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Experimental and Numerical Investigation of Green Water Occurrence for KRISO Container Ship KRISO集装箱船绿水发生的实验与数值研究
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-23 DOI: 10.5957/JOSR.08200049
K. R. Babu, Sri Vinay Krishna Rayudu Nelli, A. Bhattacharyya, R. Datta
The occurrence of green water on the deck of Korea Research Institute of Ships & Ocean Engineering (KRISO) container ship is investigated using model test experiments and a fully coupled impulse response function (IRF)-computational fluid dynamics (CFD)-based numerical approach. In the experimental study, green water pressure over the deck and superstructure is investigated for different regular head wave conditions (wavelength/ship length ratio: .8-1.5) and vessel speeds (Froude number: .055-.166). The impact pressure on the deck is found to be highest at a wavelength/ship length ratio of 1.2 and increases drastically with the increase in Froude number. The variation of green water pressure with wave steepness is linear for points on the forward deck and quadratic for the superstructure. In the second part, a coupled IRF-CFD-based numerical method is developed in which the global hydrodynamic forces such as radiation-diffraction and Froude-Krylov force are computed using a potential flow solver, whereas the local pressure due to the shipping water impact is computed using CFD and added as an external force. Comparisons of vessel motions and green water pressures with experiments indicate that the coupled IRF-CFD method can be a robust and efficient tool to predict shipping water loads on ships.
通过模型试验和基于全耦合脉冲响应函数(IRF)计算流体动力学(CFD)的数值方法,研究了韩国船舶与海洋工程研究所(KRISO)集装箱船甲板上绿水的发生。在实验研究中,研究了不同规则头波条件(波长/船长比:.8-1.5)和船舶速度(弗劳德数:.055-.166)下甲板和上部结构上的生水压力。发现在波长/船长比为1.2时,甲板上的冲击压力最高,并随着弗劳德值的增加而急剧增加。对于前甲板上的点来说,生水压力随波浪陡度的变化是线性的,对于上部结构来说是二次的。在第二部分中,开发了一种基于IRF CFD的耦合数值方法,其中使用势流求解器计算全局流体动力,如辐射衍射和Froud-Krylov力,而使用CFD计算航运水冲击引起的局部压力,并将其作为外力添加。船舶运动和生水压力与实验的比较表明,IRF-CFD耦合方法是预测船舶航运水荷载的一种稳健有效的工具。
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引用次数: 4
Assessing the Interplay of Shape and Physical Parameters by Unsupervised Nonlinear Dimensionality Reduction Methods 用无监督非线性降维方法评估形状和物理参数的相互作用
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-21 DOI: 10.5957/josr.09180056
A. Serani, D. D’Agostino, E. Campana, M. Diez
The article presents an exploratory study on the application to ship hydrodynamics of unsupervised nonlinear design-space dimensionality reduction methods, assessing the interaction of shape and physical parameters. Nonlinear extensions of the principal component analysis (PCA) are applied, namely local PCA (LPCA) and kernel PCA (KPCA). An artificial neural network approach, specifically a deep autoencoder (DAE) method, is also applied and compared with PCA-based approaches. The data set under investigation is formed by the results of 9000 potential flow simulations coming from an extensive exploration of a 27-dimensional design space, associated with a shape optimization problem of the DTMB 5415 model in calm water at 18 kn (Froude number, Fr = 25). Data include three heterogeneous distributed and suitably discretized parameters (shape modification vector, pressure distribution on the hull, and wave elevation pattern) and one lumped parameter (wave resistance coefficient), for a total of 9000 x 5101 elements. The reduced-dimensionality representation of shape and physical parameters is set to provide a normalized mean squared error smaller than 5%. The standard PCA meets the requirement using 19 principal components/parameters. LPCA and KPCA provide the most promising compression capability with 14 parameters required by the reduced-dimensionality parametrizations, indicating significant nonlinear interactions in the data structure of shape and physical parameters. The DAE achieves the same error with 17 components. Although the focus of the current work is on design-space dimensionality reduction, the formulation goes beyond shape optimization and can be applied to large sets of heterogeneous physical data from simulations, experiments, and real operation measurements.
