Hull Performance Assessment and Comparison of Ship-Shaped and Cylindrical FPSOs With Regards To: Stability, Sea-Keeping, Mooring and Riser Loads In Shallow Water 2 2 Floating, Production, Storage and Offloading “FPSO” have become a popular choice since 1980s for marginal and fast-track developments where subsea pipeline is not an economic or feasible solution for export. Field development usually starts with a concept selection procedure which is constituted from a sequence of multi-disciplinary decision making tasks. As limited data is available in the early phase of the development, operators require a robust and rational decision making process to reduce the drawback of immature information. The Multi-Criteria Decision Making (MCDM) process which is used in this paper is an industrial approved and accepted decision making process that can resolve this requirement. This method is commonly used as a decision making method for multiple attributes problems. The main objective of this study is to illustrate the application of this method for concept selection for shallow water fields. Here the problem is reduced to a selection among two common FPSO concepts: ship-shaped and cylindrical by assessing their performances for the same location. The primary attributes which have been used for performance assessment includes: stability, motions and accelerations, riser stresses and mooring line tensions under both intact and damaged conditions. To simplify the problem, the same topside weight and tank capacity are considered and response comparison is limited to the linear responses induced by wave under full loaded conditions. For both FPSOs spread mooring system with steep-s flexible riser system are considered. For the given environmental conditions, cylindrical FPSO shows better motion characteristics which leads to smaller mooring and riser loads. This method should be generalized for other shallow water production system by including all the attributes used in the shallow water field development concept selection 1 13 2017/05/6 1396/2/16 2017/11/25 1396/9/4 Navid Baghernezhad Navid Baghernezhad Faculty of marine engineering, Petroleum University of Technology iran N.Baghernejad@put.ac.ir Pedram Edalat Pedram Edalat Faculty of marine engineering, Petroleum University of Technology iran Edalat@put.ac.ir Mahmoud Etemaddar Mahmoud Etemaddar Center of ships and offshore structures, Trondheim, NORWAY NORWAY Mahmoud.Etemaddar@gmail.com FPSO concept design Multidisciplinary system Stability Seakeeping Mooring and riser Persian Gulf D’Souza, R., (1994), An approach to the design and selection of a cost effective floating production storage and offloading system, Offshore Technology Conference (OTC 7443), Houston.##PAIK, J. and THAYAMBALLI, K., (2007), Ship-Shaped Offshore Installations, design, building and operation, Cambridge University Press, New York.##Terpstra, T. and MacMillan, A., (2001), FPSO design and conversion: A designer's approach, Offshore Technology Conference (OTC), Houston.##Ruyter, W., (2005), The Sanha LPG FPSO, Offshore Technology Conference (OTC), Houston.##Yukawa, K., Kato, S. and Hayashi, T., (2015), Study on the design requirements of external turret mooring for FLNG, Journal of the japan society of naval architects and ocean engineerings, Vol.22, p.83-94.##Anundsen, T., (2008), Operability comparison of three ultra-deepwater and harsh environment drilling vessels, Master thesis, Stavanger University.##Ogbonnaya, E.A., (2012), Hull design requirements of floating production, storage and offloading, International Journal of Engineering and Innovative Technology (IJEIT), Vol.2, Issue.6 n, ISSN: 2277-3754.##Babadi, M.K., and Ghassemi, H., (2013), Effect of hull form coefficients on the vessel sea-keeping performance, Journal of Marine Science and Technology, Vol.21, p.594-604.##Sario¨z, K., and Narli, E., (2004), Effect of criteria on seakeeping performance assessment, Ocean Engineering journal, Vol.32, p.1161–1173##Ukooa FPSO Design Guidance Notes for UKCS Service, (2002), Offshore LTD., Project Reviews LTD.