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Concept of Vibroacoustic Diagnostics of the Fuel Injection and Electronic Cylinder Lubrication Systems of Marine Diesel Engines 船用柴油机燃油喷射和电子缸润滑系统的振动声诊断概念
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-12-01 DOI: 10.2478/pomr-2022-0046
R. Varbanets, Oleksandr Shumylo, A. Marchenko, D. Minchev, V. Kyrnats, V. Zalozh, N. Aleksandrovska, Roman Brusnyk, Kateryna Volovyk
Abstract Although direct measurements of the fuel injection pressure and the travel of the injector needle in conjunction with measurements of the valve train mechanism timing can provide complete diagnostic information about the technical conditions of the fuel injection and valve train systems, this requires the installation of sensors and other equipment directly into the systems, which is possible within research laboratories but is generally forbidden during operation of the ship. Malfunctions in the fuel injection and valve train systems can also be identified from the indicator diagrams of an engine operating cycle, expressed as P(V) and P(deg) diagrams. The basic parameters of the engine operating cycle, such as the maximum combustion pressure Pmax, compression pressure Pcompr, and indicated mean effective pressure IMEP, can also be used to indicate deviations from proper engine operation. Using a combination of a vibration sensor with an in-cylinder gas pressure sensor widens the capabilities of diagnostics for marine diesel engines under operational conditions. A vibration sensor with a magnetic base can help in determining the timings of the lifting and landing of the injector needle, fuel delivery by the fuel injection pump, opening and closing of the circulation of heated heavy fuel oil, and opening and closing of the gas distribution valves. This also offers a promising solution for diagnostics of the cylinder lubrication oil injectors. The proposed approach allows valuable information to be received during engine operation in accordance with the principle of non-destructive control, and can help in early detection of possible engine malfunctions.
虽然直接测量燃油喷射压力和喷油器针的行程以及配气机构正时的测量可以提供有关燃油喷射和配气机构技术状况的完整诊断信息,但这需要在系统中直接安装传感器和其他设备,这在研究实验室中是可能的,但在船舶操作中通常是禁止的。燃油喷射和气门传动系统的故障也可以从发动机工作循环的指示图中识别出来,表示为P(V)图和P(度)图。发动机工作循环的基本参数,如最大燃烧压力Pmax,压缩压力Pcompr,指示平均有效压力IMEP,也可以用来指示偏离发动机正常工作。将振动传感器与缸内气体压力传感器结合使用,可扩大船用柴油机在运行条件下的诊断能力。带有磁性底座的振动传感器可以帮助确定喷油器针的升降和降落时间、喷油泵的燃油输送时间、加热重质燃料油循环的开启和关闭时间,以及气体分配阀的开启和关闭时间。这也为气缸润滑油喷射器的诊断提供了一个有前途的解决方案。根据非破坏性控制的原则,该方法可以在发动机运行过程中接收有价值的信息,并有助于早期发现可能的发动机故障。
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引用次数: 4
Review of the Container Ship Loading Model – Cause Analysis of Cargo Damage and/or Loss 集装箱船装载模型回顾-货物毁损和/或灭失原因分析
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-12-01 DOI: 10.2478/pomr-2022-0041
M. Kaup, D. Łozowicka, Karolina Baszak, W. Ślączka, A. Kalbarczyk-Jedynak
Abstract As the maritime transport of containers continues to grow and container ships change in terms of design and construction, it is important to ensure the appropriate level of safety for this type of transport. Over the decades, the size and cargo capacity of container ships have been changing, and so have their manoeuvring restrictions and required stability criteria. It seems that changes in the regulations, technological development and increased stability requirements are not yielding satisfactory results – the causes of container ship accidents continue to show similar patterns. The present article refers to the problem of ensuring safety in sea container transport, with a particular focus on cargo processes. Its purpose is to determine cause-and-effect relations leading to the loss of containers at sea, and to develop a model of loading that could significantly raise the level of safety of container transport. The article provides a general description of threats to ships related to weather conditions, loading methods or stability limitations. A statistical analysis of the occurrence of damage and/or loss of cargo from container ships was carried out and the risk of cargo loss was assessed on the basis of data from 2015‒2019. A Pareto diagram was used for this purpose. The authors present the concept of the container ship loading model, which may contribute to increasing the safety of shipping in the future.
