Article
Engineering, Aerospace
Mehmet Seyhan, Mustafa Sarioglu, Yahya E. Akansu
Summary: The experimental results show that NACA0015 airfoil models with leading-edge tubercles do not experience a sudden loss of lift in the poststall regime and exhibit higher lift coefficients. Among them, the W15 model performs the best in terms of maximum lift coefficient, stall angle, aerodynamic performance (C-L/C-D), and the minimum fluctuating lift coefficient in both pre- and poststall regimes.
Article
Engineering, Marine
Chao Deng, Haibo Wang, Zhanxia Feng, Zhongqiang Zheng, Zhaohua Wang, Zongyu Chang
Summary: This paper analyzes the impact of the rotation control method of the hydrofoil on the propulsion performance of wave-powered boats, establishes an equivalent instantaneous optimization model, and verifies the feasibility of active control when considering ocean currents.
Article
Physics, Multidisciplinary
Hamed Saffarzadeh, Mohammad Hassan Djavareshkian
Summary: In this study, thermal Lattice Boltzmann Technique combined with the Ghost Fluid method was used to simulate the flow and heat transfer rate around a NACA 0015 airfoil in the presence of an external magnetic field source. The effects of Hartmann and Reynolds numbers, magnetic field angle, and airfoil attack angle on flow and heat transfer characteristics were investigated. The results showed that with an increase in the Reynolds number, the drag and lift coefficients decrease while the Nusselt number increases, and the total entropy generation rate of the system reaches a maximum around gamma = 60.
Article
Multidisciplinary Sciences
Sergey G. Skripkin, Mikhail A. Tsoy, Aleksandra Yu Kravtsova
Summary: An experimental study was conducted on the cavitating behavior of a NACA0012 hydrofoil with an aspect ratio of 0.02 in a slit channel. High-speed visualization technique with a sampling rate of over 100 kHz was used to investigate the formation and development of cavities in a quasi-two-dimensional turbulent flow. The most energetic modes of unsteady cavitation flow were identified using dynamic mode decomposition, revealing the presence of second and third modes for the first time. Experimental data on the reverse motion of the vapor-gas mixture into the inner region of supercavitation were also presented.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Marine
Kwan-Woo Kim, Ju-Han Lee, Kwang-Jun Paik, Weoncheol Koo, Young-Gyu Kim
Summary: This study investigates the propagation of internal waves in a two-layer stratified flow generated by a hydrofoil using a CFD model. The results suggest that the VOF model provides better agreement with experimental data compared to the mixture model.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART M-JOURNAL OF ENGINEERING FOR THE MARITIME ENVIRONMENT
(2021)
Article
Computer Science, Information Systems
Shahzad Ali, Faraz Ahmad, Muhammad Hassan, Zabdur Rehman, Abdul Wadood, Khurshid Ahmad, Herie Park
Summary: In this study, hydrofoil ribs made from NACA 2412 profile were mounted in a novel way at all walls of microchannel heat sink to improve its thermo-hydraulic characteristics. Different configurations were tested, and it was found that the best performance is achieved when rib spacing becomes equal to cord length. The study also showed that staggered configuration outperformed aligned configuration.
Article
Engineering, Marine
J. Zhao, R. C. Zhu, W. J. Zhou
Summary: An efficient velocity decomposition method for simulating free surface flows on the OpenFOAM platform has been proposed, which treats the free surface as a source region and models it using the volume-of-fluid method. The method shows similar accuracy to traditional CFD methods but with lower sensitivity to domain size.
Article
Engineering, Marine
Zongyu Chang, Chao Deng, Zhanxia Feng, Jia Chen, Zhongqiang Zheng, Yang Zhang
Summary: This paper investigates the propulsion performance of a wave-powered vehicle by actively controlling the rotation angle of hydrofoil. It is found that the rotation angle is a key element that affects the propulsive force, and wave-powered vehicles with active controlling hydrofoils demonstrate superior propulsion performance compared to those with restoring springs. The proposed results offer valuable insights for improving the design of such vehicles.