##Fernández, R.P., (2012), Seakeeping in the navigation – Example in trimaran ships, International Journal for Traffic and Transport Engineering, Vol.3, p.221 – 235.##Siow, C.L., Koto, J., and Yasukawa, H., (2015), Wave Induce Motion of Round Shaped FPSO, Journal of Subsea and Offshore, Vol.1, p.9-17.##Cepowski, T., (2010), The modeling of seakeeping qualities of floating, production, storage and offloading (FPSO) sea-going ships in preliminary design stage, POLISH MARITIME RESEARCH, Vol. 17, p.3-12.##Kumar, D., (2010), Selection of mooring system for FPSO in shallow water, Petrotech, New Delhi.##Huang, K., (2000), Mooring system design consideration for FPSOs, International offshore and polar engineering conference, Houston.##ISO19901-7, (2013), Petroleum and natural gas industries, Specific requirements for offshore, Station keeping systems for floating, Second edition.##Baghernezhad, N., Edalat, P., and Etemaddar, M., (2016), Stability and seakeeping performance assessment of a ship shape FPSO in three main operational conditions at Persian Gulf: full loaded; half loaded and full ballast", The 18th Marine Industries Conference (MIC2016), Kish Island.##Triantaphyllou, E., (1998), Multi-Criteria Decision Making: An operations research approach Encyclopedia of Electrical and Electronics Engineering, Vol.15, p.175-186.##Velasquez, M. and Hester, P.T., (2013), An Analysis of Multi-Criteria Decision Making Methods, International Journal of Operations Research, Vol.10, p.56-66.##Brown, Alan., Thomas, M., (1998), Reengineering the naval ship concept design process, Research to Reality in Ship Systems Engineering Symposium, ASNE.##IMO, (2008), IMO IS CODE, PART B, CHAPTER 2.4.5.##MARPOL, (1994), MARPOL, REGULATION 25.3C.##DNV-OS-C301, (2013), Stability and Watertight Integrity, Offshore standard.##API, (2013), Design and analysis of station keeping systems for floating structures, Third edition.##ISO8041, (1999), Human response to vibration-measuring instrumentation.##ISO2631-1, (1997), Mechanical vibration and shock-evaluation of human exposure to whole-body vibration.##Willson, J., (2003), Dynamics of offshore structures, Canada.##DNV-RP-C205, (2010), ENVIRONMENTAL CONDITIONS AND ENVIRONMENTAL LOADS.##Saidee, M.H., (2015), Fatigue Analysis and Design of Mooring Systems Assessment and comparison of different methods, Master thesis, Norwegian University of Science and Technology, Trondheim##DNV-OS-E301, (2013), Position Mooring, offshore standard##DNV-OS-E302, (2008), Offshore mooring chain, OFFSHORE STANDARD DET NORSKE VERITAS##DNV-OSS-302, (2003), Offshore riser systems, Offshore service specification, DET NORSKE VERITAS##DNV-OS-F201, (2010), Dynamic risers, Offshore standard, DET NORSKE VERITAS## ##

Numerical Evaluation of Cushioning Pressure in Water Entry of Rigid Bodies 2 2 Effect of air cushion layer right before impact of a rigid body onto water surface has been investigated in this paper. The study is mainly focused on evaluation of cushioning pressure and the resulting free surface elevation. The air flow is assumed to be an irrotational flow which is governed by Laplace equation. The air problem and the resulting response of the water free surface are supposed to be weakly coupled because of very low air pressure. Integral equation for each medium has been numerically solved separately using boundary element method. The problem is assumed to be unsteady with a constant body speed. The numerical results have been also compared with analytical method which shows a fair agreement. Results show that the geometry of impacting body and particularly its bluntness are the primary affecting parameter which can dramatically influence the free surface profile and air pressure. Such a behavior has been observed for two different geometries, ellipse and wedge section, having identical breadth. 