本文对无监督非线性设计空间降维方法在船舶水动力学中的应用进行了探索性研究,评估了形状和物理参数的相互作用。应用了主成分分析的非线性扩展,即局部主成分分析(LPCA)和核主成分分析(KPCA)。本文还应用了人工神经网络方法,特别是深度自编码器(DAE)方法,并与基于pca的方法进行了比较。所研究的数据集是由9000个势流模拟的结果组成的,这些模拟来自于对27维设计空间的广泛探索,并与DTMB 5415模型在平静水中18 kn (Froude数,Fr = 25)的形状优化问题相关。数据包括三个非均匀分布和适当离散化的参数(形状修正矢量、船体上的压力分布和波浪高程模式)和一个集总参数(波浪阻力系数),总共9000 x 5101个元素。形状和物理参数的降维表示设置为提供小于5%的归一化均方误差。标准PCA使用19个主成分/参数满足要求。LPCA和KPCA提供了最有希望的压缩能力,具有降维参数化所需的14个参数,表明形状和物理参数的数据结构存在显著的非线性相互作用。DAE对17个组件实现相同的误差。虽然目前的工作重点是设计空间降维,但该公式超越了形状优化,可以应用于来自模拟、实验和实际操作测量的大型异构物理数据集。
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引用次数: 8
Effect of Ship-Induced Langmuir-Type Circulations on Distribution of Surface-Active Substances and Damping of Short Wind Waves 船舶诱导的langmuir型环流对海面活性物质分布和短风浪阻尼的影响
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-21 DOI: 10.5957/josr.10180090
Ryan Somero, A. Basovich, E. Paterson
It has recently been shown that the interaction of ship-generated nonuniform currents with ambient surface waves can lead to the generation of Langmuir-type circulations (LTCs) (Basovich 2011) and a persistent wake (Somero et al. 2018). Based on this work, it is shown here that the LTC and surface currents of the persistent wake are responsible for the redistribution of surface-active substances (SAS) and a corresponding change in the damping of short surface waves. The persistent wake is a region of the ship wake, where initial ship-generated perturbations have mostly decayed. The LTCs are similar in nature to Langmuir circulations which arise as a result of instability of wind-driven current. LTCs produce a secondary flow with velocity transverse to the direction of the ship, and width significantly larger than the ship beam. Because LTCs are generated in large scale, they persist for a long time after the passage of the ship. Transverse surface currents produced by LTCs in the ship wake redistribute the SAS films at the sea surface. These currents create strong convergence and divergence zones which in turn produce streaks with different concentrations of SAS. The change in concentration of SAS affects the film pressure and the damping effect of SAS on the short surface waves. This effect is represented by a damping factor and is a crucial parameter in determination of the spectral density of short wind waves. Therefore, the damping effect of the film, as represented by the damping factor, is responsible for sea surface roughness modification and is important for prediction of synthetic-aperture RADAR (SAR) imagery of ship wakes on the ocean surface. In this article, we present the mathematical and computational methods, along with simulation results for a naval surface combatant operating in calm, head, and following seas. The simulation results clearly show that the convergence and divergence zones strongly influence the relative SAS concentration and the spatial distribution of the damping factor, the latter of which defines the structure of SAR images of the persistent wake. Comparisons of the magnitude of the damping factor with available SAR data are shown to be in good agreement.
