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1.
抛弃式温盐探头运动状态的数值模拟及其实验验证   总被引:4,自引:0,他引:4  
抛弃式海水温盐探头用于快速获取海洋温度、盐度剖面资料。探头投放后运动时间和路程关系的确定将直接影响剖面结果的准确性。本文重点分析了探头运动特性,其中包括探头入水速度损失、运动阻力系数等运动参数,同时分析了探头运动过程中质量改变与海水密度不同对其运动规律的影响,最终得到探头下落距离和时间的关系。通过与实测结果比较及分析,证明了计算方法及其结果的合理性和准确性。  相似文献   

2.
针对多波束测量中存在的声速误差问题,探讨了声速误差对多波束测量的影响以及影响表层声速和换能器动态吃水深度变化的主要因素,提出了一种旨在提高多波束测量精度的有效手段——温、盐、深探头的综合运用,以便实时测定表层海水的声速和换能器的动态深度吃水改正。  相似文献   

3.
对台湾海峡南部海区1997年8月的CTD资料进行了温、盐垂直结构分析.结果表明:大部分调查海域存在温、盐跃层;台湾浅滩南部和东南部海域的温、盐垂直结构较为复杂,这与多种水系在此交汇有关,但下层海水的低温高盐特性仍表明这一海域是上升流区;泉州外海的下层存在低温高盐海水的爬升,但没有影响到表层.  相似文献   

4.
本文以渤海湾为例,运用MIKE3 FM数值模拟软件建立了渤海湾天津附近海域海水淡化浓海水与电厂温排水混合排放温盐扩散三维数值模型,开展了浓海水和温排水不同混合比例温盐扩散对比研究。研究结果表明:浓海水与温排水混合排放可以使受纳海域盐升范围显著减小,并且混合比例越高,效果越明显。在温升影响方面,与等量温排水单独排放相比,混合排放会使底层海域温升包络面积增大,表层减小,但当混合比例超过1:30(温排水量约为35 m³/s),表层和底层海域温升包络面积接近于等量温排水单独排放的温升包络面积;综合考虑温盐扩散,当海水淡化浓海水排放量在10×104 m³/d,盐升不超过20时,与温排水混合排放比例超过1:30(温排水量超过35 m³/s),盐度在排放口附近可稀释到背景值,由于混合排放密度变化引起的温度下沉影响几乎可以忽略不计。相关研究结论可为海水淡化浓海水科学排放/推动海水淡化和海洋环境和谐可持续发展提供技术支撑。  相似文献   

5.
利用海洋调查船“实践”号在首次全球大气试验(PGGE)期间所取得的典型的海面气象及深度温度计观测资料,较详细地分析了西太平洋赤道海区对流性降水对海洋表层温、盐结构的影响。计算了受降水影响的海水薄层中的热量收支,所得结果与观测事实基本相符。  相似文献   

6.
对台湾海峡南部海区1997年8月的CTD资料进行子温、盐垂直结构分析。结果表明:大部分调查海域存在温、盐跃层;台湾浅滩南部和东南部海域的温、盐垂直结构较为复杂,这与多种水系在此交汇有关,但下层海水的低温高盐特性仍表明这一海域是上升流区;泉州外海的下层存在低温高盐海水的爬升,但没有影响到表层。  相似文献   

7.
电磁感应式电导率传感器(Type Inductive Conductivity Sensor,TICS)自身探测结构的不外露,可以避免磁芯线圈的腐蚀,提高海水电导率探测的稳定性。但是感应式电导率传感器磁芯的相对磁导率不仅受到外界温度和压力的影响,其随工作频率的增加也会有很大的衰减,导致输出信号过小,分辨率降低。本文首先对感应式探头的物理结构参数、输入信号参数进行理论分析,根据理论分析的结构参数,定制了感应式探头,最后经过实验论证,得出了探头结构参数、工作信号参数的选择依据,可以更好地提高输出信号的准确度与分辨率。  相似文献   

8.
地磁感应线圈在投弃式探头水下转速测量中的应用   总被引:1,自引:0,他引:1  
介绍了地磁感应线圈的工作原理,针对投弃式探头水下转速测量需要,设计专用线圈传感器及测量电路,并搭建专用试验台进行室内试验。试验结果表明,采用地磁感应线圈可以准确地得到旋转体转速信息,可应用于投弃式探头水下转速测量。  相似文献   

9.
海洋磁力仪拖鱼入水深度试验证明:当拖缆长度达到一定距离以后,拖鱼入水深度不再发生明显变化。在试验的基础上,分析海洋磁力仪拖鱼水中受力情况,综合考虑海水阻力、拖缆长度、航行速度和配重等因素,提出拖鱼入水深度的计算方法。  相似文献   

