Finite Element Analysis to Two-Dimensional Nonlinear Sloshing Problems

A two-dimensional nonlinear sloshing problem is analyzed by means of the fully nonlinear theory and time domain second order theory of water waves. Liquid sloshing in a rectangular container subjected to a horizontal excitation is sim-ulated by the finite element method. Comparisons between the two theories are made based on their numerical results, It is found that good agreement is obtained for the case of small amplitude oscillation and obvious differences occur for large amplitude excitation. Even though, the second order solution can still exhibit typical nonlinear features of nonlinear wave and can be used instead of the fully nonlinear theory.     

规则波作用下圆形调谐液体阻尼器的试验研究

对规则波作用下圆形调谐液体阻尼器的可行性及有效性进行了试验研究，探索调谐液体阻尼器对于固定式海洋平台结构成振的实用性。调谐液体阻尼器的减振性能通过结构响应的减小程度来评价。试验观测了容器中液体的运动形态，同时考虑容器的大小、数目，阻尼器与平台结构、波浪三者之间的频率比，质量比以及激振波浪参数等诸多因素的影响，得到了利用调谐液体阻尼器进行固定式海洋平台减振设计的具有指导意义的结论。     

Remolded Undrained Strength of Soils

1 .ＩｎｔｒｏｄｕｃｔｉｏｎＭａｎｙｒｅｓｅａｒｃｈｅｒｓｈａｖｅｉｌｌｕｓｔｒａｔｅｄｔｈａｔｔｈｅｓｏｆｔｍａｒｉｎｅｃｌａｙｅｙｓｏｉｌｓｇｅｎｅｒａｌｌｙｓｈｏｗｔｈｅｏｖｅｒｃｏｎｓｏｌｉ ｄａｔｉｏｎｒａｔｉｏｂｅｉｎｇｌａｒｇｅｒｔｈａｎｕｎｉｔｙ ,ａｌｔｈｏｕｇｈｔｈｅｓｉｔｅｇｅｏｌｏｇｙｉｎｄｉｃａｔｅｓｎｏｒｍａｌｃｏｎｓｏｌｉｄａｔｉｏｎ (ｅ .ｇ .,Ｚｈａｎｇｅｔａｌ.,1 995;ＨｏｎｇａｎｄＴｓｕｃｈｉｄａ ,1 999) .Ｂｕｒｌａｎｄ (1 990 )ｉｌｌｕｓｔｒａｔｅｄｔｈａｔｔｈｅｍ…     

Study on the dynamic characteristic of a U-type tuned liquid damper

By means of Lagrange's equation, the “coupled” equations of motion for a horizontal plate carrying a U-type tuned liquid damper (TLD) are derived. The “uncoupled” equations of motion for the liquid (in the TLD) and the structural system are then obtained by decoupling the “coupled” ones. Unlike the existing literature to indirectly determine the natural frequencies of a damped vibrating system by using the resonant method, the “complex” eigenvalues of the coupled damped system are obtained directly from the associated eigenvalue equations. Besides, the pressure intensities in the two air chambers and the sizes of the two vertical tanks together with the horizontal conduit are arbitrary in the formulation of this paper. The influence of some key parameters of the TLD on the dynamic responses of the structural system is studied.     

Critical State Sedimentation Line of Soft Marine Clays

The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative assessment of such effects is not possible because of unavailability of the formula for the compression curve of marine sediments responsible for unit sensitivity. In this study, the relationship between the remolded state and the conventional critical state line is presented in the deviator stress versus mean effective stress plot. The analysis indicates that the remolded state is on the conventional critical state line obtained at a relatively small strain. Thus, a unique critical state sedimentation line for marine sediments of unit sensitivity is proposed. The comparison between the critical state sedimentation line proposed in this study and the existing normalized consolidation curves obtained from conventional oedometer tests on remolded soils or reconstituted soils explains well the     

竖直螺旋槽管强化传热传质特性的研究—壁面几何形状对液膜流动特性的影响

该文研究竖直螺旋槽管壁面液膜形成及流动特性。建立了单组分流体的物理和数学模型并得出解析解 ,并分析了壁面几何形状对液膜流动特性的影响。结果表明 :液膜的形状主要受表面张力影响 ,在表面内弯处液膜较厚 ,而在槽道起始部液膜较薄。相对于光滑直管 ,竖直螺旋槽管壁面液膜具有均匀的厚度分布和更好的传热传质性质。     

HPLC柱前衍生法测定海水中溶解态游离氨基酸

本文采用反相高效液相色谱法测定海水中溶解态游离氨基酸,整个分析过程只需40 min就可使所有海水样品中的氨基酸得到很好分离,对各含6pmol的16种氨基酸混合样分析偏差在10%左右,检测极限为100fmo1,线性范围在1pmol到Inmol之间。     

海藻液体肥肥效的研究

采用由碱解法和酶解法制得的海藻液体肥 ,在蔬菜作物上进行浸种和叶面喷施试验 ,结果表明 :海藻液体肥能显著提高种子的发芽率 ,促进作物的生长发育 ,提高作物产量。用海藻液体肥浸种 ,可使种子的发芽率提高 1 0 %左右 ,将其用于叶面喷施 ,则可使作物增产 1 0 %～2 0 %。     

Parameter estimation and simulation of dependence of constant pressure batch dewatering on initial solids concentration

The problem of predicting dependence of constant pressure batch dewatering of particulate suspensions on feed solids concentration is considered. Scaling transformations which demonstrate that evolution in the cake consolidation stage of dewatering is governed by an underlying self-similar behavior are proposed. The self-similar master curve, which can be obtained using only one set of experimental dewatering data obtained with a feed suspension having solids concentration above the gel point, is employed for estimating dependence of key dewatering process parameters on feed solids concentration. Using the parameter estimates in a Darcy's law based dewatering model, it is shown that the complete evolution of dewatering for a desired feed solids concentration can be predicted with reasonable accuracy. The approach is simpler to implement in comparison to available pressure filtration models, which require several suspension characterization experiments.     

对混合土液塑限试验的讨论

土的液塑限试验是土工试验常见试验之一。含有一定数量粗粒组的混合土,用0.5 mm以下粒径范围的土作液塑限试验,得到的液塑限偏低,由此土的分类定名不符合实际。建议用0.075 mm以下粒径范围的土做液塑限试验。