最近有研究表明,船舶产生的非均匀流与环境表面波的相互作用可导致langmuir型环流(LTCs)的产生(Basovich 2011)和持续尾流(Somero et al. 2018)。基于这项工作,本文表明,持久尾流的LTC和表面流负责表面活性物质(SAS)的再分配和相应的短表面波阻尼的变化。持续尾流是船舶尾流的一个区域,在这个区域中,初始的船舶产生的扰动大部分已经减弱。长期环流在性质上类似于由风力驱动的洋流不稳定引起的朗缪尔环流。LTCs产生的二次流,其速度与船舶方向横向,宽度明显大于船舶光束。由于LTCs是大规模产生的,因此在船舶通过后会持续很长时间。船舶尾流中LTCs产生的横向表面流重新分配了海面上的SAS膜。这些气流形成强烈的辐合区和辐散区,进而产生具有不同浓度SAS的条纹。SAS浓度的变化影响了膜压力和SAS对短表面波的阻尼作用。这种效应用阻尼系数表示,是确定短风波谱密度的关键参数。因此,薄膜的阻尼效应(以阻尼因子为代表)负责海面粗糙度的改变,对海面船舶尾迹合成孔径雷达(SAR)成像的预测具有重要意义。在这篇文章中,我们提出了数学和计算方法,以及海军水面作战人员在平静、头部和后续海域作战的模拟结果。模拟结果清楚地表明,辐合区和辐散区对持续尾流的相对SAS浓度和阻尼因子的空间分布有较大影响,阻尼因子的空间分布决定了持续尾流SAR图像的结构。阻尼系数的大小与现有SAR数据的比较显示出很好的一致性。
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引用次数: 0
Experimental Analysis of Repair Welding Alternatives for Shipbuilding DH36 Plates 船舶DH36钢板补焊方案试验分析
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-21 DOI: 10.5957/JOSR.07180035
T. Gurova, S. Estefen, A. Leontiev, Plínio T. Barbosa, V. Zhukov, Vasilii Nikulin
Repair by welding is widely used in the shipbuilding industry during ship construction. The effect of the residual stress distribution induced by the welding process on the ship structure is important for the repair effectiveness. This article presents an experimental study of the residual stress distribution induced by repair welding in the plates that are typically used in ships and offshore structures. Different repair techniques are evaluated to identify the best practice associated with residual stress values. Recommendations for repair welding are discussed, and modifications to the present practice are proposed.
在船舶建造过程中,焊接修复在造船业中被广泛使用。焊接过程中产生的残余应力分布对船舶结构的修复效果有重要影响。本文对船舶和海上结构物中常用的板件补焊引起的残余应力分布进行了实验研究。评估不同的修复技术,以确定与残余应力值相关的最佳实践。对补焊的建议进行了讨论,并对目前的做法提出了修改意见。
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引用次数: 1
Captive Model Tests for Assessing Maneuverability of a Damaged Surface Combatant with Initial Heel Angle 具有初始跟角的受损水面战斗舰艇机动性能评估的俘虏模型试验
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-21 DOI: 10.5957/JOSR.09180075
Jeonghwa Seo, D. Kim, J. Ha, S. Rhee, H. Yoon, Jongyeol Park, W. Seok, K. Rhee
The present study is about the application of a four-degree-of-freedom (4DOF) maneuvering mathematical model based on Abkowitz’s model for assessing damaged ship maneuverability with initial asymmetry. A scaled model of the Office of Naval Research Tumblehome hull with a damaged compartment was used as the test model. Based on the survivability regulations for naval vessels, the damaged compartment was designed and located near the bow, such that it had an initial heel and trim. Static and dynamic captive model tests were performed on the damaged ship model to determine the maneuvering coefficients for the maneuvering mathematical model. Maneuvering simulations were carried out with the captive model test data and 4DOF maneuvering mathematical model. The advance speed in the maneuver reduced more in the damaged condition than in the intact condition, and maneuverability was severely degraded during starboard turning.
