近岸较大区域波浪数值模型的比较

将适用于近岸较大区域波浪传播变形的三种模型,即基于抛物型缓坡方程的不规则波模型、引入浅水波浪谱 TMA 谱的 SWAN(simulating waves nearshore)模型以及采用默认 JONSWAP 谱的 SWAN模型应用于特拉华大学(University of Delaware)圆形浅滩实验进行比较.结果显示,抛物型缓坡方程和SWAN 的模拟结果与实验所测数据符合都比较好; SWAN 在非线性作用较强的浅滩中心及靠后部效果更佳,而抛物型缓坡方程由于没有考虑非线性作用,模拟得到的最大波高较实测值偏高,且波高变化较为剧烈.     

潮汐和流影响下长江口波浪场数值计算

采用SWAN模型和REF/DIF模型进行嵌套计算的方法来获取长江口海域实际波浪场.其中设计一种根据入射波向即时生成计算网格的方法,解决REF/DIF模型对于波浪入射角的限制从而实现两种模型的嵌套.为考虑水流和潮位分布的空间差异对波浪传播变形的作用,利用二维流场模型计算长江口的水位和流场过程,在实际波浪计算中引入了水位和水流作用.计算结果与观测资料的对比表明:1)SWAN模型和REF/DIF模型的嵌套计算方法可以作为提高浅水区域波浪计算精度的一种有效途径;2)水位和水流对长江口波浪计算的影响显著,考虑了水位和水流条件后,尤其是在大潮期间,能比较显著地提高计算精度.     

考虑边界波浪方向的缓坡方程自适应求解模型

缓坡方程是描述近岸波浪运动较好的数学模型之一。在发展的自适应有限元求解缓坡方程的基础上,采用迭代求解的方法,确定波浪相对于边界的入射方向,从而对边界条件进行改进,建立了求解缓坡方程的数值计算模型。典型算例表明,考虑波浪相对于边界的入射角度后,模型可以更好地模拟吸收波浪边界,同时对多向波对双突堤的绕射进行了模拟研究,与试验结果比较表明,所建立的数值计算模型能够适用于多向不规则波传播过程的模拟研究。     

多向不规则波浪作用下群墩结构上爬高的计算研究

波浪的方向分布对波浪的传播及其与工程结构物的作用都具有明显影响,目前现有的研究大多是基于单向波浪进行的。为了研究方向分布对群墩结构上的爬高影响,基于规则波浪与群墩作用的理论解,结合多向不规则波浪的造波方法,建立了多向不规则波浪与群墩作用的计算模型,同时进行了物理模型试验对模型的有效性进行了验证。系统地对群墩周围及表面上的波浪爬高进行了计算分析,结果表明,方向分布对波浪爬高具有较大的影响,且不同位置处的影响并不相同,在实际的工程设计中如果按照单向波浪计算,可能低估或者高估群墩周围的爬高。     

长江口附近海域台风浪的数值模拟--以鹿沙台风和森拉克台风为例

利用SWAN波浪模型计算长江口附近海域的台风浪,鉴于长江河口岸界和地形复杂,拟采用曲线网格.为证实曲线网格下的SWAN模型对于复杂地形的有效性,首先选用美国特拉华大学波浪水池实验资料对SWAN模型进行检验,结果表明利用曲线网格能不过多增加计算量而提高关键区域的计算精度.以0215号鹿沙台风和0216号森拉克台风为例,将SWAN模型应用到长江口附近海域,进行台风浪的数值模拟.通过浮标测站实测资料验证,表明有效波高计算值与实测值符合良好.通过综合分析模型计算的波浪场,说明SWAN模型能合理地反映长江口附近海域台风浪的分布.     

多向不规则波浪生成的数值方法

实际的海浪是三维(多方向)的,海浪的方向分布对于海浪折射、绕射及泥沙运动等的研究具有重要的意义,因而人们利用多向不规则造波机对它进行物理模型试验研究.同时,基于合适的数学模型,可在计算机上产生长时段的多向不规则波浪,用于研究海浪的基本特性及其对工程建筑物的作用,也是一种方便经济有效的手段,这也是制作多向不规则波造波机控制信号的基础.因此,如何由数模有效地合成多向不规则波浪,日益受到人们的重视.常用的一种方法是把海浪看作由无数不同频率和不同方向的组成波线性叠加而成,因而将模拟二维波浪的方法[1]直接推广应用于三维波浪的模拟.但是这样模拟所得的波浪往往是空间上不均匀,时间上会重复出现,需要进一步研究改进.本文首先给出了多向不规则波的三种模拟方法,并对其模拟结果进行了分析检验,给出了较理想的海浪模式.在此基础上,研究了模拟所得波浪的基本特征和模拟参数的确定.     