随着集装箱海上运输的不断发展和集装箱船舶在设计和建造方面的变化,确保这种运输的适当安全水平是很重要的。几十年来,集装箱船的尺寸和载货能力一直在变化,其操纵限制和所需的稳定性标准也在变化。条例的改变、技术的发展和稳定性要求的增加似乎没有产生令人满意的结果- -集装箱船事故的原因继续显示出类似的模式。本文涉及确保海上集装箱运输安全的问题,特别侧重于货物过程。其目的是确定导致集装箱在海上灭失的因果关系,并开发一种可以显著提高集装箱运输安全水平的装载模型。这篇文章提供了与天气条件、装载方法或稳定性限制有关的对船舶的威胁的一般描述。根据2015-2019年的数据,对集装箱船舶货物损坏和/或灭失的发生情况进行了统计分析,并对货物灭失风险进行了评估。为此使用了帕累托图。提出了集装箱船装载模型的概念,对今后提高船舶的安全性有一定的帮助。
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引用次数: 0
Energy and Emission Quality Ranking of Newly Produced Low-Sulphur Marine Fuels 新生产的低硫船用燃料能源和排放质量排名
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-12-01 DOI: 10.2478/pomr-2022-0045
Z. Korczewski
Abstract The article describes the methodology of engine tests on new types of low-sulphur marine fuels in laboratory conditions in order to conduct a comprehensive assessment of their suitability for powering full-size marine engines. The innovativeness of the proposed solution consists of adapting the laboratory Diesel Engine Test Bed to carry out experimental tests using residual and alternative fuels so that it is possible to imitate the real operating conditions of the ship engine. The main aim of the research program was to assess the energy efficiency of six different low-sulphur marine fuels and their impact on the chemical emissivity of engine exhaust gases and air pollution with toxic and harmful chemical compounds. In order to achieve the research purpose formulated in this way, it was necessary to: (1) equip the constructed laboratory stand with highly specialised measuring equipment and (2) develop a technology for determining diagnostic parameters representing the basis for developing a ranking of the energy and emission quality of the tested marine fuels according to the proposed physical model. The model distinguishes 10 diagnostic parameters that, after normalisation, form two subsets of evaluation parameters - stimulant and destimulant. Determining their values made it possible to estimate a synthetic variable, according to which all the tested fuels were adjusted in the order from the “best” to the “worst”, in accordance with the adopted qualitative criteria of such an assessment. The results of the laboratory tests show that among the considered fuels, i.e., MDO, MGO, RMD 80/L, RMD 80/S, RME 180, and RMG 380 type, the best solution is to use MDO distillate fuel to power full-size marine engines. However, taking into account its high purchase price, a rational alternative decision is to choose RMG 380 type residual fuel, which ranks second in the ranking of the functional quality of the tested marine fuels.
