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−	==1 Title, abstract and keywords==	+	==INTRODUCTION==
−	Your document should start with a concise and informative title. Titles are often used in information-retrieval systems. Avoid abbreviations and formulae where possible. Capitalize the first word of the title.	+	The Transformable Craft (T-Craft) is a novel ship concept of the US Office of Naval Research, operative in multiple modes. T-Craft can deploy in an unloaded condition from the intermediate support base to the seabase, and then be used as a high speed connector to the shore, transporting wheeled and tracked vehicles through the surf zone and onto the beach.
−	Provide a maximum of 6 keywords, and avoiding general and plural terms and multiple concepts (avoid, for example, 'and', 'of'). Be sparing with abbreviations: only abbreviations firmly established in the field should be used. These keywords will be used for indexing purposes.	+	T-Craft has been conceived as a Surface-Effect Ship (SES). A SES is a non-amphibious vehicle supported by an air cushion, with flexible seals at the bow and stern, and twin hulls, like a catamaran, at the sides. Due to the lack of air leakage at the craft sides, lift power can be reduced significantly compared with other type of Air-Cushion Vehicles (ACV). Also, it is possible to install conventional water propellers or waterjet propulsion, with rather smaller machinery space requirements compared to that for air propellers or fans used on ACVs. Furthermore, the SES can operate in modes of full displacement, partial air-cushion support, and full aircushion support.
−	An abstract is required for every document; it should succinctly summarize the reason for the work, the main findings, and the conclusions of the study. Abstract is often presented separately from the article, so it must be able to stand alone. For this reason, references and hyperlinks should be avoided. If references are essential, then cite the author(s) and year(s). Also, non-standard or uncommon abbreviations should be avoided, but if essential they must be defined at their first mention in the abstract itself.	+	Predicting the overall performance of a SES is of paramount importance to support the design phase, as the motion of the ship can be affected by the interaction between the air, the cushion, the ship structure, the seals, the sea waves and the sea bottom in the shallow water region. Different approaches with different types of complexity and accuracy have been taken to cope with this type of analyses.
−	==2 The main text==	+	<span id='_Ref325361953'></span>
		+	In the last decade, there have been extensive applications of Navier-Stokes models to naval hydrodynamics problems. For example, Oñate and García-Espinosa [<span id='cite-1'></span>[[#1|1]]] presented a stabilized FEM for fluid structure interaction with free surface. In [<span id='cite-2'></span>[[#2|2]]] Löhner et al. developed a FEM capable of tracking violent free surface flows interacting with objects. Also García-Espinosa et al. [<span id='cite-3'></span>[[#3|3]]] developed a new technique to track complex free surface shapes. More recently, in [<span id='cite-4'></span>[[#4|4]]], an application for the calculation of the flow about a SES in still water, using a commercial Volume of Fluid model, has been presented. While, in [<span id='cite-5'></span>[[#5|5]]], Mousaviraad et al. uses an URANS solver for evaluating the manoeuvring performance of a SES. While the outcome of the analyses is outstanding, the CPU-time reported in this paper, makes this model quite unaffordable for being used during design stages.
−	You can enter and format the text of this document by selecting the ‘Edit’ option in the menu at the top of this frame or next to the title of every section of the document. This will give access to the visual editor. Alternatively, you can edit the source of this document (Wiki markup format) by selecting the ‘Edit source’ option.	+	<span id='_Ref345086558'></span>