15 24 2017/05/62017/03/11 1395/12/21 2017/11/252017/11/25 1396/9/4 Mojtaba Barjasteh Mojtaba Barjasteh Faculty of maritime engineering iran barjasteh@aut.ac.ir Hamid Zeraatgar Hamid Zeraatgar Faculty of maritime engineering iran hamidz@aut.ac.ir Water entry Air cushion Cushioning effect Verhagen, J.H.G., (1967), The impact of a flat plate on a water surface, Ship Res., Vol. 11, p.211-233.##Wilson, S.K., (1991), A mathematical model for the initial stages of fluid impact in the presence of a cushioning fluid layer, Engineering Mathematics, Vol. 25, p. 265-285##Hicks, P.D., Ermanyuk, E.V., Gavrilov, N.V. and Purvis, R., (2012), Air trapping at impact of a rigid sphere onto a liquid, Fluid Mechanics, Vol. 695, p. 310-320.##Hicks, P. and Purvis, R., (2011), Air cushioning in droplet impacts with liquid layers and other droplets, physics of fluids, 23(6).##Tran, T., de Maleprade, H., Sun, C. and Lohse, D., (2013), Air entrainment during impact of droplets on liquid surfaces, Fluid Mechanics, Vol. 726.##Worthington, A.M., (1908), A Study of Splashes, Longmans, Green.##Thoroddsen, S.T., Etoh, T.G., Takehara, K., Ootsuka, N. and Hatsuki, Y., (2005), The air bubble entrapped under a drop impacting on a solid surface, Fluid Mechanics, Vol. 545, p. 203-212.##Marston, J.O., VAKARELSKI, I.U., THORODDSEN, S.T., (2011), Bubble entrapment during sphere impact onto quiescent liquid surfaces, Fluid Mechanics, Vol. 680, p.660-670.##Von Karman, T., (1929), The impact on seaplane floats during landing, N.A.C.A.T.N. No. 321.##Wagner, H., (1931), Phenomena associated with impact and sliding on liquid surfaces, N.A.C.A. Translation 1366.##Chuang, S.L., (1970), Investigation of Impact of Rigid and Elastic Bodies with Water, Management Information Services.##Nethercote, W.C.E., Mackay, M. and Menon, B., (1986), Some warship slamming investigations, D.R.E.A. Technical Memorandum 86/206.##Okada, S. and Sumi, Y., (2000), On the water impact and elastic response of a flat plate at small impact angles, Journal of Marine Science and Technology, Vol.5, p. 31-39.##Ermanyuk, E.V. and Ohkusu, M., (2005), Impact of a disk on shallow water, Fluids and Structures, Vol.20, p. 345-357.##Huera-Huarte, F.J., Jeon, D. and Gharib, M., (2011), Experimental investigation of water slamming loads on panels, Ocean Engineering, Vol.38, p. 1347-1355.##Lewison, G.R.G. and Maclean, W.M., (1968), On the cushioning of water impact by entrapped air, Ship Res., Vo.12, p.116-130.##Lewison, G.R.G., (1970), On the reduction of slamming pressures, Trans. R.I.N.A., Vol. 112, p. 285-306.##Asryan, N.G., (1972), Solid plate impact on surface of incompressible fluid in the presence of a gas layer between them, Izv. Akad. Nauk Arm. SSR Mekh, Vol. 25, p. 32-49.##Hicks, P. and Purvis, R., (2010), Air cushioning and bubble entrapment in three-dimensional droplet impacts, Fluid Mechanics, Vol. 649, p.135-163.##Bouwhuis, W., van der Veen, R.C.A., Tran, T., Keij, D. L., Winkels, K.G., Peters, I.R., van der Meer, D., Sun, C., Snoeijer, J.H. and Lohse, D., (2012), Maximal Air Bubble Entrainment at Liquid-Drop Impact, PHYSICAL REVIEW LET TE RS, PRL 109, 264501##Yousefnezhad, R. and Zeraatgar, H., (2014), A parametric study on water-entry of a twin wedge by boundary element method, J Mar Sci Technol, vol. 19, p. 314-326.##Katsikadelis, J.T., (2002), BOUNDARY ELEMENTS: Theory and Applications, Elsevier.## ##

Investigation of Drag Coefficient at Subcritical and Critical Reynolds Number Region for Circular Cylinder with Helical Grooves 2 2 Drag reduction of an object is the major concern in many engineering applications. Experimental studies have been carried out on circular cylinder with helical grooves in a subsonic wind tunnel. Different cases of helical grooves with different pitches, helical groove angles and number of starts of helical groove on circular cylinder are tested. Experimental results show the drag coefficient is sensitive with Reynolds number and decreases at critical Reynolds number and at subcritical and supercritical or transcritical Reynolds number the drag coefficient increases as compared with smooth cylinder. The longitudinal grooves over the cylinder surface are tested and showed that drag coefficient much decreases at the subcritical and critical Reynolds number region. The experimental results are validated with available literature and obtained good agreement. 