摘要本文介绍了在实验室条件下对新型低硫船用燃料进行发动机试验的方法,以全面评估其是否适合为全尺寸船用发动机提供动力。所提出的解决方案的创新性包括调整实验室柴油发动机试验台,使用残余燃料和替代燃料进行实验测试,从而可以模拟船舶发动机的真实运行条件。该研究项目的主要目的是评估六种不同低硫船用燃料的能源效率及其对发动机废气化学发射率和有毒有害化合物的空气污染的影响。为了实现以这种方式制定的研究目的,有必要:(1)为建造的实验室支架配备高度专业化的测量设备;(2)开发一种用于确定诊断参数的技术,该技术代表了根据拟议的物理模型对测试的船用燃料的能量和排放质量进行排名的基础。该模型区分了10个诊断参数,这些参数在归一化后形成了两个子集的评估参数——刺激性和非刺激性。通过确定它们的值,可以估计一个综合变量,根据该变量,根据所采用的此类评估的定性标准,按照从“最佳”到“最差”的顺序调整所有测试燃料。实验室试验结果表明,在所考虑的燃料中,即MDO、MGO、RMD 80/L、RMD 80/S、RME 180和RMG 380型,最好的解决方案是使用MDO馏分燃料为全尺寸船用发动机提供动力。然而,考虑到其高昂的购买价格,一个合理的替代决定是选择RMG 380型剩余燃料,该燃料在测试船用燃料的功能质量排名中排名第二。
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引用次数: 13
Experimental Research of the Impact of Ship’s Rolling on the Performance of PV Panels 船舶横摇对光伏板性能影响的实验研究
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-12-01 DOI: 10.2478/pomr-2022-0051
W. Zeńczak, Z. Zapałowicz
Abstract The aim of the International Maritime Organization (IMO) to reduce by half the amount of greenhouse gases emitted by marine ships by 2050, and its vision of the fastest total decarbonisation in the maritime shipping industry within the present century, calls for implementation with various means of decarbonisation. The IMO approaches the process of decarbonisation in two phases. Firstly, short-term, compact projects are to be considered, next, more complex, medium- and long-term solutions should be aimed at. The preferred arrangements to be applied are photovoltaic systems. Their performance depends to a high degree on the solar incidence angle. In the case of a ship swinging as a result of its course in relation to the wave and incidence direction, the incidence angle undergoes significant periodic changes with a significant effect on the power generated by the PV panels. As a result, the total amount of energy produced by the PV panels diminishes. The paper presents experimental research results obtained on the stand that allowed the investigation of PV panels in simulated marine conditions. Two characteristic positions of a PV panel’s rotation axis in relation to the solar rays’ incidence direction were investigated. It was proved for both variants that the rolling period and solar incidence angle affected the power generated by the PV panel.
摘要国际海事组织(IMO)到2050年将船舶温室气体排放量减少一半的目标,以及其在本世纪内实现海运业最快全面脱碳的愿景,要求采用各种脱碳手段。国际海事组织将脱碳进程分为两个阶段。首先,应考虑短期、紧凑的项目,其次,应针对更复杂的中长期解决方案。首选的安排是光伏系统。它们的性能在很大程度上取决于太阳的入射角。在船舶因其相对于波浪和入射方向的航向而摆动的情况下,入射角会发生显著的周期性变化,对光伏电池板产生的功率产生显著影响。因此,光伏电池板产生的总能量减少。本文介绍了在模拟海洋条件下对光伏电池板进行研究的试验研究结果。研究了光伏电池板旋转轴相对于太阳光线入射方向的两个特征位置。事实证明,对于这两种变体,滚动周期和太阳入射角都会影响光伏电池板产生的功率。
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引用次数: 0
Autonomous Control of the Underwater Remotely Operated Vehicle in Collision Situation with Stationary Obstacle 水下遥控车辆与静止障碍物碰撞时的自主控制
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-12-01 DOI: 10.2478/pomr-2022-0043
R. Smierzchalski, Maciej Kapczyński
Abstract The article considers the problem of autonomous control of the underwater remotely operated vehicle mini Remotely Operated Vehicle (ROV) in a collision situation with a stationary obstacle. The control of the collision avoidance process is presented as a synthesis of fuzzy proportional-differential controllers for the control of distance and orientation concerning the detected stationary obstacle. The control of the submergence depth of the underwater vehicle has been adopted as a separate control flow. A method to obtain the main motion parameters of the underwater vehicle relative to the detected stationary obstacle using a Laser-based Vision System (LVS) and a pressure sensor coupled to an Inertial Measurement Unit (IMU) is described and discussed. The result of computer implementation of the designed fuzzy controllers for collision avoidance is demonstrated in simulation tests and experiments carried out with the mini ROV in the test pool.