Article
Mathematics, Applied
Tarek Ghoudi, M. Shadi Mohamed, Mohammed Seaid
Summary: A new adaptive finite volume method is proposed for the simulation of wave problems in the time domain. The method discretizes the transient wave equations in time and space, and utilizes a vertex-centered finite volume method with both cell-centered and edge-midpoint. The method also includes a mesh adaptation procedure based on energy-norm error-estimates, allowing for multiple adaptations within a single error estimation.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2023)
Article
Computer Science, Interdisciplinary Applications
Veit Krause, Axel Voigt
Summary: In this paper, we investigate the simulation of fluid deformable surfaces using surface finite elements and a semi-implicit time stepping scheme. The surface is modeled by incompressible surface Navier-Stokes equations with bending forces, and conservation of the enclosed volume is enforced. The numerical approach includes higher order surface parameterizations, a Taylor-Hood element for the surface Navier-Stokes part, appropriate approximations of the geometric quantities of the surface, mesh redistribution, and a Lagrange multiplier for the constraint. Computational examples illustrate the solid-fluid duality of fluid deformable surfaces and demonstrate optimal convergence properties for different sub-problems.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Engineering, Marine
Zao Ni, Manhar Dhanak, Tsung-chow Su
Summary: The study investigates the performance of a NACA 63(4)-021 hydrofoil in motion under and in close proximity of a free surface. Results show that the interaction between the hydrofoil-motion induced waves on the free surface and the hydrofoil can mitigate flow separation characteristics and delay stall, resulting in improved hydrofoil performance. Significant increase in maximum lift coefficient and overall performance improvement are observed, but there is a decrease in lift-to-drag ratio at lower angles of attack.
INTERNATIONAL JOURNAL OF NAVAL ARCHITECTURE AND OCEAN ENGINEERING
(2021)
Article
Engineering, Marine
Hongqiang Sang, Gang Liu, Xiujun Sun, Can Li, Lei Wang, Liwei Wang
Summary: This study analyzes the propulsive performance of wave gliders using submerged passive flapping hydrofoils. A numerical model and experiments were conducted to verify the accuracy of the model. The results showed that the speed fluctuation of the hydrofoil decreased with increasing wave frequency, and there was an optimal spring constant to maximize the navigation speed under different wave frequencies.
Article
Computer Science, Interdisciplinary Applications
Junxiang Yang, Zhijun Tan, Sangkwon Kim, Chaeyoung Lee, Soobin Kwak, Junseok Kim
Summary: This study presents a method for simulating fluid flows on curved surfaces in three-dimensional space. By using the finite volume lattice Boltzmann method and unstructured triangular meshes, the proposed method offers an efficient solution for fluid flows on curved surfaces.
ENGINEERING WITH COMPUTERS
(2022)
Article
Engineering, Marine
S. Zhang, B. C. Khoo, A-M Zhang
Summary: This study established a compressible, three-dimensional air-gun bubble model in OpenFOAM using finite volume and volume of fluid methods to investigate the characteristics of air-gun bubble pulsation and surrounding flow-field pressures produced by various opening areas and forms. The study quantitatively analyzed the maximum horizontal bubble displacement, main primary pulse, and bubble pulse, revealing that different air-gun opening areas result in variations in bubble expansion and collapse times and lead to different bubble shapes during the pulsation cycle. The system with the largest airgun opening area had the largest pressure wave primary pulse.
Article
Engineering, Marine
Hongdan Liu, Yunxing Fu, Bing Li
Summary: This article proposes a joint control method LQRY-SMC for the longitudinal motion control of hydrofoil craft. By combining linear-quadratic optimal control with output regulation and sliding-mode control, and optimizing the parameters using genetic algorithm, the method improves control stability and reduces heave displacement and pitch angle under turbulent flow. The simulation results show the effectiveness and superiority of the proposed method.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
Bijoy Prasad, Takanori Hino, Kazuo Suzuki
Article
Engineering, Marine
S. M. Rashidul Hasan, Md Mashud Karim
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART M-JOURNAL OF ENGINEERING FOR THE MARITIME ENVIRONMENT
(2020)
Article
Engineering, Marine
S. M. Rashidul Hasan, Md Mashud Karim
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2020)
Article
Engineering, Marine
Md Daluar Hussain, Md Mashud Karim, Noriyuki Sasaki
Summary: Several energy-saving methods have been implemented on ships, including the Gate Rudder System, which can reduce fuel consumption by up to 14%. This research investigates the propulsive performance of a cargo ship with a gate rudder system and observes scale effects, showing that larger models generate more thrust compared to smaller ones.
Article
Multidisciplinary Sciences
S. M. Rashidul Hasan, Md. Mashud Karim
Summary: To establish correct EEDI baselines for inland ships of Bangladesh, it is crucial to verify accurate ship data. Using verified ships' physical and operational data, proposed EEDI baselines for Inland Cargo, Oil Tanker and Passenger Ships of Bangladesh in this research.