10.
渤、黄、东海内潮的数值模拟   总被引:2,自引:0,他引:2  
在全球的海洋中,中国东海和临近海域是最显著的内潮生成地之一。本文采用NODC(Levitus) World Ocean Atlas 1998提供的季平均温、盐资料,计算海水的密度,并计算垂向密度梯度的最大值点,得到一个较符合海水实际的密度分层。使用三维非线性数值模型(将海洋分为2层)研究了潮汐(M2,S2,K1,O1分潮)作用下渤黄东海的内潮,揭示了整个海区内潮起伏的空间分布,结果发现大振幅的波动均发生在台湾东北(冲绳海槽)海域和中国近海地形突变之处,其中前者更显著。对于各分潮模拟得到的表面潮与TOPEX/Poseidon高度计资料基本一致。研究结果表明上层海水的深度和厚度的梯度对内潮有一定的影响;冬季分布区域比夏季小,强度比夏季大。  相似文献   

11.
A “slip law” connects the excess velocity or “slip” of a wind-blown water surface, relative to the motion in the middle of the mixed layer, to the wind stress, the wind-wave field, and buoyancy flux. An inner layer-outer layer model of the turbulent shear flow in the mixed layer is appropriate, as for a turbulent boundary layer or Ekman layer over a solid surface, allowing, however, for turbulent kinetic energy transfer from the air-side via breaking waves, and for Stokes drift. Asymptotic matching of the velocity distributions in inner and outer portions of the mixed layer yields a slip law of logarithmic form, akin to the drag law of a turbulent boundary layer. The dominant independent variable is the ratio of water-side roughness length to mixed layer depth or turbulent Ekman depth. Convection due to surface cooling is also an important influence, reducing surface slip. Water-side roughness length is a wind-wave property, varying with wind speed similarly to air-side roughness. Slip velocity is typically 20 times water-side friction velocity or 3% of wind speed, varying within a range of about 2 to 4.5%. A linearized model of turbulent kinetic energy distribution shows much higher values near the surface than in a wall layer. Nondimensional dissipation peaks at a value of about eight, a short distance below the surface.  相似文献   

12.
通过对MDT测压资料的分析,发现了造成测试点压力值存在误差的主要原因有两个方面:一方面是由于部分测压点储层物性差,测试探针抽吸地层流体后储层压力恢复需要的时间较长,然而由于实际原因测试压力恢复无法等待足够的测试时间;另一方面是由于部分物性较差储层较难形成好的泥饼,以至于受到比较严重的泥浆侵入使得测试点产生超压现象,测试得到的地层压力和实际压力相比偏大.同时分析发现物性较好的储层往往能够得到相对可靠的测试压力.合理的气水界面对于计算探明地质储量有着很重要的意义,尤其是高温高压气田,气水过渡带往往较大,可能会达到30m左右,这种情况下无法仅从钻遇情况分析气水界面,此时可以结合MDT测压资料分析气水界面,从而确定合理的地质储量.通过分析实际MDT测压资料,对不同测压点进行了误差分析并在此基础上提出了压力数据点的筛选原则.通过实际检验认为新的回归方法确定出的气水界面科学合理.  相似文献   

13.
A diagnostic study is performed in the paper on the process of typhoon Norris (1980) transforming into an ex-tratropical cyclone after its landing over Southeast China. The main findings are as follows:The changes of kinetic energy are mainly attributed to the generation due to non-divergent wind. During the early stage of the typhoon landing, there exits only a small quantity of kinetic energy exchanging with the environment. And after it is transformed into an extratropical cyclone, a large amount of kinetic energy is exported from the system toward the environment.The horizontal and vertical flux-divergence terms of eddy available potenlial energy are the prominent sinks in the budgets of eddy kinetic energy. The generations of eddy kinetic energy due to both the barotropic and baroclinic processes are source terms. The former is remarkable during the initial stage. But after the depression is transformed into an extratropical cyclone, the roles of the generation by the barotropic and baroclinic proc  相似文献   

14.
基于Galieo变换,导出了运动坐标系与静止坐标系中海浪谱间的关系。由于海浪是频散的,两者间的关系是频率相关的。运动坐标系中的海浪频谱是与静止坐标系中的海浪方向谱相联系的。以文氏谱作为静止坐标系中的海浪频谱,给出了不同速度下运动坐标系中的海浪频谱。  相似文献   