本研究是关于应用基于Abkowitz模型的四自由度(4DOF)操纵数学模型来评估具有初始不对称性的受损船舶操纵性。使用海军研究办公室翻滚房屋船体的缩放模型作为测试模型,该模型带有损坏的舱室。根据海军舰艇的生存能力规定,受损舱室的设计和位置靠近船头,因此它有一个初始的跟部和纵倾。对受损船舶模型进行了静态和动态捕获模型试验,以确定机动数学模型的机动系数。利用捕获模型试验数据和4DOF机动数学模型进行了机动仿真。机动中的推进速度在受损状态下比在完好状态下降低得更多,右舷转弯时机动性能严重下降。
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引用次数: 5
Study of a Container Ship with Breaking Waves at High Froude Number Using URANS and DDES Methods 用URNS和DDES方法研究集装箱船在高弗劳德数下的破碎波
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-21 DOI: 10.5957/josr.09180081
Jianhua Wang, Z. Ren, D. Wan
The KRISO container ship model is used for numerical simulations to investigate hydrodynamic performance under high speeds. Unsteady Reynolds-Averaged Navier-Stokes (URANS) and delayed detached eddy simulation (DDES) approaches are used to resolve the flow field around the ship model. High-resolution Volume of Fluid (VOF) technique in OpenFOAM is used to capture the free surface. The present work focuses on the wave-breaking phenomena of high-speed ships. To study the speed effects on the phenomenon of ship bow wave breaking, three different speeds, i.e., Fn = .26, .35, and .40, are investigated for a fixed ship model in calm water. Predicted resistance and wave patterns under Fn = .26 are validated with available experimental data, and a good agreement is achieved. The breaking wave phenomena can be observed from both URANS and DDES results for Froude numbers greater than .35. And the Fn = .40 case shows more violent breaking bow waves. The process of overturning and breaking of bow wave is more complex in the DDES results, and some small-scale free surface features are also captured. The predicted bow wave is compared with the experiment conducted at the China Ship Scientific Research Center. It shows that the DDES results are more accurate. Wave profiles and vorticity field at several cross sections are presented to illustrate the relationship between bow waves and vortices. It is found that the free surface vorticity dissipates quickly in the URANS simulation, which leads to the difference compared with the DDES results.
采用KRISO集装箱船模型对高速下的船舶水动力性能进行了数值模拟。采用非定常reynolds - average Navier-Stokes (URANS)方法和延迟分离涡模拟(DDES)方法来求解船舶模型周围的流场。OpenFOAM中的高分辨率流体体积(VOF)技术用于捕获自由表面。本文主要研究高速船舶的破波现象。为了研究航速对船首破波现象的影响,在静水中对固定船模进行了三种不同航速Fn = .26、.35和.40的研究。用已有的实验数据验证了Fn = .26下的预测电阻和波形,结果吻合较好。当弗劳德数大于0.35时,URANS和DDES结果均可观察到破碎波现象。Fn = .40的情况显示出更猛烈的弓形波。在DDES结果中,弓形波的翻转和破碎过程更为复杂,并且还捕获了一些小尺度的自由表面特征。并与中国船舶科学研究中心的试验结果进行了比较。结果表明,DDES计算结果更加准确。为了说明弓形波与涡的关系,文中给出了几个截面上的波浪剖面和涡度场。发现在URANS模拟中,自由表面涡度耗散较快,这与DDES模拟结果存在差异。
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引用次数: 14
Modeling Bubble Entrainment and Transport for Ship Wakes: Progress Using Hybrid RANS/LES Methods 船舶尾迹的气泡夹带和运输建模:使用混合RANS/LES方法的进展
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-21 DOI: 10.5957/josr.09180071
Jiajia Li, Ben Yuan, P. Carrica
This article presents progress on modeling bubble entrainment and transport around ships using hybrid Reynolds-averaged Navier-Stokes/large eddy simulation (RANS/ LES) methods. Previous results using a Boltzmann-based polydisperse bubbly flow model show that LES perform better than RANS in predicting transport of bubbles to depth, a very important process to predict bubbly wakes. However, standard DES-type models fail to predict proper turbulent kinetic energy (TKE) and dissipation, needed by bubble entrainment, breakup, and coalescence models. We propose different approaches to obtain TKE and dissipation in LES regions and evaluate them for cases of increasing complexity, including decay of isotropic turbulence, a flat plate boundary layer, and the flow in the wake of the research vessel Athena. An exponential weighted average is used to estimate statistics and obtain the averaged quantities in regions with resolved turbulence. The TKE is satisfactorily predicted in the cases tested. A modified ω equation in the SST model is proposed to implicitly compute the dissipation, showing superior results than the standard DES models, although further improvements are necessary. A hybrid RANS/LES approach is proposed, which focused at conserving total TKE as the flow crosses RANS/LES interfaces, as previously performed for zonal approaches but attempting a DES-like detection of regions suitable for LES, critical for large-scale computations of bubbly flows involving complex geometries. A general form of a dynamic forcing term is derived to transfer the modeled TKE to resolved TKE with a controller to guarantee proper conservation of the energy transferred. It was verified that the model is not sensitive to grid size or time step. Improvements to DDES and the proposed TKE-conserving hybrid RANS/ LES method show encouraging results, although remaining challenges are discussed.