Article
Engineering, Marine
S. M. Rashidul Hasan, Md Mashud Karim
Summary: This study revised the Energy Efficiency Design Index (EEDI) for inland ships in Bangladesh and incorporated the shallow water effect through actual measurements. The results of Schlichting's method were compared with other methods and found to have higher deviations. The analysis of Bangladesh's inland ships also overcame the problem of assuming ship data by conducting physical investigations and obtaining accurate results.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART M-JOURNAL OF ENGINEERING FOR THE MARITIME ENVIRONMENT
(2023)
Article
Engineering, Marine
Md. Mashud Karim, Nabila Naz
JOURNAL OF MARINE SCIENCE AND APPLICATION
(2019)
Proceedings Paper
Engineering, Mechanical
Md. Mashud Karim, Mahmudur Rahman, Md. Abdul Hai, Md. Masuduzzaman Shimul, Saif Hossain Sudhi
PROCEEDINGS OF THE 12TH INTERNATIONAL CONFERENCE ON MECHANICAL ENGINEERING (ICME 2017)
(2018)
Proceedings Paper
Engineering, Marine
Md. Mashud Karim, Nabila Naz
10TH INTERNATIONAL CONFERENCE ON MARINE TECHNOLOGY (MARTEC 2016)
(2017)
Proceedings Paper
Engineering, Marine
Md. Mashud Karim, S. M. Rashidul Hasan
10TH INTERNATIONAL CONFERENCE ON MARINE TECHNOLOGY (MARTEC 2016)
(2017)
Proceedings Paper
Engineering, Marine
Md. Ariful Hoque, Md. Mashud Karim, Aevelina Rahman
10TH INTERNATIONAL CONFERENCE ON MARINE TECHNOLOGY (MARTEC 2016)
(2017)
Proceedings Paper
Engineering, Marine
Nafis Fuad, Mohammad Kifayath Chowdhury, Mohammad Salman Yasin, Md. Mashud Karim
10TH INTERNATIONAL CONFERENCE ON MARINE TECHNOLOGY (MARTEC 2016)
(2017)
Article
Thermodynamics
N. Mostafa, M. M. Karim, M. M. A. Sarker
JOURNAL OF APPLIED FLUID MECHANICS
(2016)
Article
Engineering, Marine
Alba Ricondo, Laura Cagigal, Beatriz Perez-Diaz, Fernando J. Mendez
Summary: This research presents a site-specific metamodel based on the SWASH numerical model simulations, which can predict coastal hydrodynamic variables in a fast and efficient manner. The metamodel uses downscaled and dimensionality reduced synthetic database to accurately reproduce wave setup, wave heights associated with different frequency bands, and wave runup. This method has great potential in coastal risk assessments, early warning systems, and climate change projections.
Article
Engineering, Marine
Xiao Yu, Wangjun Ren, Bukui Zhou, Li Chen, Xiangyun Xu, Genmao Ren
Summary: This study investigated and compared the compression responses and energy absorption capacities of coral sand and silica sand at a strain rate of approximately 1000 s-1. The results showed that coral sand had significantly higher energy absorption capacity than silica sand due to its higher compressibility. The study findings suggest that using poorly graded coral sand can improve its energy absorption capacity.
Article
Engineering, Marine
Jingxi Zhang, Junmin Mou, Linying Chen, Pengfei Chen, Mengxia Li
Summary: This paper proposes a cooperative control scheme for ship formation tracking based on Model Predictive Control. A predictive observer is designed to estimate the current motion states of the leader ship using delayed motion information. Comparative simulations demonstrate the effectiveness and robustness of the proposed controller.
Article
Engineering, Marine
Yu Yao, Danni Zhong, Qijia Shi, Ji Wu, Jiangxia Li
Summary: This study proposes a 2DH numerical model based on Boussinesq equations to investigate the impact of dredging reef-flat sand on wave characteristics and wave-driven current. The model is verified through wave flume experiments and wave basin experiments, and the influences of incident wave conditions and pit morphological features on wave characteristics are examined.
Article
Engineering, Marine
Jayanta Shounda, Krishnendu Barman, Koustuv Debnath
Summary: This study investigates the double-average turbulence characteristics of combined wave-current flow over a rough bed with different spacing arrangements. The results show that a spacing ratio of p/r=4 offers the highest resistance to the flow, and the double-average Reynolds stress decreases throughout the flow depth. The advection of momentum-flux of normal stress shows an increase at the outer layer and a decrease near the bed region after wave imposition. Maximum turbulence kinetic energy production and diffusion occur at different layers. The turbulence structure is strongly anisotropic at the bottom region and near the outer layer, with a decrease in anisotropy observed with an increase in roughness spacing.
