Experimental study of spoiler influence to delta wing generated vortex in water towing tank

2012 ◽  
Author(s):  
Junwei Wang ◽  
Jinwen Yang ◽  
Zhirong Liu ◽  
Yi He ◽  
Feng Bao
Keyword(s):  
Experimental Study ◽  
Delta Wing ◽  
Towing Tank

Study on vertical motion reduction of a trimaran based on collaborative controlled appendages

2020 ◽  
Vol 17 (6) ◽  
pp. 172988142097677
Author(s):  
Zhilin Liu ◽  
Linhe Zheng ◽  
Guosheng Li ◽  
Shouzheng Yuan ◽  
Songbai Yang
Keyword(s):  
Experimental Study ◽  
Vertical Motion ◽  
Model Tests ◽  
Wave Period ◽  
Regular Waves ◽  
Towing Tank ◽  
Vertical Stability ◽  
Stabilization Control ◽  
Stability Performance

In recent years, the trimaran as a novel ship has been greatly developed. The subsequent large vertical motion needs to be studied and resolved. In this article, an experimental study for a trimaran vertical stabilization control is carried out. Three modes including the bare trimaran (the trimaran without appendages, the trimaran with fixed appendages, and the trimaran with controlled appendages) are performed through model tests in a towing tank. The model tests are performed in regular waves. The range of wave period is 2.0–4.0 s, and the speed of the carriage is 2.93 and 6.51 m/s. The results of the three modes show the fixed appendages and the actively controlled appendages are all effective for the vertical motion reduction of the trimaran. Moreover, the controlled appendages are more effective for the vertical stability performance of the trimaran.

Experimental Study of a Tanker Ship Squat in Shallow Water

2014 ◽  
Vol 66 (2) ◽  
Author(s):  
Mohammadreza Fathi Kazerooni ◽  
Mohammad Saeed Seif
Keyword(s):  
Experimental Study ◽  
Shallow Water ◽  
Experimental Approach ◽  
Model Tests ◽  
Ship Hull ◽  
Experimental Results ◽  
Shallow Waters ◽  
Towing Tank ◽  
Ship Model

One of the phenomena restricting the tanker navigation in shallow waters is reduction of under keel clearance in the terms of sinkage and dynamic trim that is called squatting. According to the complexity of flow around ship hull, one of the best methods to predict the ship squat is experimental approach based on model tests in the towing tank. In this study model tests for tanker ship model had been held in the towing tank and squat of the model are measured and analyzed. Based on experimental results suitable formulae for prediction of these types of ship squat in fairways are obtained.

Experimental Study of the Effect of the Pontoon Presence on the Flow-Induced Motion of a Semi-Submersible Platform With Four Square Columns

2019 ◽  
Author(s):  
Rodolfo T. Gonçalves ◽  
Hideyuki Suzuki ◽  
Fredi Cenci ◽  
André L. C. Fujarra ◽  
Shinichiro Hirabayashi
Keyword(s):  
Experimental Study ◽  
Fatigue Life ◽  
Transverse Direction ◽  
The Other ◽  
Mooring Line ◽  
Towing Tank ◽  
Spacing Ratio ◽  
Floating System ◽  
Induced Motion ◽  
Four Square

Abstract The Flow-Induced Motions (FIM) is an essential topic on multi-column platforms due to the effect on the mooring line fatigue life. Vortex-Induced Motions (VIM) or galloping behavior can be observed for an array of four columns with square sections. The presence of pontoons showed to be important for changing the flow around the array and promote different amplitude behavior of the motions in the transverse direction mainly. This article aims to understand the effect of the presence of two pontoons on the FIM of a semi-submersible platform (SS) with four columns and square sections. Model tests of a floating system supported elastically utilizing four springs were performed in a towing tank. Five different pontoon ratios were tested, namely P/L = 0, 0.25, 0.50, 0.75 and 1.00; where P is the pontoon height, and L is the length of the square column face. The draft condition was kept constant as H/L = 1.5; where H is the draft of the platform. The spacing ratio of the columns was S/L = 4; where S is the distance between column centers. Three incidence angles of the current were carried out, i.e., 0-deg incidence represents the condition in which the two pontoons are aligned to the current, 45-deg incidence represents the non-symmetric condition in which the pontoons are 45 degrees positioned to the current, and 90-deg incidence represents the condition in which the two pontoons are perpendicular to the current. The transverse amplitudes decreased with increasing the pontoon ratio for 0 and 45-deg incidences. On the other hand, the transverse amplitudes increased with increasing the pontoon ratio for 90-deg incidence. The pontoon presence needs to be well investigated to choose the best condition to avoid raising the FIM.