本文介绍了使用雷诺平均Navier-Stokes/大涡模拟(RANS/LES)混合方法模拟船舶周围气泡夹带和传输的进展。先前使用基于玻尔兹曼的多分散气泡流模型的结果表明,LES在预测气泡向深度的传输方面比RANS表现得更好,这是预测气泡尾流的一个非常重要的过程。然而,标准DES型模型无法预测气泡夹带、破碎和聚结模型所需的适当湍流动能(TKE)和耗散。我们提出了在LES区域获得TKE和耗散的不同方法,并在复杂性增加的情况下对其进行评估,包括各向同性湍流的衰减、平板边界层和研究船Athena尾流。指数加权平均用于估计统计数据,并获得具有解析湍流的区域中的平均量。TKE在测试的病例中得到了令人满意的预测。在SST模型中提出了一个修正的ω方程来隐式计算耗散,显示出比标准DES模型更好的结果,尽管还需要进一步的改进。提出了一种混合的RANS/LES方法,该方法的重点是在流动穿过RANS/LES界面时保持总TKE,正如之前对区域方法所做的那样,但尝试对适用于LES的区域进行类似DES的检测,这对于涉及复杂几何形状的泡状流的大规模计算至关重要。导出了动态强迫项的一般形式,以通过控制器将建模的TKE转换为解析的TKE,从而确保所转换的能量的适当守恒。经验证,该模型对网格大小或时间步长不敏感。对DDES和所提出的TKE守恒混合RANS/LES方法的改进显示出令人鼓舞的结果,尽管还讨论了剩余的挑战。
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引用次数: 8
Ultimate Strength of Hull Structural Stiffened Plate with Grooving Corrosion Damage under Uniaxial Compression 槽腐蚀损伤船体结构加筋板在单轴压缩下的极限强度
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-11 DOI: 10.5957/JOSR.03200014
Yufan Zhu, Yan Zhang, F. Du
Grooving corrosion results in a decrease in the ability of the structure to resist external loads. In the present study, a new assessment method was developed to investigate the ultimate loading capacity of stiffened plates with grooving corrosion damage. First, the basic parameters of stiffened plates (including model range, boundary condition, welding residual stress, initial geometric imperfection, and size of finite element) were assumed. Second, the influences of corrosion parameters and geometrical parameters of stiffened plates (such as finite element type, groove width, groove depth, groove depth-to-width ratio, plate flexibility, stiffener flexibility, and number of stiffeners) were analyzed. Third, based on the data analysis from a large number of nonlinear finite element analyses, the ultimate strength reduction formula of stiffened plates was derived. Last, the correctness of the formula was verified by ultimate strength experiment.
沟槽腐蚀导致结构抵抗外部载荷的能力下降。在本研究中,开发了一种新的评估方法来研究具有槽腐蚀损伤的加筋板的极限承载能力。首先,假设了加筋板的基本参数(包括模型范围、边界条件、焊接残余应力、初始几何缺陷和有限元尺寸)。其次,分析了腐蚀参数和加筋板几何参数(如有限元类型、槽宽、槽深、槽深宽比、板柔性、加劲肋柔性和加劲肋数量)的影响。第三,在大量非线性有限元分析数据的基础上,推导了加筋板的极限强度折减公式。最后通过极限强度试验验证了公式的正确性。
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引用次数: 0
Enhanced Unified Theory with Forward-Speed Effect Taken into Account in the Inner Free-Surface Condition 内自由面条件下考虑前进速度效应的增强统一理论
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-01 DOI: 10.5957/JOSR.04200028
M. Kashiwagi
The enhanced unified theory (EUT) has been used as a core theory in the integrated system developed at the Research Initiative on Oceangoing Ships (RIOS) of Osaka University for predicting the propulsion and seakeeping performance of a ship in actual seas. In this study, the EUT is modified by adopting partially the solution method in the rational strip theory of Ogilvie and Tuck as a particular solution in the inner problem, thereby a forward-speed effect in the convection term of the free-surface condition is incorporated in the inner solution. This forward-speed effect is analytically shown to contribute only to the cross-coupling radiation forces. Some other forward-speed and 3D effects important in a low-frequency range are also included in the homogeneous component of the inner solution through matching with the outer solution in a similar manner to the unified theory of Newman. Numerical computations are implemented for a slender modified Wigley model and the RIOS bulk carrier model. Good agreement is confirmed in a comparison with experimental data for the cross-coupling added mass and damping coefficients between heave and pitch and also for the resulting ship motions, particularly in heave near the resonant frequency. The added resistance around the motion-resonant wavelength is found to be improved but sensitive to a slight change in heave and pitch motions. Thus, it is stressed that accurate prediction of the ship motions and resultant Kochin function is critical for more accurate prediction of the added resistance in waves.
