, must take this into account. Island communities in tidally active regions are particularly prone to the consequences of a rapid dispersion of contaminants.     

循环流化床锅炉技术发展共识之处

国内外研发CFB锅炉技术已走过30多年历程,经过不断地改进、完善,CFB锅炉技术已趋成熟。先进的CFB锅炉技术已得到共识,这为今后设计、制造、使用CFB锅炉的单位和从事CFB锅炉研发的工程技术人员提供了宝贵的经验。     

循环旋风分离器内气液两相流动数值模拟

采用雷诺应力模型RSM对循环旋风分离器内气液两相流动的情况进行了数值模拟研究,讨论了循环旋风分离器内切向速度、轴向速度、径向速度、压力场、雷诺应力的分布特点以及相同入口速度下分离器内液滴运动轨迹与分离器的分离效率。数值模拟结果表明,循环旋风分离器切向速度呈现明显的驼峰状,轴向速度上行流和下行流明显,径向速度相对较小,压力由轴心向外逐渐升高,雷诺应力分布复杂且无明显规律,分离器对小直径液滴分离效率较低,入口速度对分离效率的影响比较明显。     

EFFECT OF OPERATING VARIABLES ON BED TO WALL HEAT TRANSFER IN A CIRCULATING FLUIDIZED BED

Heat transfer coefficients were measured for 227 and 87 micron size particles of silica sand in a 102 mm dia. and 5.5 m tall circulating fluidized bed made of plexiglass. Effects of solid circulation rate, fluidization velocity, bed density and particle sizes were studied. The heat transfer coefficients were calculated from the temperatures measured along the axis of a 25 mm dia 100 mm long cylindrical heat flux meter.     

一种可固化防漏工作液水化机理研究

研究了一种低密度（1.30 g/cm3）可固化防漏工作液,用于解决低压易漏失井段在固井时,因地层承压能力低、易漏失、窜槽,导致固井质量不高的问题。通过在优质的隔离液中加入一种具有固化性能的材料（2.60~2.90 g/cm3）替代常规的加重剂,配制一种低密度可固化工作液。该工作液能有效平衡地层压力并在环空中固化,从而对易漏地层起到防漏效果、提高固井质量。重点分析了该体系的固化后试样强度及水化机理,研究发现:工作液固化强度发展的实质是OH-对固化剂玻璃体结构的破坏;通过对配方的调节能实现从30~90℃固化试样都具备一定的抗压强度。该体系的研发对于防漏工作液的设计提供了一种新的思路,同时还可以运用于钻井工程中堵漏,提高地层的承压能力。      

Parallel Domain-decomposed Taiwan Multi-scale Community Ocean Model (PD-TIMCOM)

The Parallel Domain-decomposed Taiwan Multi-scale Community Ocean Model (PD-TIMCOM) was developed to provide a flexible and efficient community ocean model for simulating a variety of idealized and real ocean flows over a wide range of scales and boundary conditions. The model is particularly targeted at resolving multi-scale dynamics in the ocean environment, ranging from small scale turbulence to the global circulation gyres. The novel parallel algorithm improves the efficiency of the Error Vector Propagating (EVP) method, a simple direct solver for the typical pressure Poisson equations in the PD-TIMCOM. The new approach is ideal for multiple processes and takes advantage of parallel domain-decomposition, which can significantly reduce the operational counts and computational costs simultaneously. The speed-up is proportional to the number of domains, thus making the PD-TIMCOM a practical eddy-resolving global ocean model for climate projection. We illustrate the parallel performance based on the 1/4° global adaptation of PD-TIMCOM. Our results show accurate meso-scale variability, the reasonable separation of several western boundary currents from the coast, and the appropriate watermass distribution in the global ocean. Consistent with satellite altimetry, the results also show clear mean fronts in the Kuroshio Extension and extensive Kuroshio–Oyashio interaction. This leads to a quasi-equilibrium eddy field associated with three meandering jets in the Kuroshio Extension and Gulf Stream.     

从皇城到投资者的城市—北京城的扩展与建设

北京具有2000多年的城市历史，留下许多层面的城市结构和建筑类型，目前，北京城的心脏依然是故宫，而且老城的几何秩序似乎仍然主宰着整个大都市，作为13亿人民的政治和文化中心的北京，正寻找着能够充分体现现代化成就和中国特色的建筑风格，北京也同样必须作出巨大的努力，来解决实现了房屋，基本设施和环境问题，最后，北京需要一个区域性发展的新概念，来控制城市的动态扩张。     

影响文中—文东油田钻井安全的地质因素及对策

高采出程度、高压注水和井况恶化,导致井漏、井涌、出水,影响钻井安全。非均质断块油田开发中后期容易出现的井漏、井涌出水问题,可综合运用邻井钻井、测井和注采生产动态资料,通过先期堵漏和使用高强复合堵漏剂、循环排气逐步加重和相邻注水井停注泄压等措施予以解决。     

建立商品需求供给流通模型的设想

本文基于自然界广泛存在的平衡原理,给出了商品的需求供给流通模型,并讨论了其基本特性.对不同地区或具体的某种商品,仅需对个别方程进行适当修改或调整,其模型仍可适应.     

带固体循环气流干燥器系统停留时间分布的计算

就具有固体循环系统的气流干燥器停留时间分布规律进行了理论研究,提出了停留时间分布密度的计算公式,通过电算,得出了在不同的循环比下停留时间分布的计算结果。