		+	Actually, it is a common consensus that solvers based on the Navier-Stokes equations are too expensive computationally speaking when it comes to simulate unsteady naval hydrodynamics problems. These sorts of problems can be more efficiently calculated using potential flow theory. This approach, jointly with the Stokes perturbation approximation, is widely used for analysis of seakeeping problems [<span id='cite-6'></span>[[#6|6]]]. In [<span id='cite-7'></span>[[#7|7]]], Connell et al., uses a boundary-element time-domain potential flow solver to calculate the multi-body seakeeping behaviour of a T-Craft SES and a LMSR in different scenarios. While, in [<span id='cite-8'></span>[[#8|8]]], the same computational solver is adapted to calculate the manoeuvre of a SES.
−	Most of the documents in Scipedia are written in English (write your manuscript in American or British English, but not a mixture of these). Anyhow, specific publications in other languages can be published in Scipedia. In any case, the documents published in other languages must have an abstract written in English.	+	<span id='_Ref346124508'></span>
		+	Despite the complexity of the above referred SES computational models, none of them takes into account the seal dynamics, or the effect of free surface-seal interaction. However, it is well known the relevance of this interaction in the unsteady dynamics of a SES [<span id='cite-9'></span>[[#9|9]]][<span id='cite-10'></span>[[#10|10]]]. The complexity of this phenomenon makes impossible to develop a theoretical background, and prompts many design parameters to be traditionally decided by empirical formulas [<span id='cite-_Ref346124508'></span>[[#_Ref346124508|9]]]. Actually, only limited theoretical and computational models have been developed to analyze seal dynamics [<span id='cite-11'></span>[[#11|11]]][<span id='cite-12'></span>[[#12|12]]][<span id='cite-13'></span>[[#13|13]]].
−	===2.1 Subsections===	+	This presentation shows an extension of the work presented by Serván-Camas and García-Espinosa [<span id='cite-_Ref345086558'></span>[[#_Ref345086558|6]]] in the development of an efficient seakeeping solver. In particular, it is focused in the recent work of the authors in the development of a computational model for the analysis of the complex and highly dynamic behavior of the seals in the interface between the air cushion, and the water of a T-Craft [<span id='cite-14'></span>[[#14|14]]]. The fluid solver developed for this purpose, uses a potential flow approach along with a stream-line integration of the free surface. While this approximation is much simpler than using RANS computations, significant outcomes can be obtained as well, allowing to significantly reducing computational time by 2 or 3 orders of magnitude even when computing on a regular desktop or laptop.
−	Divide your article into clearly defined and numbered sections. Subsections should be numbered 1.1, 1.2, etc. and then 1.1.1, 1.1.2, ... Use this numbering also for internal cross-referencing: do not just refer to 'the text'. Any subsection may be given a brief heading. Capitalize the first word of the headings.	+	The developed fluid-structure interaction solver is based, on one side, on an implicit iteration algorithm, using a TCP/IP sockets link, able to communicate pressure forces and displacements of the seals at memory level and, on the other side, on an innovative wetting and drying scheme able to predict the water action on the seals.
−	===2.2 General guidelines===	+	==PRESENTATION==
−	Some general guidelines that should be followed in your manuscripts are:	+	This presentation was held at the 52º Congreso de Ingeniería Naval e Industria Marítima on October 23-25th, 2013.
−	:* Avoid hyphenation at the end of a line.	+	[[File:Draft_García-Espinosa_863798721_6381_52CIN.gif|link=https://prezi.com/iptbp8n9yvj4]]
−	:*  Symbols denoting vectors and matrices should be indicated in bold type. Scalar variable names should normally be expressed using italics.	+	==ACKNOWLEDGEMETS==
−	:*  Use decimal points (not commas); use a space for thousands (10 000 and above).	+	This work relates to Department of the Navy Grant N62909-10-1-7053 issued by Office of Naval Research Global. The United States Government has a royalty-free license throughout the world in all copyrightable material contained herein.
−	:*  Follow internationally accepted rules and conventions. In particular use the international system of units (SI). If other quantities are mentioned, give their equivalent in SI.	+	==REFERENCES==