25 33 2017/05/62017/03/112017/07/1 1396/4/10 2017/11/252017/11/252017/11/25 1396/9/4 Dewan Hasan Ahmed Dewan Hasan Ahmed Mechanical and Production Engineering Department, Ahsanullah University of Science and Technology, Bangladesh Bangladesh dhahmed@hotmail.com Md. Ashraful Haque Md. Ashraful Haque Mechanical and Production Engineering Department, Ahsanullah University of Science and Technology, Bangladesh Bangladesh rabbi.asia@gmail.com Md, Abdur Rauf Md, Abdur Rauf Mechanical and Production Engineering Department, Ahsanullah University of Science and Technology, Bangladesh Bangladesh arauf8621de@hotmail.com Helical groove circular cylinder drag coefficient subcritical Reynolds number critical Reynolds number drag force Sakamoto, H., Tan, K. and Haniu, H., (1991), An Optimum Suppression of Fluid Forces by Controlling a Shear Layer Separated From a Square Prism, Journal of Fluids Engineering, Vol.113(2), p.183-189.##Fujisawa, N. and Takeda, G., (2003), Flow control around a circular cylinder by internal acoustic excitation, Journal of Fluids and Structures, Vol.17(7), p.903–913.##Igarashi, T. and Tsutsui, T., (1989), Flow Control Around a Circular Cylinder by a New Method : 2nd Report, Fluid Forces Acting on the Cylinder, Transactions of the Japan Society of Mechanical Engineers Series B, Vol.55(511), p.708-714.##Igarashi, T. and Tsutsui, T., (1991), Flow Control around a Circular Cylinder by a New Method : 3rd Report, Properties of the Reattachment Jet, Transactions of the Japan Society of Mechanical Engineers Series B, Vol.57(533), p.8-13.##Raayai-Ardakani, S. and McKinley, GH., (2017), Drag reduction using wrinkled surfaces in high Reynolds number laminar boundary layer flows, Physics of Fluids, Vol.29(093605), p.093605-1-16.##Matsumoto, H., Kubota, Y., Ohishi, M., and Mochizuki, O., (2016), Drag on a Cylinder with an Apple-Shaped Cross Section, World Journal of Mechanics, Vol.6, p.323-339.##Yunqing, G., Tao, L., Jiegang, M., Zhengzan, S., and Peijian, Z., (2017), Analysis of Drag Reduction Methods and Mechanisms of Turbulent, Applied Bionics and Biomechanics, Article ID 6858720, 8 pages.##Zdravkovich, MM., (1977), Review of Flow Interference Between Two Circular Cylinders in Various Arrangements, Journal of Fluids Engineering, Vol.99(4), p.618-633.##Sakamoto, H. and Haniu, H., (1994), Optimum Suppression of Fluid Forces Acting on a Circular Cylinder, Journal of Fluids Engineering, Vol.116(2), p.221-227.##Bai, Q., Bai, J., Meng, X., Ji, C., and Liang, Y., (2016), Drag reduction characteristics and flow field analysis of textured Surface, Friction, Vol.4(2), p.165–175.##Coustols, E., (2001), Effect of grooved surfaces on the structure of a turbulent boundary layer, Mec. Ind 2.421-234. Edition scientifique et médicale Elsevier SAS. S1296-2139(01)01125-3/FLA.##Talley, S. and Mungal, G., (2002), Flow around cactus-shaped cylinders, Center for Turbulence Research Annual Research Briefs, p.363-376.##Yokoi, Y., Igarashi, T. and Hirao, K., (2011), The Study about Drag Reduction of a Circular Cylinder with Grooves, Journal of Fluid Science and Technology, 6(4), p.637.##Yamagishi, Y. and Oki, M., (2004), Effect of Groove Shape on Flow Characteristics around a Circular Cylinder with Grooves, Journal of Visualization, Vol.7(3), p.209-216.##Takayama, S. and Aoki, K., (2005), Flow Characteristics around a Rotating Grooved Circular Cylinder with Grooved of Different Depths, Journal of Visualization, Vol.8(4), p.295-303.##Dey, P. and Das, AK., (2015), Numerical analysis of drag and lift reduction of square cylinder, Engineering Science and Technology, an International Journal, Vol.18(4), p.758–768.##Ranjith, ER., Sunil, AS. and Pauly, L., (2016), Analysis of flow over a circular cylinder fitted with helical strakes, International Conference on Emerging Trends in Engineering, Science and Technology (ICETEST-2015), Procedia Technology 24, p.452 – 460.