Article
Engineering, Marine
Meng Zhang, Lianghui Sun, Yaoguo Xie
Summary: The research proposes a method for online identification of wave bending and torsional moment in hull structures. For structures without large openings, the method optimizes sensor positions and establishes a mathematical model to improve accuracy. For structures with large openings, a joint dual-section monitoring method is proposed to simultaneously identify bending and torsional moments in multiple key cross sections.
Article
Engineering, Marine
Longming Chen, Shutao Li, Yeqing Chen, Dong Guo, Wanli Wei, Qiushi Yan
Summary: This study investigated the dynamic response characteristics and damage modes of pile wharves subjected to underwater explosions. The results showed that the main damaged components of the pile wharf were the piles, and inclined piles had a higher probability of moderate or more significant damage compared to vertical piles. The study also suggested that replacing inclined piles with alternative optimized structures benefits the blast resistance of pile wharves.
Article
Engineering, Marine
I. -C Kim, G. Ducrozet, V. Leroy, F. Bonnefoy, Y. Perignon, S. Bourguignon
Summary: Previous research focused on the accuracy and efficiency of short-term wave fields in specific prediction zones, while we developed algorithms for continuous wave prediction based on the practical prediction zone and discussed important time factors and strategies to reduce computational costs.
Article
Engineering, Marine
Hang Xie, Xianglin Dai, Fang Liu, Xinyu Liu
Summary: This study investigates the load characteristics of a three-dimensional stern model with pitch angle through a drop test, and reveals complex characteristics of pressure distribution near the stern shaft. The study also shows that the vibration characteristics of the load are influenced by the drop height and pitch angle, with the drop height having a greater effect on the high-frequency components.
Article
Engineering, Marine
Hangyuan Zhang, Wanli Yang, Dewen Liu, Xiaokun Geng, Wangyu Dai, Yuzhi Zhang
Summary: The deep-water bridge is more vulnerable to earthquake damage than the bridge standing in air. The larger blocking ratio has a significant impact on the added mass coefficient, which requires further comprehensive study. The generation mechanism of block effect is analyzed using numerical simulation software ANSYS Fluent. The results show that the recirculation zone with focus reduces the pressure on the back surface of the cylinder, resulting in the peak value of in-line force not occurring synchronously with the peak value of acceleration. The change in position and intensity of the recirculation zone with focus, as well as the change in water flow around the cylinder surface, are identified as the generation mechanism of the block effect, which has a 10% influence on the hydrodynamic force. The changing rule of the added mass coefficient with blocking ratio is discussed in detail, and a modification approach to the current added mass coefficient calculation method is suggested. Physical experiments are conducted to validate the modification approach, and the results show that it is accurate and can be used in further study and real practice.
Article
Engineering, Marine
Golnesa Karimi-Zindashti, Ozgur Kurc
Summary: This study examines the performance of an in-house code utilizing a deterministic vortex method on the rotation of circular and square cylinders. The results show that rotational motion reduces drag forces, suppresses fluctuating forces, and increases lift forces. The code accurately predicts vortex shedding suppression and identifies the emergence of near-field wakes in the flow over rotating square cylinders.
Article
Engineering, Marine
George Dafermos, George Zaraphonitis
Summary: The survivability of damaged ships is of great importance and the regulatory framework is constantly updated. The introduction of the probabilistic damage stability framework has rationalized the assessment procedure. Flooding simulation tools can be used to investigate the dynamic response of damaged ships.
Article
Engineering, Marine
Xuyue Chen, Xu Du, Chengkai Weng, Jin Yang, Deli Gao, Dongyu Su, Gan Wang
Summary: This paper proposes a real-time drilling parameters optimization method for offshore large-scale cluster extended reach drilling based on intelligent optimization algorithm and machine learning. By establishing a ROP model with long short-term memory neurons, and combining genetic algorithm, differential evolution algorithm, and particle swarm algorithm, the method achieves real-time optimization of drilling parameters and significantly improves the ROP.
Article
Engineering, Marine
Sung-Jae Kim, Chungkuk Jin, MooHyun Kim
Summary: This study investigates the dynamic behavior of a moored submerged floating tunnel (SFT) under tsunami-like waves through numerical simulations and sensitivity tests. The results show that design parameters significantly affect the dynamics of the SFT system and mooring tensions, with shorter-duration and higher-elevation tsunamis having a greater impact.
Article
Engineering, Marine
G. Clarindo, C. Guedes Soares
Summary: Environmental contours are constructed using the Inverse-First Order Reliability Method based on return periods. The paper proposes the use of the Burr distribution to model the marginal distribution of long-term significant wave heights. The newly implemented scheme results in different environmental contours compared to the reference approach.