−	===2.3 Tables, figures, lists and equations===	+	<div id="1"></div>
		+	[[#cite-1|[1]]] E. Oñate, J. García-Espinosa, A finite element method for fluid-structure interaction with surface waves using a finite calculus formulation, Comp. Methods Appl. Mech. and Eng. 2001; 191: 635-660.
−	Please insert tables as editable text and not as images. Tables should be placed next to the relevant text in the article. Number tables consecutively in accordance with their appearance in the text (<span id='cite-_Ref382560620'></span>[[#_Ref382560620|table 1]], table 2, etc.) and place any table notes below the table body. Be sparing in the use of tables and ensure that the data presented in them do not duplicate results described elsewhere in the article.	+	<div id="2"></div>
		+	[[#cite-2|[2]]] R. Löhner, C. Yang, E. Oñate, On the simulation of flows with violent free surface motion and moving objects using unstructured meshes, Comp. Methods Appl. Mech. Engng. 2007; 53: 1315-1338.
−	<span id='_Ref382560620'></span>	+	<div id="3"></div>
−	{| style="margin: 1em auto 1em auto;border: 1pt solid black;border-collapse: collapse;"	+	[[#cite-3|[3]]] J. García-Espinosa, A. Valls, E. Oñate, ODDLS: A new unstructured mesh finite element method for the analysis of free surface flow problems, Int. J. Numer.  Meth.  Fluids 2008; 76 (9): 1297-1327.
−	|-	+
−	| style="text-align: center;"|Thickness	+
−	| style="text-align: center;"|3.175 mm	+
−	|-	+
−	| style="text-align: center;"|Young Modulus	+
−	| style="text-align: center;"|12.74 MPa	+
−	|-	+
−	| style="text-align: center;"|Poisson coefficient	+
−	| style="text-align: center;"|0.25	+
−	|-	+
−	| style="text-align: center;"|Density	+
−	| style="text-align: center;"|1107 kg/m<sup>3</sup>	+
−	|}	+
−	<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">	+
−	<span style="text-align: center; font-size: 75%;">Table 1: Material properties</span></div>	+
−	Graphics may be inserted directly in the document and positioned as they should appear in the final manuscript.	+	<div id="4"></div>
		+	[[#cite-4|[4]]] D. J. Donnelly, W. L. Neu, Numerical Simulation of Flow About a Surface-Effect Ship, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.
−	<span id='_Ref448852946'></span>	+	<div id="5"></div>
−	<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">	+	[[#cite-5|[5]]] S. M. Mousaviraad, S. Bhushan, F. Stern, CFD Prediction of Free-Running SES/ACV Deep and Shallow Water Maneuvering in Calm Water and Waves,  MARSIM 2012. Singapore, April 23-27, 2012.
−	[[Image:Scipedia.gif|center|480px]]	+
−	</div>	+
−	<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">	+
−	<span style="text-align: center; font-size: 75%;">Figure 1. Scipedia logo.</span></div>	+
−	Number the figures according to their sequence in the text (<span id='cite-_Ref448852946'></span>[[#_Ref448852946|figure 1]], figure 2, etc.). Ensure that each illustration has a caption. A caption should comprise a brief title. Keep text in the illustrations themselves to a minimum but explain all symbols and abbreviations used. Try to keep the resolution of the figures to a minimum of 300 dpi. If a finer resolution is required, the figure can be inserted as supplementary material	+	<div id="6"></div>
		+	[[#cite-6|[6]]] B. Serván-Camas, J. García-Espinosa, Accelerated 3D multi-body seakeeping simulations using unstructured finite elements, J. Comp. Phys. 252 (2013) 382–403.
−	For tabular summations that do not deserve to be presented as a table, lists are often used. Lists may be either numbered or bulleted. Below you see examples of both.	+	<div id="7"></div>
		+	[[#cite-7|[7]]] B. S. H. Connell, W. M. Milewski, B. Goldman, D. C. Kring, Single and Multi-Body Surface Effect Ship Simulation for T-Craft Design Evaluation, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.
−	1. The first entry in this list	+	<div id="8"></div>
		+	[[#cite-8|[8]]] D. C. Kring, M. K. Parish, W. M. Milewski, B. S. H. Connell, Simulation of Maneuvering in Waves for a High-Speed Surface Effect Ship, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.
−	2. The second entry	+	<div id="9"></div>
