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1
Content available Review of the seakeeping characteristics of trimaran, catamaran, and SWATH ships
Majdfar Sohrab, Ghassemi Hassan, Ashkezari Abbas Zarenezhad, He Guanghua
Zeszyty Naukowe Politechniki Morskiej w Szczecinie
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2025
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nr 83 (155)
32--50
EN
Seakeeping constitutes a fundamental component of marine engineering, which significantly affects the safety, comfort, and operational efficacy of maritime vessels. This paper presents an exhaustive examination of the seakeeping attributes associated with three categories of multihull vessels: trimarans, catamarans, and small waterplane area twin hull (SAWTH) vessels. The investigation delves into the distinctive design merits of these vessels, which include improved stability, velocity, and adaptability, rendering them appropriate for a variety of maritime uses. Through a meticulous evaluation of motion responses such as heave, pitch, and roll, this work elucidates the hydrodynamic performance of each vessel category under varying sea states. Sophisticated computational techniques, such as computational fluid dynamics (CFD), boundary element method (BEM), and hybrid numerical methodologies, are utilized to enhance hull configurations and augment seakeeping capabilities. By integrating insights from a multitude of studies, this review emphasizes the increasing significance of multihull vessels in contemporary maritime operations and offers crucial perspectives for prospective research and design refinement.
2
Content available Numerical study of the hydrodynamic performance of rim-driven propulsion featuring a modified 19A duct
Masoumpour Meysam, Ghassemi Hassan, Mousavizadegan S. Hossein, He Guanghua
Polish Maritime Research
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2025
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nr 3
100--117
EN
The rim-driven propeller (RDP) is an innovative propulsion system that is primarily used in underwater Vehicles and the bow thrusters of ships. In this study, the Reynolds-averaged Navier-Stokes (RANS) equations are employed together with the moving reference frame method and steady-state numerical simulations to address challenges related to applicability. The SST turbulence model is also incorporated. Initially, a Ka-Series+19A ducted propeller (DP) is considered, and the numerical results for its hydrodynamic performance are found to show a close correlation with experimental data. Notably, the thrust coefficient of the duct at low advance coefficients is high, indicating that the duct can operate efficiently under heavy load conditions. The study then focuses on the RDP, which uses the same propeller but features a distinct duct design due to its rim-driven configuration. The hydrodynamic open-water characteristics of the RDP are obtained and compared with those of the DP. The results reveal that the RDP has lower efficiency than the DP, primarily due to the gap and the presence of the rotor in the RDP. Furthermore, a detailed analysis of the pressure distribution on the surfaces of the blade and duct is presented, as well as the velocity and pressure contours at various downstream positions for both the DP and RDP. Particular attention is paid to the flow gap between the propeller and duct, along with the associated turbulence intensity.
3
Content available Hydrodynamic characteristics of the Pusher, Tractor and Schottel types of the AZIPOD propulsion system
Gholami Hossein, Ghassemi Hassan, He Guanghua, Shamsi Reza
Polish Maritime Research
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2024
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nr 4
21--30
EN
The main purpose of this paper is to investigate the hydrodynamics performance of the three types (pusher, tractor and Schottel) of the azimuthing podded drive (AZIPOD) electric propulsion system. To evaluate the propulsive performance of the podded drive system, the Reynolds-Averaged Navier Stokes (RANS) solver is employed. KP-505 propeller as the research object, hydrodynamic open-water characteristics of this propeller was first calculated, and agreed well with test results. Then, numerical simulation of the thrust, torque and efficiency of the three types of the AZIPOD systems (Pusher, Tractor and Schottel) with KP-505 propeller at various yaw angles (from -30° to +30° with 15° increments) and different advance coefficients were compared. For the Schottel propulsion system, the effects of the number of propeller blades and the blade pitch-diameter ratio on performance are presented and discussed. Finally, the effect of sturt, support element and pod for pusher type on the pressure coefficient, thrust and torque of one blade and whole blades is investigated during one cycle.
4
Content available Effect of various duct shapes and blade sections on the efficiency performance of horizontal axis tidal current turbine
Gandomani Mahdi Azimi, Ghassemi Hassan, He Guanghua
Polish Maritime Research
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2024
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nr 4
59--68
EN
This research emphasizes the importance of optimal design for tidal turbines under various ducts and blade sections to enhance efficiency. A Reynolds-Averaged Navier-Stokes (RANS) solver with turbulence model is used to investigate the performance of horizontal-axis tidal current turbines (HATCT) under different ducts and blade sections. Analyses were conducted using various meshes and, in several stages, to ensure the accuracy of the results. Six types of different blades sections and winglets are selected and the numerical results of thrust, torque and power coefficients are compared. demonstrating the accepTable accuracy of this analytical method. It is indicated that the effect of the winglet caused to increase the power coefficient. The numerical results were compared and validated with experimental data and found in good agreement. Finally, the effect of the different duct shapes with turbine type 1 at TSR = 5 is obtained with significant results of the power coefficient.
5
Content available Investigating the harbour basin tranquillity in the Genaveh Port development plan
Sharif Mahdi Bandizadeh, Gorbanpour Amir Hossein, Ghassemi Hassan, He Guanghua
Polish Maritime Research
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2023
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nr 1
145--155
EN
The Genaveh commercial port was placed on the agenda of the Iranian PMO (ports and maritime organization) to consider economic, commercial and residential development in Bushehr province and specifically in Genaveh city. In order to increase the water capacity of the port, it is necessary to build a new harbour basin for exploitation and commercial purposes at a depth of 5 to 6 meters by extending the existing jetties arms in front of the port. This research aims to investigate the harbour basin’s tranquillity for providing vessels with safe berthing. For this purpose, three modules, namely the flow model (FM), spectral wave (SW) and Boussinesq waves model (BW) from the MIKE 21 software package, were utilized. According to the monitoring data, which is provided by the Iranian PMO, the harbour basin’s tranquillity based on the prevailing wave directions was investigated. Based on the diffraction graph in the harbour basin, the results showed that, according to the percentage of permissible diffraction recommended by different valid regulations, there is a need to modify the geometry of the breakwater arms to increase the harbour basin’s tranquillity at the port in the development plan.
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