##Quen, LK., Abu, A., Kato, N., Muhamad, P., Sahekhaini, A. and Abdullah, H., (2014), Investigation on the effectiveness of helical strakes in suppressing VIV of flexible riser, Applied Ocean Research, 44, p.82–91.##Huang, S., (2011), VIV suppression of a two-degree-of-freedom circular cylinder and drag reduction of a fixed circular cylinder by the use of helical grooves, Journal of Fluids and Structures, 27, p.1124–1133.##Fage, A. and Warsap, JH., (1930), ARC R&M1283, (also §191, Modern Developments in Fluid Dynamics. 1965, ed.S. Goldstein).##Achenbach, E., (1971), Influence of surface roughness on the cross-flow around a cylinder, Journal of Fluid Mechanics, Vol.46(2), p.321-335.##Adachi, T., (1995), The Effect of Surface Roughness of a Body in the High Reynolds Number Flow, International Journal of Rotating Machinery, Vol.1(3-4), p.187-197##Hojo, T., (2015), Control of flow around a circular cylinder using a patterned surface, Computational Methods and Experimental Measurements XVII, WIT Transactions on Modelling and Simulation, Vol.59, p.245-256.##Rodríguez, I., Lehmkuhl, O., Chiva, J., Borrell, R. and Oliva, A., (2015), On the flow past a circular cylinder from critical to super-critical Reynolds numbers: Wake topology and vortex shedding, International Journal of Heat and Fluid Flow, Vol.55, p.91–103.##Cengel, YA. and Cimbala, JM., Fluid Mechanics Fundamentals and Applications. McGraw Hill Publishers.##Kimura, T. and Tsutahara, M., (1991), Fluid dynamic effects of grooves on circular cylinder surface, AIAA Journal, Vol.29 (12), p.2062-2068.##Sumer, BM. and Fredose, J., (1997), Hydrodynamics around circular cylinder, Vol.12, World Scientific publishing Co. Pte. Ltd.##Alonzo-García,A., Gutiérrez-Torres, C.del C. and Jiménez-Bernal, JA., (2014), Large Eddy Simulation of the Subcritical Flow over a U-Grooved Circular Cylinder, Advances in Mechanical Engineering, Vol.2014, Article ID 418398, 14 pages##Nakamura, Y. and Tomonari, Y., (1982), The effects of surface roughness on the flow past circular cylinders at high Reynolds numbers, Journal of Fluid Mechanics, Vol.123, p.363–378.##Ko, N.W.M., Leung, YC. and Chen, JJJ., (1987), Flow past V-groove circular cylinders, AIAA journal, Vol.25(6), p.806–811.##Zhou, B., Wang, X., Guo, W., Zheng, J., Tan, SK., (2015), Experimental measurements of the drag force and the near-wake flow patterns of a longitudinally grooved cylinder, Journal of Wind Engineering and Industrial Aerodynamics## ##

A New Propulsion System for Microswimmer Robot and Optimizing Geometrical Parameters Using PSO Algorithm 2 2 Mini and micro robots, which can swim in an underwater environment, have drawn widespread research interests because of their potential applications to the clinical drug delivery, biotechnology, manufacturing, mobile sensor networks, etc. In this paper, a prototype of microrobot based on the motion principle of living microorganisms such as E. Coli Bacteria is presented. The properties of this propulsive mechanism are estimated by modeling the dynamics of the swimming methods. For dynamic modeling and analysis of a tiny microrobot, which composed of a spherical head and four helix tail, the resistance force theory (RFT) is used to calculate thrust force, required torque, linear and angular velocities and then these physical and geometrical parameters are used to optimize the microrobot. In addition, a novel design method for determining the optimal geometrical parameters of dynamic system using the particle swarm optimization (PSO) reinforcement evolutionary algorithm is presented. Finally, the dynamical behavior of the optimized microrobot are simulated and the results are presented. 35 45 2017/05/62017/03/112017/07/12016/12/26 1395/10/6 2017/11/252017/11/252017/11/252017/11/25 1396/9/4 Hassan Sayyaadi Hassan Sayyaadi Sharif University of Technology iran sayyaadi@sharif.edu Abolfazl Motekallem Abolfazl Motekallem Sharif University of Technology iran motekallem_abolfazl@mech.sharif.ir Biomimetic Microrobot Swimming Robots Particle Swarm Optimization (PSO) Interventional Therapy Drug Delivery Abbott, J.J., Nagy, Z., Beyeler, F. and Nelson, B.J., (2007), Robotics in the small, part I: Microbotics, Robotics & Automation Magazine, IEEE, 14(2), p.92-103.