		+	[[#cite-9|[9]]] L. Yun, A. Bliault, Theory &Design of Air Cushion Craft, Elsevier 2005.
−	2.1. A subentry	+	<div id="10"></div>
		+	[[#cite-10|[10]]] N. Hirata, O. M. Faltinsen, Computation of Cobblestone effect with unsteady viscous flow under a stern seal bag of a SES, Journal of Fluids and Structures, 2000: 14, 1053–1069.
−	3. The last entry	+	<div id="11"></div>
		+	[[#cite-11|[11]]] L. J. Doctors, Nonlinear motion of an air-cushion vehicle over waves, Journal of Hydronautics 1975: 9 (2), 44–57.
−	* A bulleted list item	+	<div id="12"></div>
		+	[[#cite-12|[12]]] P. A. Sullivan, P. A. Charest, T. Ma, Heave stiffness of an air cushion vehicle bag and finger skirt, Journal of Ship Research 1994: 38 (4), 302–307.
−	* Another one	+	<div id="13"></div>
		+	[[#cite-13|[13]]] Q. Yang, V. Jones, L. McCue, Investigation of Skirt Dynamics of Air Cushion Vehicles under Non-linear Wave Impact Using a SPH-FEM Model, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawaii. September 2001.
−	You may choose to number equations for easy referencing. In that case they must be numbered consecutively with Arabic numerals in parentheses on the right hand side of the page. Below is an example of formulae that should be referenced as eq. <span id='cite-_Ref424030152'></span>[[#_Ref424030152|(1)]].	+	<div id="14"></div>
		+	[[#cite-14|[14]]] Evaluating Manoeuvering and Seakeeping Performance of a Surface Effect Ship, Technical Report, CIMNE IT-630, October 2012.
−	{| style="width: 100%;"	+	<div id="15"></div>
−	|-	+	[[#cite-15|[15]]] O. C. Zienkiewicz, R. L. Taylor, J. Z. Zhu, The Finite Element Method: Its Basis and Fundamentals, Butterworth–Heinemann, ISBN 0750663200, 2005.
−	| style="vertical-align: top;"| <math>{\nabla }^{2}\phi =0</math>	+
−	| style="text-align: right;"|<span id='_Ref424030152'></span>	+
−	(1)	+
−	|}	+
−	===2.4 Supplementary material===	+	<div id="16"></div>
		+	[[#cite-16|[16]]] S. R. Idelsohn, E. Oñate, C. Sacco, Finite element solution of free-surface ship-wave problems,  Int. J. Numer. Meth. Engng. 45, 50-528 (1999)
−	Supplementary material can be inserted to support and enhance your article. This includes video material, animation sequences, background datasets, computational models, sound clips and more. In order to ensure that your material is directly usable, please provide the files with a preferred maximum size of 50 MB. Please supply a concise and descriptive caption for each file.	+	<div id="17"></div>
		+	[[#cite-17|[17]]] R. L. Taylor, E. Oñate, P.-A. Ubach, Finite element analysis of membrane structures, Textile composites and inflatable structures. Springer (2005) 47-68.
−	==3 Bibliography==	+	<div id="18"></div>
		+	[[#cite-18|[18]]] C. Felippa, B. Haugen, A unified formulation of small-strain corotational finite elements: I. Theory, Computer Methods in Applied Mechanics and Engineering 194 (2005) 2285–2335
−	<span id='_Ref449344604'></span>	+	<div id="19"></div>
−	Citations in text will follow a citation-sequence system (i.e. sources are numbered by order of reference so that the first reference cited in the document is [<span id='cite-1'></span>[[#1|1]]], the second [<span id='cite-2'></span>[[#2|2]]], and so on) with the number of the reference in square brackets. Once a source has been cited, the same number is used in all subsequent references. If the numbers are not in a continuous sequence, use commas (with no spaces) between numbers. If you have more than two numbers in a continuous sequence, use the first and last number of the sequence joined by a hyphen (e.g. [<span id='cite-1'></span>[[#1|1]], <span id='cite-3'></span>[[#3|3]]] or [<span id='cite-2'></span>[[#2|2]]-<span id='cite-2'></span>[[#4|4]]]).	+	[[#cite-19|[19]]] C. A. Felippa, C. Militello, Membrane triangles with corner drilling freedoms: II. The ANDES element, Finite Elem Anal Des, (1992) 12:189–201.
−	<span id='_Ref449084254'></span>	+	<div id="20"></div>