摘要研究了水下遥控机器人(mini遥控机器人,ROV)在与静止障碍物碰撞情况下的自主控制问题。针对检测到的静止障碍物,将避碰过程的控制作为模糊比例微分控制器的综合,用于距离和方向的控制。水下航行器的沉深控制被作为一个单独的控制流。描述并讨论了一种利用激光视觉系统(LVS)和与惯性测量单元(IMU)耦合的压力传感器获取水下航行器相对于检测到的静止障碍物的主要运动参数的方法。通过仿真试验和小型ROV在试验池中的实验,验证了所设计的模糊避碰控制器的计算机实现结果。
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引用次数: 1
Flow Field Characteristic Analysis of Cushion System of Partial Air Cushion Support Catamaran in Regular Waves 规则波中部分气垫支撑双体船缓冲系统流场特性分析
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-09-01 DOI: 10.2478/pomr-2022-0024
Jinglei Yang, Hanbing Sun, Xiao-wen Li, Xin Liu
Abstract In order to study the flow field characteristics of cushion system of partial air cushion support catamaran (PACSCAT) in waves, an analysis was carried out involving flexible treatment on the bow and stern air seals to simulate air seal shape under test conditions by means of computational fluid dynamics method and fluid structure interaction (FSI) method. On this basis, the pressure conditions of the air cushion chamber and the pressurized chamber at different wavelengths and different speeds are studied and compared with experimental results. The experimental results show that: for the air cushion pressure, the nonlinear characteristics of the numerical calculation results are more subtle than the experimental values, after linear transformation, the amplitudes of the experimental values are obviously greater than the calculated values after linear transformation, but the average values are not much different; At low speed of 2.0m/s, the spatial pressure distribution of the pressurized chamber and the air cushion chamber are uniformly distributed, at high speed of 3.6m/s, except for a certain pressure jump occurred in the air cushion chamber near the stern air seal, the pressure in other spaces is also evenly distributed, it proves that the pressurized chamber type of air intake can effectively meet the air cushion pressure balance.
摘要为了研究部分气垫支撑双体船(PACSCAT)缓冲系统在波浪中的流场特性,采用计算流体力学方法和流固耦合(FSI)方法对船首和船尾气密封进行了柔性处理分析,模拟了试验条件下的气密封形状。在此基础上,对气垫腔和加压腔在不同波长、不同速度下的压力状况进行了研究,并与实验结果进行了比较。实验结果表明:对于气垫压力,数值计算结果的非线性特征比实验值更为微妙,线性变换后,实验值的幅值明显大于线性变换后的计算值,但平均值相差不大;低速2.0m/s时,增压室和气垫室空间压力分布均匀,高速3.6m/s时,除气垫室尾部气封附近出现一定的压力跳变外,其他空间压力分布均匀,证明增压室式进气口能有效满足气垫压力平衡。
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引用次数: 1
Assisted Propulsion Device of a Semi-Submersible Ship Based on the Magnus Effect 基于马格纳斯效应的半潜船辅助推进装置
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-09-01 DOI: 10.2478/pomr-2022-0023
Jing Lv, Yiqun Lin, Rui Zhang, Boyang Li, Hualin Yang
Abstract The purpose of this study is to explore the potentiality of wind propulsion on semi-submersible ships. A new type of Flettner rotor (two rotating cylinders) system installed on a semi-submersible ship is proposed. The structure and installation of two cylinders with a height of 20 m and a diameter of 14 m are introduced. The numerical simulation of the cylinder is carried out in Fluent software. The influence of apparent wind angle and spin ratio on the two cylinders are analysed, when the distance between two cylinders is 3D-13D (D is cylinder diameter). When the distance between two cylinders is 3D, the performance of the system increases with an increase in spin ratio. Moreover, the apparent wind angle also has an effect on the system performance. Specifically, the thrust contribution of the system at the apparent wind angle of 120° is the largest at the spin ratio of 3.0. The maximum thrust reaches 500 kN. When the spin ratio is 2.5 and the apparent wind angle is 120°, the maximum effective power of the system is 1734 kW. In addition, the influence of the two cylinders distance on system performance cannot be ignored. When the distance between the two cylinders is 7D and the spin ratio is 2.5, the effective power of the system reaches a maximum, which is 1932 kW.