##Abbott, J.J., Peyer, K.E., Lagomarsino, M.C., Zhang, L., Dong, L., Kaliakatsos, I.K. and Nelson, B.J., (2009), How should microrobots swim? The International Journal of Robotics Research, 28(11-12), p.1434-1447.##Nelson, B.J., Kaliakatsos, I.K. and Abbott, J.J., (2010), Microrobots for minimally invasive medicine, Annual Review of Biomedical Engineering, 12(1), p.55-85.##Purcell, E.M., (1977), Life at low Reynolds number, American Journal of Physics, 45(1), p.3-11.##Tottori, S., Zhang, L., Qiu, F., Krawczyk, K.K., Franco Obregon, A. and Nelson, B.J., (2012), Magnetic helical micro machines: Fabrication, controlled swimming and cargo transport, Advanced Materials, 24(6), p.811-816.##Zhang, L., Abbott, J.J., Dong, L., Kratochvil, B.E., Bell, D. and Nelson, B.J, (2009), Artificial bacterial flagella: Fabrication and magnetic control. Applied Physics Letters, 94(6), p. 064107-3##Fukuda, T., Kawamoto, A., Arai, F. and Matsuura, H., (1994), Mechanism and Swimming Experiment of Micro Mobile Robot in Water, Proc. of IEEE International Workshop on Micro Electro Mechanical Systems (MEMS’94), IEEE, New York, p. 273–278.##Guo, S., Hasegaw, Y., Fukuda, T. and Asaka, K., (2001), Fish Like Underwater Microrobot with Multi DOF, Proceedings of 200 International Symposium on Micro mechatronics and Human Science, IEEE, Nahoya, Japan, p. 63–68.##Jung, J., Kim, B., Tak, Y. and Park, J., (2003), Undulatory Tadpole Robot (Tad Rob) Using Ionic Polymer Metal Composite IMPC Actuator, Proceedings of 2003 IEEE International Conference on Intelligent Robots and Systems, IEEE, New York, p. 2133–2138.##10- Zhang, Y., Wang, Q., Zhang, P., Wang, X. and Mei, T., (2004), Dynamic Analysis and Experiment of a 3 mm Swimming Microrobot, Proceedings of 2004 IEEE International Conference on Intelligent Robots and Systems, IEEE, New York, p. 1746–1750.##Honda, T., Arai, K. and Ishiyama, K., (1999), Effect of Micro Machine Shape on Swimming Properties of the Spiral Type Magnetic Micro Machine, IEEE Trans. Magn., 35, p. 3688–3690.##Solovev, A. A., Mei, Y., Bermudez Urena, E., Huang, G. and Schmidt, O. G., (2009), Catalytic microtubular jet engines self propelled by accumulated gas bubbles, Small, 5 (14), p. 1688–92.##Hwang, G., Braive, R., Couraud, L., Cavanna, A., Abdelkarim, O., Robert Philip, I., Beveratos, A., Sagnes, I., Haliyo, S. and Regnier, S., (2011), Electroosmotic propulsion of helical nanobelt swimmers, The International Journal of Robotics Research, 30(7), p. 806–819.##Dreyfus, R., Baudry, J., Roper, M. L., Fermigier, M., Stone, H. A. and J. Bibette, (2005), Microscopic artificial swimmers, Nature, 437(7060), p. 862–865.##Yamazaki, A., Sendoh, M., Ishiyama, K., Ichi Arai, K., Kato, R., Nakano, M. and Fukunaga, H., (2004), Wireless micro swimming machine with magnetic thin film, Journal of Magnetism and Magnetic Materials, vol. 272, p. E1741–E1742.##Ghosh, A. and Fischer, P., (2009), Controlled propulsion of artificial magnetic nanostructured propellers, Nano Letters, 9(6), p. 2243–5.##Tottori, S., Zhang, L., Qiu, F., Krawczyk, K. K., Franco Obregon, A. and Nelson, B. J., (2012), Magnetic helical micromachines: Fabrication, controlled swimming, and cargo transport, Advanced materials, 24(6), p. 811–816.##Zhang, L., Abbott, J. J., Dong, L., Peyer, K. E., Kratochvil, B. E., Zhang, H., Bergeles, C. and Nelson, B. J., (2009), Characterizing the swimming properties of artificial bacterial flagella, Nano Letters, 9(10), p. 3663–7.##Kummer, M. P., Abbott, J. J., Kratochvil, B., Borer, R., Sengul, A. and Nelson, B. J., (2010), OctoMag: An electromagnetic system for 5 DOF wireless micromanipulation, IEEE Transactions on Robotics, 26(6), p. 1006–1017.##Martel, S., Felfoul, O., Mathieu, J.