−	You should ensure that all references are cited in the text and that the reference list. References should preferably refer to documents published in Scipedia. Unpublished results should not be included in the reference list, but can be mentioned in the text. The reference data must be updated once publication is ready. Complete bibliographic information for all cited references must be given following the standards in the field (IEEE and ISO 690 standards are recommended). If possible, a hyperlink to the referenced publication should be given. See examples for Scipedia’s articles [<span id='cite-1'></span>[[#1|1]]], other publication articles [<span id='cite-2'></span>[[#2|2]]], books [<span id='cite-3'></span>[[#3|3]]], book chapter [<span id='cite-4'></span>[[#4|4]]], conference proceedings [<span id='cite-5'></span>[[#5|5]]], and online documents [<span id='cite-6'></span>[[#6|6]]], shown in references section below.	+	[[#cite-20|[20]]] M. A. Crisfield, Non-linear Finite Element Analysis of Solid and Structures, Advanced Topics, vol. 2, Wiley, 1997.
−	==4 Acknowledgments==	+	<div id="21"></div>
		+	[[#cite-21|[21]]] F. S. Almeida, A. M. Awruch, Corotational nonlinear dynamic analysis of laminated composite shells, Finite Elements in Analysis and Design 47 (2011) 1131–1145.
−	Acknowledgments should be inserted at the end of the document, before the references section.	+	<div id="22"></div>
		+	[[#cite-22|[22]]] A. Ibrahimbegovic, S. Mamouri, Energy conserving/decaying implicit time-stepping scheme for nonlinear dynamics of three-dimensional beams undergoing finite rotations, Computer Methods in Applied Mechanics and Engineering 191 (2002) 4241–4258.
−	==5 References==	+	<div id="23"></div>
		+	[[#cite-23|[23]]] C. A. Felippa, K. C. Park, C. Farhat, “Partitioned analysis of coupled mechanical systems,” Comput. Methods Appl. Mech. Eng., vol. 190, pp. 3247–3270, 2001.
−	<span id='_Ref449083719'></span>	+	<div id="24"></div>
−	<div id="1"></div>	+	[[#cite-24|[24]]] J. G. Valdés, “Nonlinear analysis of orthotropic membrane and shell structures including fluid-structure interaction,” PhD thesis, Barcelona Tech., 2007.
−	[[#cite-1|[1]]] Author, A. and Author, B. (Year) Title of the article. Title of the Publication. Article code. Available: [http://www.scipedia.com/ucode. http://www.scipedia.com/ucode.]	+
−	<div id="2"></div>	+	<div id="25"></div>
−	[[#cite-2|[2]]] Author, A. and Author, B. (Year) Title of the article. Title of the Publication. Volume number, first page-last page.	+	[[#cite-25|[25]]] B. M. Irons, R. C. Tuck, “A Version of the Aitken Accelerator for Computer Iteration,” Int. J. Numer. Methods Eng., vol. 1, pp. 275–277, 1969.
−	<div id="3"></div>	+	<div id="26"></div>
−	[[#cite-3|[3]]] Author, C. (Year). Title of work: Subtitle (edition.). Volume(s). Place of publication: Publisher.	+	[[#cite-26|[26]]] S. F. Zalek , L. J. Doctors, Experimental Study of the Resistance of Surface-Effect-Ship Seals, Proceeding of the 28th Symposium on Naval Hydrodynamics, 2010.
−	<div id="4"></div>	+	<div id="27"></div>
−	[[#cite-4|[4]]] Author of Part, D. (Year). Title of chapter or part. In A. Editor & B. Editor (Eds.), Title: Subtitle of book (edition, inclusive page numbers). Place of publication: Publisher.	+	[[#cite-27|[27]]] R. J. Paredes, Smoothed particle hydrodynamics applied to fluid structure interaction problems involving hydroelastic response, Ph.D. thesis, Stevens Institute of Technology, United States of America, 2013.
−	<div id="5"></div>	+	<div id="28"></div>
−	[[#cite-5|[5]]] Author, E. (Year, Month date). Title of the article. In A. Editor, B. Editor, and C. Editor. Title of published proceedings. Paper presented at title of conference, Volume number, first page-last page. Place of publication.	+	[[#cite-28|[28]]] A. D. Wiggins, S. F. Zalek, M. Perlin, S. L. Ceccio, Development of large scale surface effect ship bow seal testing plataform. 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.
−	<div id="6"></div>	+	<div id="29"></div>
−	[[#cite-6|[6]]] Institution or author. Title of the document. Year. [Online] (Date consulted: day, month and year). Available: [http://www.scipedia.com/document.pdf http://www.scipedia.com/document.pdf]. [Accessed day, month and year].	+	[[#cite-29|[29]]] J. García-Espinosa, B. Servan Camas, E. ONATE, D. Capua and P. Ubach de Fuentes, A FEM fluid-structure interaction algorithm for analysis of the seal dynamics of a Surface-Effect Ship, Comp. Meth. App. Mech. Eng., vol 295, pp. 290–304, Oct. 2015. DOI 10.1016/j.cma.2015.07.010. URL https://www.scipedia.com/public/García-Espinosa_2016a.