15.
Monthly mesoscale eddy kinetic energy (EKE) per unit mass has been computed for four years, 1993-1996, from TOPEX altimeter data in the Indian Ocean. It ranges from 50 cm2/s2 to 2,700 cm2/s2 (about 4,000 cm2/s2 near the Somali region in a few months). In the Arabian Sea and the Bay of Bengal, regions of high energies associated with various current systems under the influence of monsoonal winds have been delineated. Monthly variation of EKE near the Somali region has been studied. In this region the maximum EKE per unit mass has been observed during August every year, with variations in magnitude from year to year. The mesoscale eddy kinetic energy computed from TOPEX altimeter-derived SSH during 1993-1996 is highest near the Somali region during the SW monsoon, due to formation of mesoscale eddies and also because of upwelling. In the Bay of Bengal, high eddy kinetic energy is seen toward the western side during nonmonsoonal months due to the western boundary current. In the South Indian Ocean, it is high at a few places in some of the months. A large part of the Indian Ocean exhibits low eddy kinetic energy (less than 300 cm2/s2) year-round.  相似文献   

16.
利用2019年7月在长江口科学考察实验研究夏季航段(NORC2019-03-02)中获得的MSS90L湍流剖面仪的直接观测数据,本文计算并分析了该断面的湍动能耗散率ε和垂向湍扩散系数KZ的分布情况。湍动能耗散率的大小为1.72×10?10~2.95×10?5 W/kg;垂向湍扩散系数的大小为3.24×10?7~4.55×10?2 m2/s。湍动能耗散率和垂向湍扩散系数的分布相似,均为上层最强,底层次之,中层最弱。上层由于风应力的作用,使得湍动能耗散率和垂向湍扩散系数较大;温跃层处层化较强,抑制了湍动能的耗散和垂向上的湍混合。盐度锋面的次级环流会促使低盐水团脱离,锋面引起的垂向环流会加强海洋的湍混合。低盐水团与外界的能量交换较少,湍动能耗散率较弱。长江口海区存在明显的上升流和下降流,它们是由锋面的次级环流产生的;上升流和下降流的存在促进湍动能的耗散与湍混合。  相似文献   

17.
《Ocean Modelling》2002,4(3-4):347-361
An energy-conserving discretisation of the shear and buoyancy production terms for turbulent kinetic energy is derived. In contrast to `ad hoc' numerical schemes, this guarantees that all mean kinetic and potential energy which is lost or gained due to vertical mixing is exactly subtracted or added to the turbulent kinetic energy budget. It is further shown in a numerical wind-entrainment experiment that this new methods results in significantly more stable numerical solutions.  相似文献   

18.
Monthly mesoscale eddy kinetic energy (EKE) per unit mass has been computed for four years, 1993-1996, from TOPEX altimeter data in the Indian Ocean. It ranges from 50 cm2/s2 to 2,700 cm2/s2 (about 4,000 cm2/s2 near the Somali region in a few months). In the Arabian Sea and the Bay of Bengal, regions of high energies associated with various current systems under the influence of monsoonal winds have been delineated. Monthly variation of EKE near the Somali region has been studied. In this region the maximum EKE per unit mass has been observed during August every year, with variations in magnitude from year to year. The mesoscale eddy kinetic energy computed from TOPEX altimeter-derived SSH during 1993-1996 is highest near the Somali region during the SW monsoon, due to formation of mesoscale eddies and also because of upwelling. In the Bay of Bengal, high eddy kinetic energy is seen toward the western side during nonmonsoonal months due to the western boundary current. In the South Indian Ocean, it is high at a few places in some of the months. A large part of the Indian Ocean exhibits low eddy kinetic energy (less than 300 cm2/s2) year-round.  相似文献   

19.
Laboratory equipment has been built which will measure the permeability and thermal conductivity of deep-sea sediments at their in-situ conditions of hydrostatic pressure, temperature, and void ratio. The apparatus has the capability of uniaxially consolidating a sediment sample to simulate compaction within the sediment column, while exposing the specimen to hydrostatic pressures ranging from atmospheric to 62 MPa and to temperatures from 22 to 220°C. The equipment includes a hypodermic needle mounted vertically through the base of the pressure vessel from which thermal conductivity is determined by the needle probe method. The system also features a combination of dead-weight testers which produces a small hydraulic gradient across the sample and permits the measurement of sediment permeability at large hydrostatic pressures.The physical property data generated from this apparatus will be important in understanding the mechanisms of heat transfer through the ocean floor and in analysing the coupled flow of heat and pore fluid in the vicinity of a heat source, such as a radioactive waste canister, buried in the seabed.  相似文献   

20.
陈松  廖文卓 《台湾海峡》1996,15(1):36-40
本文模拟研究了污水颗粒物-海水体系中磷的转移过程。污水颗粒物与海水混合之后先是快速吸附磷,之后即以约0.3d^-1的速率进行释放。总过程仍表现为磷的释放。磷的吸附-释放属于离子交换性质,可用交换平衡动力学模式表示。溶解磷含量的增加速率符合一级动力学方程。  相似文献   

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