摘要本研究的目的是探索风推进在半潜式船舶上的潜力。提出了一种安装在半潜船上的新型弗莱特纳转子(双旋转气缸)系统。介绍了高20米、直径14米的两缸的结构和安装。在Fluent软件中对气缸进行了数值模拟。分析了两缸间距为3D-13D (D为缸径)时,视风角和自旋比对两缸性能的影响。当两柱间距为3D时,系统性能随自旋比的增加而提高。此外,视风角对系统性能也有影响。其中,在视风角为120°时,自旋比为3.0时,系统的推力贡献最大。最大推力可达500kn。当自旋比为2.5,视风角为120°时,系统最大有效功率为1734 kW。此外,两缸距离对系统性能的影响也不容忽视。当两缸间距为7D,转速比为2.5时,系统有效功率达到最大,为1932 kW。
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引用次数: 0
Mathematical Modelling of Marine Power Plants with Thermochemical Fuel Treatment 采用热化学燃料处理的船用发电厂数学模型
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-09-01 DOI: 10.2478/pomr-2022-0030
Oleksandr Cherednichenko, S. Serbin, Mykhaylo Tkach, J. Kowalski, Daifen Chen
Abstract The article considers the methodological aspects of the theoretical investigation of marine power plants with thermochemical fuel treatment. The results of the study of the complex influence of temperature, pressure, and the ratio of steam / base fuel on the thermochemical treatment efficiency are presented. The adequacy of the obtained regression dependences was confirmed by the physical modelling of thermochemical fuel treatment processes. For a gas turbine power complex with a thermochemical fuel treatment system, the characteristics of the power equipment were determined separately with further merging of the obtained results and a combination of material and energy flow models. Algorithms, which provide settings for the mathematical models of structural and functional blocks, the optimisation of thermochemical energy transformations, and verification of developed models according to the indicators of existing gas turbine engines, were created. The influence of mechanical energy consumption during the organisation of thermochemical processing of fuel on the efficiency of thermochemical recuperation is analysed.
摘要本文考虑了采用热化学燃料处理的船用发电厂理论研究的方法论方面。给出了温度、压力和蒸汽/基础燃料比对热化学处理效率的复杂影响的研究结果。热化学燃料处理过程的物理模型证实了所获得的回归相关性的充分性。对于具有热化学燃料处理系统的燃气轮机动力综合体,通过进一步合并所获得的结果以及材料流和能量流模型的组合,分别确定了动力设备的特性。创建了算法,为结构和功能块的数学模型提供设置,优化热化学能量转换,并根据现有燃气轮机发动机的指标验证开发的模型。分析了燃料热化学处理组织过程中的机械能耗对热化学回收效率的影响。
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引用次数: 4
An Improved Dynamic Surface Sliding Mode Method for Autonomous Cooperative Formation Control of Underactuated USVS with Complex Marine Environment Disturbances 复杂海洋环境扰动下欠驱动usv自主协同编队控制的改进动态表面滑模方法
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-09-01 DOI: 10.2478/pomr-2022-0025
Zaopeng Dong, Shijie Qi, Min Yu, Zheng Zhang, Haisheng Zhang, Jiakang Li, Yang Liu
Abstract In this paper, a novel dynamic surface sliding mode control (DSSMC) method, combined with a lateral velocity tracking differentiator (LVTD), is proposed for the cooperative formation control of underactuated unmanned surface vehicles (USVs) exposed to complex marine environment disturbances. Firstly, in view of the kinematic and dynamic models of USVs and the design idea of a virtual control law in a backstepping approach, the trajectory tracking control problem of USVs’ cooperative formation is transformed into a stabilisation problem of the virtual control law of longitudinal and lateral velocities. Then, aiming at the problem of differential explosion caused by repeated derivation in the process of backstepping design, the first-order low-pass filter about the virtual longitudinal velocity and intermediate state quantity of position is constructed to replace differential calculations during the design of the control law, respectively. In order to reduce the steady-state error when stabilising the virtual lateral velocity control law, the integral term is introduced into the design of the sliding mode surface with a lateral velocity error, and then the second-order sliding mode surface with an integral is structured. In addition, due to the problem of controller oscillation and the role of the tracking differentiator (TD) in active disturbance rejection control (ADRC), the LVTD is designed to smooth the state quantity of lateral velocity. Subsequently, based on the dynamic model of USV under complex marine environment disturbances, the nonlinear disturbance observer is designed to observe the disturbances and compensate the control law. Finally, the whole cooperative formation system is proved to be uniformly and ultimately bounded, according to the Lyapunov stability theory, and the stability and validity of the method is also verified by the simulation results.