---

Latest revision as of 19:13, 14 January 2021

INTRODUCTION

The Transformable Craft (T-Craft) is a novel ship concept of the US Office of Naval Research, operative in multiple modes. T-Craft can deploy in an unloaded condition from the intermediate support base to the seabase, and then be used as a high speed connector to the shore, transporting wheeled and tracked vehicles through the surf zone and onto the beach.

T-Craft has been conceived as a Surface-Effect Ship (SES). A SES is a non-amphibious vehicle supported by an air cushion, with flexible seals at the bow and stern, and twin hulls, like a catamaran, at the sides. Due to the lack of air leakage at the craft sides, lift power can be reduced significantly compared with other type of Air-Cushion Vehicles (ACV). Also, it is possible to install conventional water propellers or waterjet propulsion, with rather smaller machinery space requirements compared to that for air propellers or fans used on ACVs. Furthermore, the SES can operate in modes of full displacement, partial air-cushion support, and full aircushion support.

Predicting the overall performance of a SES is of paramount importance to support the design phase, as the motion of the ship can be affected by the interaction between the air, the cushion, the ship structure, the seals, the sea waves and the sea bottom in the shallow water region. Different approaches with different types of complexity and accuracy have been taken to cope with this type of analyses.

In the last decade, there have been extensive applications of Navier-Stokes models to naval hydrodynamics problems. For example, Oñate and García-Espinosa [1] presented a stabilized FEM for fluid structure interaction with free surface. In [2] Löhner et al. developed a FEM capable of tracking violent free surface flows interacting with objects. Also García-Espinosa et al. [3] developed a new technique to track complex free surface shapes. More recently, in [4], an application for the calculation of the flow about a SES in still water, using a commercial Volume of Fluid model, has been presented. While, in [5], Mousaviraad et al. uses an URANS solver for evaluating the manoeuvring performance of a SES. While the outcome of the analyses is outstanding, the CPU-time reported in this paper, makes this model quite unaffordable for being used during design stages.