增强统一理论(EUT)已被用作大阪大学远洋船舶研究计划(RIOS)开发的集成系统的核心理论,用于预测船舶在实际海洋中的推进和耐波性能。在本研究中,通过部分采用Ogilvie和Tuck的有理条理论中的求解方法作为内部问题的特定解,对EUT进行了修改,从而在内部解中加入了自由表面条件对流项中的正向速度效应。分析表明,这种正向速度效应只对交叉耦合辐射力有贡献。以类似于Newman统一理论的方式,通过与外部解的匹配,在低频范围内重要的其他一些正向速度和3D效应也被包括在内部解的均匀分量中。对细长修正Wigley模型和RIOS散货船模型进行了数值计算。通过与实验数据的比较,证实了良好的一致性,这些数据涉及升沉和纵摇之间的交叉耦合附加质量和阻尼系数,以及由此产生的船舶运动,特别是在共振频率附近的升沉中。发现运动谐振波长周围增加的阻力得到了改善,但对起伏和俯仰运动的微小变化敏感。因此,需要强调的是,准确预测船舶运动和由此产生的Kochin函数对于更准确地预测波浪中的附加阻力至关重要。
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引用次数: 3
Turbulent Skin Friction Reduction through the Application of Superhydrophobic Coatings to a Towed Submerged SUBOFF Body 超疏水涂层在水下拖曳体上的应用减少湍流表面摩擦
IF 1.4 4区 工程技术 Q3 ENGINEERING, CIVIL Pub Date : 2020-12-01 DOI: 10.5957/JOSR.10190060
J. Gose, Kevin Golovin, Mathew Boban, Brian Tobelmann, E. Callison, J. Barros, M. Schultz, A. Tuteja, M. Perlin, S. Ceccio
In the present study, the drag-reducing effect of sprayed superhydrophobic surfaces (SHSs) is determined for two external turbulent boundary layer (TBL) flows. We infer the modification of skin friction created beneath TBLs using near-wall laser Doppler velocity measurements for a series of tailored SHSs. Measurements of the near-wall Reynolds stresses were used to infer reduction in skin friction between 8% and 36% in the channel flow. The best candidate SHS was then selected for application on a towed submersible body with a SUBOFF profile. The SHS was applied to roughly 60% of the model surface over the parallel midbody of the model. The measurements of the towed resistance showed an average decrease in the overall resistance from 2% to 12% depending on the speed and depth of the towed model, which suggests a SHS friction drag reduction of 4-24% with the application of the SHS on the model. The towed model results are consistent with the expected drag reduction inferred from the measurements of a near-zero pressure gradient TBL channel flow.
在本研究中,确定了喷涂超疏水表面(SHSs)对两种外部湍流边界层(TBL)流动的减阻效果。我们使用近壁激光多普勒速度测量来推断TBLs下产生的表面摩擦的变化。通过测量近壁面的雷诺应力,可以推断出通道流动中表面摩擦减少了8%至36%。然后选择最佳候选SHS应用于具有SUBOFF剖面的拖曳潜水体。SHS应用于模型平行中体上方约60%的模型表面。拖曳阻力的测量结果显示,根据拖曳模型的速度和深度,整体阻力平均下降2%至12%,这表明在模型上应用SHS后,SHS摩擦阻力减少了4-24%。拖曳模型的结果与从接近零压力梯度的TBL通道流的测量中推断出的预期阻力减少一致。
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引用次数: 4
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Journal of Ship Research
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