多向不规则波浪的确定性模拟

波浪波动时间过程及波列的模拟,对于开展实际波浪对于工程建筑物的作用具有重要的意义。本文采用线性叠加的单叠加模型,建立了多向不规则波浪的确定性模拟方法。基于理论模拟的规则波、单向不规则波和多向不规则波,验证了波浪确定性模拟方法的有效性。定性地对比分析了模拟波列和已知波列的一致性;定量地研究了模拟波浪在空间范围rr/L_s的误差分布情况(rr表示指定位置与给定位置的空间距离,L_s为有效波长)。并且建议,采用本文方法进行波浪确定性模拟时,最佳的浪高仪间距应小于0.12L_s。     

斜向和多向不规则波在斜坡堤上的平均越浪量的试验研究

通过三维物理模型试验研究了在斜坡堤上斜向和多向不规则波在非破碎条件下的平均越浪量与波浪参数及堤参数的关系.着重考察了波浪以小角度(0°~30°)斜向入射时平均越浪量的变化情况,肯定了多向波的越浪量在这一范围内有所谓“小角度斜向增加”的现象,但否定了单向波也具有这一现象.在考察波浪的方向分布影响时发现波浪斜向入射时多向波的越浪量往往要比单向波的大.比较了已有的相关研究成果,给出了适用于混凝土护面和扭工字块体护面斜坡堤上斜向和多向不规则波的平均越浪量的估算公式.     

斜坡上波浪破碎与越浪非静压数值模拟

为合理确定防浪建筑物的越浪量,基于含非静水压力梯度项的非线性浅水方程建立了近岸波浪越浪数值模型。通过采用域内造波、消波并结合波前静压假定的破碎模型,模拟了规则波和不规则波在斜坡上的波浪传播变形,并在此基础上进行了越浪量数值计算。数值计算结果与物理模型实验结果表明,非静压模型可合理地描述波浪破碎点位置、破碎后的波高、增减水以及斜坡上的堤后越浪量。数值模型具有较高的计算精度和计算效率,可为实际工程防浪建筑物越浪以及堤顶高程的设计提供一种新的数值研究手段。     

长江口深水航道工程对航道附近海域波浪分布特征的影响研究

本文针对长江口深水航道工程建设前后航道内波浪特征的变化进行了分析研究,首先基于对长江口历史波浪资料分析,确定了E、NE和SE3个浪向为航道内典型代表,采用第3代波浪模型SWAN对工程建设前后的波浪进行模拟计算。研究表明,航道工程建设后航道内的有效波高和周期明显减小,但是其变化的规律基本一致。在不同天文潮影响时,航道内的有效波高和周期大不相同。E向和NE向的浪在大潮期间有效波高和周期均高于小潮时,SE向浪却相反。对于NE向的浪,航道工程对有效波高的影响大致呈现出从右向左逐渐减弱。对于E向和SE向的浪,航道工程对有效波高的影响大致呈现出从右向左先增强再减弱。航道工程对不同方向的浪在不同分段上也有所不同,在右段对NE向的消弱最强,对SE向最弱,在中段和左段对E向消弱最强,对NE向最弱。航道内流场与水位对波要素的影响也略有差别。     

Model of the post-Cenozoic evolution of the cryolithozone of the shelf of the western part of the Laptev Sea

The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ～200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ～380 km from the coast at a depth of ～250 m above the sea level.     

Investigation of the mechanism of the long-term evolution of the carbon cycle in the ecosystem of the Sevastopol bay

We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.     

Contemporary state of the investigation of the influence of the discharge of rivers on the hydrologic structure of the Black Sea

We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

双壳贝类血淋巴中儿茶酚胺的检测方法初步研究

研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。     

Modelling of the ecosystem of the Black-Sea shelf zone near the estuary of the Danube

We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

The influence of the bottom contour on the deformed state of the ice cover due to the motion of the submarine

The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared.     

黄河入海径流对河口海域盐度影响研究

为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明：黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km²,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km²;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。     

Dynamics of the ice cover and peculiarities of the ice transportation of the sediments at the tidal flats of the Kandalaksha Gulf of the White Sea

Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m³ from 1 km of coast in the wide tidal flats and <50 m³ on the steep coasts) are delivered to the water area.     

Relationship between the path of the Kuroshio in the south of Japan and the path of the Kuroshio Extension in the east

A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.     

国产XBT海上比测方法研究及结果分析

随着国产投弃式温深仪(XBT)性能的提高,其使用范围和规模也逐步扩大,受某专项办的委托,厦门大学在南海东北部开展了"海洋监测设备适用性检验规范及海上试验研究(国家863计划)"项目,针对海洋技术领域研发的技术较为成熟、具备产品化条件的XBT开展检验与验证,对国产XBT的性能和实际使用情况进行分析和总结。试验中,在不同站点进行温盐深仪(CTD)现场测量,以此数据为真值对国产和进口XBT精度做评估。在较高速度走航测量时,则以进口XBT数据为参照,对国产XBT进行评估。试验结果表明,国产XBT整体上表现良好,成功率大概为80%,有些型号的国产XBT精度与进口XBT精度接近,但国产XBT无效剖面较多。同时也发现,进口XBT的精度无法满足预期比测的要求,不能准确计算出国产XBT精度,但结果仍然具有参考价值。本次试验可以为国产XBT的规模化应用和推广提供数据支持,也可为其他型号XBT/XCTD/CTD等仪器的比测提供借鉴。