Actually, it is a common consensus that solvers based on the Navier-Stokes equations are too expensive computationally speaking when it comes to simulate unsteady naval hydrodynamics problems. These sorts of problems can be more efficiently calculated using potential flow theory. This approach, jointly with the Stokes perturbation approximation, is widely used for analysis of seakeeping problems [6]. In [7], Connell et al., uses a boundary-element time-domain potential flow solver to calculate the multi-body seakeeping behaviour of a T-Craft SES and a LMSR in different scenarios. While, in [8], the same computational solver is adapted to calculate the manoeuvre of a SES.

Despite the complexity of the above referred SES computational models, none of them takes into account the seal dynamics, or the effect of free surface-seal interaction. However, it is well known the relevance of this interaction in the unsteady dynamics of a SES [9][10]. The complexity of this phenomenon makes impossible to develop a theoretical background, and prompts many design parameters to be traditionally decided by empirical formulas [9]. Actually, only limited theoretical and computational models have been developed to analyze seal dynamics [11][12][13].

This presentation shows an extension of the work presented by Serván-Camas and García-Espinosa [6] in the development of an efficient seakeeping solver. In particular, it is focused in the recent work of the authors in the development of a computational model for the analysis of the complex and highly dynamic behavior of the seals in the interface between the air cushion, and the water of a T-Craft [14]. The fluid solver developed for this purpose, uses a potential flow approach along with a stream-line integration of the free surface. While this approximation is much simpler than using RANS computations, significant outcomes can be obtained as well, allowing to significantly reducing computational time by 2 or 3 orders of magnitude even when computing on a regular desktop or laptop.

The developed fluid-structure interaction solver is based, on one side, on an implicit iteration algorithm, using a TCP/IP sockets link, able to communicate pressure forces and displacements of the seals at memory level and, on the other side, on an innovative wetting and drying scheme able to predict the water action on the seals.

PRESENTATION

This presentation was held at the 52º Congreso de Ingeniería Naval e Industria Marítima on October 23-25th, 2013.

ACKNOWLEDGEMETS

This work relates to Department of the Navy Grant N62909-10-1-7053 issued by Office of Naval Research Global. The United States Government has a royalty-free license throughout the world in all copyrightable material contained herein.

REFERENCES

[1] E. Oñate, J. García-Espinosa, A finite element method for fluid-structure interaction with surface waves using a finite calculus formulation, Comp. Methods Appl. Mech. and Eng. 2001; 191: 635-660.

[2] R. Löhner, C. Yang, E. Oñate, On the simulation of flows with violent free surface motion and moving objects using unstructured meshes, Comp. Methods Appl. Mech. Engng. 2007; 53: 1315-1338.

[3] J. García-Espinosa, A. Valls, E. Oñate, ODDLS: A new unstructured mesh finite element method for the analysis of free surface flow problems, Int. J. Numer.  Meth.  Fluids 2008; 76 (9): 1297-1327.

[4] D. J. Donnelly, W. L. Neu, Numerical Simulation of Flow About a Surface-Effect Ship, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.

[5] S. M. Mousaviraad, S. Bhushan, F. Stern, CFD Prediction of Free-Running SES/ACV Deep and Shallow Water Maneuvering in Calm Water and Waves, MARSIM 2012. Singapore, April 23-27, 2012.

[6] B. Serván-Camas, J. García-Espinosa, Accelerated 3D multi-body seakeeping simulations using unstructured finite elements, J. Comp. Phys. 252 (2013) 382–403.

[7] B. S. H. Connell, W. M. Milewski, B. Goldman, D. C. Kring, Single and Multi-Body Surface Effect Ship Simulation for T-Craft Design Evaluation, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.

[8] D. C. Kring, M. K. Parish, W. M. Milewski, B. S. H. Connell, Simulation of Maneuvering in Waves for a High-Speed Surface Effect Ship, 11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawai. September 2001.

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