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181.
目前尽管国内近海浮标实现了产品化,但深远海尚无定型可靠的深海综合观测浮标系统,基于此,中国科学院海洋研究所设计制作了深海综合观测浮标系统,其浮标体为柱台型结构,采用单点锚泊系留。整个系统主要由浮标体、系留子系统、观测子系统、数据采集处理控制子系统、通信子系统、供电子系统、检测子系统、安全报警子系统和岸基数据接收处理子系统等9部分组成。浮标系统通过搭载不同类型的传感器,实现对风速/风向、气温、相对湿度、气压、能见度、雨量、波浪、表层水温、表层盐度、表层溶解氧、表层叶绿素、表层浊度、剖面流速流向、剖面温盐深(最大深度可达1 000 m)、方位及浮标位置等要素进行实时观测,从而完成对海洋气象、水文和水质等要素的长期、连续、自动监测,并支持铱星和北斗等卫星通信方式,将观测数据实时的传输到岸基数据接收处理系统。近年来,深海综合观测浮标系统在热带西太平洋海域连续进行了4次海上应用,每次应用时间长达1 a。它提供了第一手的大洋上层和海气界面长时间序列的实时连续观测资料,促进了关于气候变化和深海大洋的研究工作。所研制的深海浮标达到目前国际同类产品(美国ATLAS浮标、日本TRITON浮标)的先进水平,并且在水下感应耦合传输等方面进行了创新,形成了自有特色。  相似文献   
182.
为了提高海洋观测研究浮标在位运行的安全性,自主设计了一种北斗/GPS双模定位信标。该信标采用传统的GPS技术进行定位结合“北斗”卫星特有的报文通信和定位功能,通过解决传统GPS信号盲区问题,为中国近海海洋观测研究浮标安全运行提供了更加有力的保障,同时提高了数据保密能力。该系统采用外部供电和内部自主供电相结合的模式,即使外部供电中断,也可保证正常运行不低于1 a,而且基本上不需要对信标进行专门维护,大大降低了运行和维护成本。与该信标配套的岸站管理系统具备发送和短信和邮件报警的功能,可实现浮标运行状态实时监控。  相似文献   
183.
Three archived reanalysis wind vectors at 10 m height in the wind speed range of 2–15 m/s, namely, the second version of the National Centres for Environmental Prediction(NCEP) Climate Forecast System Reanalysis(CFSv2), European Centre for Medium-Range Weather Forecasting Interim Reanalysis(ERA-I) and NCEPDepartment of Energy(DOE) Reanalysis 2(NCEP-2) products, are evaluated by a comparison with the winds measured by moored buoys in coastal regions of the South China Sea(SCS). The buoy data are first quality controlled by extensive techniques that help eliminate degraded measurements. The evaluation results reveal that the CFSv2 wind vectors are most consistent with the buoy winds(with average biases of 0.01 m/s and 1.76°). The ERA-I winds significantly underestimate the buoy wind speed(with an average bias of –1.57 m/s), while the statistical errors in the NCEP-2 wind direction have the largest magnitude. The diagnosis of the reanalysis wind errors shows the residuals of all three reanalysis wind speeds(reanalysis-buoy) decrease with increasing buoy wind speed, suggesting a narrower wind speed range than that of the observations. Moreover, wind direction errors are examined to depend on the magnitude of the wind speed and the wind speed biases. In general, the evaluation of three reanalysis wind products demonstrates that CFSv2 wind vectors are the closest to the winds along the north coast of the SCS and are sufficiently accurate to be used in numerical models.  相似文献   
184.
文中着重介绍为改进浅海环境观测专用浮标和潜标锚泊系统所做的三件工作。一是提高水面标志浮标的抗台风、抗倾覆和抗沉能力以及连接件的流线型化;二是通过理论计算和水池试验,选用抗风能力强的配套的浮标/潜标系统系列;三是应用设计新型的打捞钩,及时而方便地将丢失在海底的仪器等打捞回来。  相似文献   
185.