An experimental study of the spanwise correlation of vortex shedding in the towing tank

2012 ◽  
Vol 8 (5) ◽  
pp. 517-523 ◽  
Author(s):  
Jijun Gu ◽  
Waldir T. Pinto ◽  
Carlos Levi ◽  
Menglan Duan
Keyword(s):  
Experimental Study ◽  
Vortex Shedding ◽  
Towing Tank

scholarly journals Gaya Hambat Saat Hidro Planing dan Gaya Angkat Aerodinamika Saat Cruise di Efek Permukaan pada Pesawat Wing in Surface Effect

WARTA ARDHIA ◽  
2017 ◽  
Vol 42 (2) ◽  
pp. 71
Author(s):  
Sayuti Syamsuar
Keyword(s):  
Surface Effect ◽  
Delta Wing ◽  
The Body ◽  
Test Model ◽  
Towing Tank ◽  
Ansys Cfx ◽  
Effect Theory ◽  
Towing Tank Test ◽  
Hydrodynamic Wave ◽  
Aerodynamic Lift

Perhitungan komputasional dinamika fluida pada model 3 Dimensi pada pesawat Wung In Surface Effect sangat penting untuk mengetahui data hasil uji towing tank dan uji terbang. Konfigurasi Lippisch mempunyai sayap berbentuk inverse delta dan punuk di atasnya menggunakan airfoil jenis Clark Y yang telah dirancang untuk memenuhi karakteristik efek permukaan. Piranti lunak pertama Maxsurf digunakan untuk membandingkan hasil uji model towing tank saat fase hydro planing. Piranti lunak kedua ANSYS CFX digunakan untuk menghitung gaya hambat air dan gaya angkat aerodinamika dari pesawat Wing In Surface Effect kapasitas 8 orang model 3 Dimensi dengan konfigurasi Berat Maksimum saat take off sebesar 32000 Newton pada kecepatan cruise 80 knots pada ketinggian terbang 2.5 meter. Aspek eksperimen pada uji model towing tank dan data uji terbang pada prototipe pesawat Wing In Surface Effect kapasitas (1-2) orang saat hydro planing dijelaskan dengan menggunakan teori gelombang hidrodinamika dan porpoising efek. [The Hump Drags During Hydro planing and Aerodynamic Lift During Cruise in Surface Effect Altitude Of Wing in Surface Effect Craft] The computational fluid dynamics of 3 Dimensions model of Wing in Surface Effect craft is very important to proof the model towing test and flight testing data. The inverse delta wing and shoulder airfoil is by using Clark Y of Lippisch configurations have been designed for the surface effect characteristics. The first Maxsurf software are used to compared the towing test results during hydro planing phase. The second ANSYS CFX software is used to calculate the hump drags and aerodynamic lift of Wing In Surface Effect craft 8 seaters 3 Dimensions model to verified the Design Requirement and Objectives. The forces equilibrium on the body axis during hydro planing are very important to fulfill the take off phase on the water surface. And, the aerodynamic lift for Maximum Take off Weight of 8 seaters configuration is 32000 Newton during cruise speed at 80 knots on the 2.5 meter altitude. The experimental aspects of towing tank test model and Wing In Surface Effect craft (1-2) seaters prototype during hydro planing test have been proposed by using the hydrodynamic wave and porpoising effect theory.

Experimental Study of the Effect of the Pontoon Dimensions on the Flow-Induced Motions (FIM) of a Semi-Submersible Platform With Four Square Columns

2020 ◽  
Author(s):  
Rodolfo T. Gonçalves ◽  
Hideyuki Suzuki ◽  
Matheus A. Marques ◽  
Leandro S. P. Silva ◽  
Chenling Tian ◽  
...  
Keyword(s):  
Experimental Study ◽  
Fatigue Life ◽  
Transverse Direction ◽  
Vertical Direction ◽  
Model Tests ◽  
Mooring Line ◽  
Towing Tank ◽  
Spacing Ratio ◽  
Floating System ◽  
Four Square

Abstract The Flow-Induced Motions (FIM) is an essential topic on multi-column platforms due to the effect on the mooring line fatigue life. Vortex-Induced Motions (VIM) or galloping behavior can be observed for an array of four columns with square sections. The presence of pontoons showed to be important for changing the flow around the array and promoting different amplitude behaviors of the motions in the transverse direction mainly. This article aims to understand the effect of the presence of four pontoons on the FIM of a semi-submersible platform (SS) with four square section columns. Model tests of a floating system supported elastically utilizing four springs were performed in a towing tank. Five different pontoon ratios were tested, namely P/L = 0, 0.25, 0.50, 0.75, and 1.00; where P is the pontoon height (the dimension in the vertical direction), and L is the length of the square column face. The draft condition was kept constant as H/L = 1.5; where H is the draft of the platform. The spacing ratio of the columns was S/L = 4; where S is the distance between column centers. Two incidence angles of the current were carried out, namely 0 and 45 degrees. The amplitudes in the transverse direction (direction perpendicular to the incidence current) decreased by increasing the pontoon ratio for 0 and 45-deg incidences. The pontoons positioned aligned to the flow significantly reduced the amplitudes in the transverse direction since the pontoon presence in this position modified the incident wake in the downstream columns. The pontoon presence needs to be well investigated to choose the best condition to avoid raising the FIM or mitigating the FIM.

scholarly journals Numerical and Experimental Study of Blockage Effect Correction Method in Towing Tank

2019 ◽  
Vol 33 (5) ◽  
pp. 522-536 ◽  
Author(s):  
Chun-yu Guo ◽  
Pei Xu ◽  
Chao Wang ◽  
Zi Kan
Keyword(s):  
Experimental Study ◽  
Correction Method ◽  
Towing Tank ◽  
Blockage Effect

Experimental Study of Plasma Flow Control on Highly Swept Delta Wing

AIAA Journal ◽  
2010 ◽  
Vol 48 (1) ◽  
pp. 249-252 ◽  
Author(s):  
P. F. Zhang ◽  
J. J. Wang ◽  
L. H. Feng ◽  
G. B. Wang
Keyword(s):  
Experimental Study ◽  
Flow Control ◽  
Plasma Flow ◽  
Delta Wing ◽  
Plasma Flow Control
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