提出了一种结合横向速度跟踪微分器(LVTD)的新型动态表面滑模控制(DSSMC)方法,用于欠驱动无人水面航行器(usv)在复杂海洋环境扰动下的协同编队控制。首先,根据usv的运动学和动力学模型以及退步法虚拟控制律的设计思想,将usv协同编队的轨迹跟踪控制问题转化为纵向和横向速度虚拟控制律的稳定问题;然后,针对反推设计过程中由于反复求导导致的差分爆炸问题,分别构建了关于虚拟纵向速度和位置中间状态量的一阶低通滤波器来代替控制律设计中的微分计算。为了减小虚拟横向速度控制律稳定化时的稳态误差,将积分项引入到具有横向速度误差的滑模曲面设计中,构造了具有积分的二阶滑模曲面。此外,针对控制器振荡问题和跟踪微分器在自抗扰控制中的作用,设计LVTD平滑横向速度的状态量。随后,基于复杂海洋环境扰动下无人潜航器的动力学模型,设计了非线性扰动观测器来观测扰动并补偿控制律。最后,根据Lyapunov稳定性理论证明了整个协同编队系统是一致且最终有界的,仿真结果也验证了该方法的稳定性和有效性。
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引用次数: 4
Influence of Material Thickness on the Ductile Fracture of Steel Plates for Shipbuilding 材料厚度对造船用钢板韧性断裂的影响
IF 2 3区 工程技术 Q2 Engineering Pub Date : 2022-09-01 DOI: 10.2478/pomr-2022-0036
J. Kowalski, J. Kozák
Abstract In the shipbuilding industry, the risk of brittle fractures is relatively high because some units operate in arctic or subarctic zones and use high thickness (up to 100 mm) steel plates in their structures. This risk is limited by employing certified materials with a specific impact strength, determined using the Charpy method (for a given design temperature) and by exercising control over the welding processes (technology qualification, production supervision, and non-destructive tests). However, for offshore constructions, such requirements may prove insufficient. For this reason, regulations employed in constructing offshore structures require conducting crack tip opening displacement (CTOD) tests for steel and welded joints with thicknesses exceeding 40 mm for high tensile strength steel and 50 mm for other steel types. Since classification codes do not accept the results of CTOD tests conducted on specimens of sub-sized dimensions, the problem of theoretically modelling the steel construction destruction process is of key importance, as laboratory tests for notched elements of considerable thickness (100 mm and higher) are costly and problems stemming from high loads and a wide range of recorded parameters are not uncommon. The aim of this research is to find a relationship between material thickness and CTOD value, by establishing and verifying a numerical model that allows recalculating a result obtained on a sub-size specimen to a full- size specimen for a ductile fracture mode. This work presents results and conclusions from numerical modelling and compares them with laboratory test results of the elastic-plastic properties of high thickness steel, typically used in offshore applications.
在造船业中,脆性断裂的风险相对较高,因为一些单位在北极或亚北极地区作业,并在其结构中使用高厚度(高达100毫米)钢板。通过采用具有特定冲击强度的认证材料(使用Charpy方法确定(给定设计温度))以及通过对焊接过程(技术鉴定、生产监督和无损检测)进行控制,可以限制这种风险。然而,对于近海建筑来说,这样的要求可能是不够的。因此,在建造海上结构时所采用的法规要求对钢和焊接接头进行裂纹尖端张开位移(CTOD)测试,高抗拉强度钢的厚度超过40毫米,其他钢类型的厚度超过50毫米。由于分类规范不接受对亚尺寸试件进行的CTOD试验的结果,因此对钢结构破坏过程进行理论建模的问题至关重要,因为对相当厚(100毫米及以上)的缺口构件进行实验室试验成本高昂,而且由于高载荷和记录参数范围广泛而产生的问题并不罕见。本研究的目的是通过建立和验证一个数值模型来发现材料厚度与CTOD值之间的关系,该模型允许将在亚尺寸试件上获得的结果重新计算到塑性断裂模式的全尺寸试件上。这项工作提出了数值模拟的结果和结论,并将其与高厚度钢弹塑性性能的实验室测试结果进行了比较,高厚度钢通常用于海上应用。
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引用次数: 0
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Polish Maritime Research
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