An accurate numerical prediction of the oceanic upper layer velocity is a demanding requirement for many applications at sea and is a function of several near-surface processes that need to be incorporated in a numerical model. Among them, we assess the effects of vertical resolution, different vertical mixing parameterization (the so-called Generic Length Scale –GLS– set of kε, kω, gen, and the Mellor–Yamada), and surface roughness values on turbulent kinetic energy (k) injection from breaking waves.First, we modified the GLS turbulence closure formulation in the Regional Ocean Modeling System (ROMS) to incorporate the surface flux of turbulent kinetic energy due to wave breaking. Then, we applied the model to idealized test cases, exploring the sensitivity to the above mentioned factors. Last, the model was applied to a realistic situation in the Adriatic Sea driven by numerical meteorological forcings and river discharges. In this case, numerical drifters were released during an intense episode of Bora winds that occurred in mid-February 2003, and their trajectories compared to the displacement of satellite-tracked drifters deployed during the ADRIA02-03 sea-truth campaign.Results indicted that the inclusion of the wave breaking process helps improve the accuracy of the numerical simulations, subject to an increase in the typical value of the surface roughness z0. Specifically, the best performance was obtained using αCH = 56,000 in the Charnok formula, the wave breaking parameterization activated, kε as the turbulence closure model. With these options, the relative error with respect to the average distance of the drifter was about 25% (5.5 km/day). The most sensitive factors in the model were found to be the value of αCH enhanced with respect to a standard value, followed by the adoption of wave breaking parameterization and the particular turbulence closure model selected.  相似文献   
186.
We have investigated the spreading of river water in Suruga Bay by performing numerical experiments and conducting field surveys with drifting buoys. There are clear seasonal variations in the large river discharges into the bay: increased discharge in the rainy summer season and decreased discharge in the dry winter season. The numerical model reproduces the main feature that has been observed in the actual sea: the river water extends gradually from the northwestern to the southeastern regions in the bay, especially in summer. The river water spreading is greatly influenced by the bottom topography of the bay: the Fuji River water spreads over a deep continental slope as a surface-advected plume and extends well offshore, since a large bulge (anticyclonic eddy at the river mouth) extends well offshore and effectively transports the river water offshore. On the other hand, the Oi River water tends to flow parallel to isobaths (along a coastline) on a shallow continental shelf as a bottomadvected plume. Moreover, the influences of seasonal variations in the stratification and a bay-scale, wind-driven circulation are also investigated. Trajectories of the drifting buoys, which were released around the Fuji River mouth, certainly suggest that the bulge exists there.  相似文献   
187.
In this paper, studied are the dynamics of a moored buoy near the surface subjected to wave excitation. According to the physical structure, submersible buoy moored by tethered line is modeled firstly. Then from the differential equations, the natural frequencies are estimated by neglecting the coupling between tangential and normal direction. By use of numerical integration method, solutions are obtained. On this basis, strange attractors and bifurcation phenomena are obtained by applying Poincare map, pha...  相似文献   
188.
锚泊光学浮标浮体设计及近海试验   总被引:1,自引:0,他引:1       下载免费PDF全文
文中设计的光学浮标采用了柱状浮体, 提出了自由旋转的马鞍链结构。理论计算结果表明, 该光学浮标一是初稳性高度大, 二是光学浮标重心位于浮心之下, 浮标的摇摆角较小, 抗倾斜及倾覆能力强。海上试验结果表 明, 对于风力7节、浪高3—4m以下的海况, 浮标倾角≤5°的次数占总采样次数的 54%, 浮标倾角≤10°的次数占总采样次数的83%, 浮标性能较好地满足了水下光辐射测量的技术要求。为减小阴影效应带来的光辐射测量误差, 文中采用了两种解决方法: 一是伸臂结构解决浮标体阴影的影响, 当太阳天顶角为0°时, 在近岸或者清洁水体中浮标体阴影引起的向上辐亮度测量误差分别不大于4% 和1%; 二是光纤光谱仪测量技术减少仪器自阴影的影响, 设计的光谱辐照度和辐亮度光学探头直径均为0.042m, 当水体光束衰减系数为0.12m-1, 太阳天顶角为10°时, 自阴影引起的向上辐亮度测量误差仅为1.5%。  相似文献   
189.
介绍采用谱分析原理提取海浪信息的方法。根据GPS浮标测量得到的海浪高度数据,先通过滑动平均的方法分离海浪信息和潮流潮位信息,然后对海浪信息采用AR模型法进行功率谱估计,并对海浪信息进行连续小波变换,对AR模型法功率谱估计结果和小波变换结果进行综合研究,提取海浪特征参数———周期。最后通过一个GPS浮标试验对上述方法进行了验证。  相似文献   
190.
为解决海洋监测微型传感器供能问题,设计新型波浪能捕获装置,在海面振荡浮筒气室产生空气气柱,驱动介电弹性体形变发电为传感器供能。建立振荡浮子式气柱数值模型,研究新型振荡水柱发电计算理论。利用水动力仿真软件AQWA求解浮子所受波浪力作用振荡幅值、辐射阻尼和附加质量。基于Simulink软件分别计算波浪作用下浮子位移和气室内水柱位移,根据两者的位移差计算气室体积变化所产生的空气压强、介电弹性体发电薄膜形变量和系统输出电能,单次循环周期最大发电量达到24.6 mJ。分析波浪周期、发电薄膜几何参数等对输出电能的影响。  相似文献   
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