-B., Chanu, A., Tamaz, S., Mohammadi, M., Mankiewicz, M. and Tabatabaei, N., (2009), MRI based medical nanorobotics platform for the control of magnetic nanoparticles and flagellated bacteria for target interventions in human capillaries, The International Journal of Robotics Research, 28(9), p. 1169–1182.##Hyung Kim, D., Seung Soo Kim, P., Agung Julius, A. and Jun Kim, M., (2012 ), Three dimensional control of Tetrahymena pyriformis using artificial magnetotaxis, Applied Physics Letters, 100(5), p. 053702.##Kim, D. H., Liu, A., Diller, E. and Sitti, M., (2012), Chemotactic steering of bacteria propelled microbeads, Biomedical Micro devices, 14(6), p. 1009–1017.##Martel, S., and Mohammadi, M., (2010), Using a swarm of self propelled natural microrobots in the form of flagellated bacteria to perform complex micro-assembly tasks, in International Conference on Robotics and Automation, p. 500–505.##Behkam, B. and Sitti, M., (2006), Design methodology for biomimetic propulsion of miniature swimming robots, Journal of Dynamic Systems Measurement and Control, Vol. 128, p. 36-43.##Behkam, B. and Sitti, M., (2005), Modeling and testing of a biomimetic flagellar propulsion method for micro scale biomedical swimming robots. Proceedings of the IEEE/ASME International Conference on Advanced Intelligent Mechatronics, Monterey, USA, p. 37-42.##Brennen, C. and Winet, H., (1977), Fluid Mechanics of Propulsion by Cilia and Flagella. 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B, 178, p. 327–346.##Kennedy, J. and Eberhart, R.C., (1995), Particle swarm optimization, in: Proceedings of the IEEE International Conference on Neural Networks IV, p. 1942–1948.##Eberhart, R.C., Dobbins, R. and Simpson, P.K., (1996), Computational intelligence PC tools, Morgan Kaufmann Publishers, Boston.##Engelbrecht, A.P., (2002), Computational Intelligence: An Introduction, John Wiley & Sons, Chichester.##Engelbrecht, A.P., (2005), Fundamentals of Computational Swarm Intelligence, John Wiley & Sons, Chichester.##Eberhart, R.C. and Kennedy, J., (1995), a new optimizer using particle swarm theory, in: Proceedings of the Sixth International Symposium on Micro Machine and Human Science, p. 39–43.##Ratnaweera, A. and Halgamuge, S.K., (2004), Self organizing hierarchical particle swarm optimizer with time varying acceleration coefficient computation, IEEE Transactions on Evolutionary Computation 8 p. 240–255.## ##

Accidental Limit State of Submarine Pipeline: Trawl Gears Pull-Over Loads and Effect of Free Span 2 2 Submarine pipelines failures lead to oil spills in water and may even lead to explosions with heavy financial and environmental damages. Trawl gear is one of the main factors in the failure of the submarine pipelines. In this paper, sensitivity analysis is performed on influence of height and span length alternations on the response of pipeline against the traction caused by trawling pull-over load. The FE model is presented using OrcaFlex software including modeling of seabed, pipeline and trawl gear parameters. To model soil and reinforced concrete, nonlinear parameters are considered. To verify the models, DNV-RP-F111 and results of modeling by SAGE Profile software is used. The results indicated that increase in span gap resulted in the increase in pipeline responses, but with the increase in span length, only the lateral displacement exhibited a considerable increment. Finally, Maximum time for pipeline to fail and system response to become greater than the standard level has been calculated. 47 58 2017/05/62017/03/112017/07/12016/12/262017/04/24 1396/2/4 2017/11/252017/11/252017/11/252017/11/252017/11/25 1396/9/4 Sina Taghizadeh Edmollaii Sina Taghizadeh Edmollaii Faculty of Marine Engineering, Petroleum University of Technology iran s.taghizadeh@mnc.put.ac.ir Pedram Edalat Pedram Edalat Faculty of Marine Engineering, Petroleum University of Technology iran Edalat@put.ac.ir Submarine pipeline Pull-over load Free span Finite element analysis OrcaFlex Kawsar, M. R. U., Youssef, S. A., Faisal, M., Kumar, A., Seo, J. K., & Paik, J. K. (2015). Assessment of dropped object risk on corroded subsea pipeline. Ocean Engineering, 106, 329–340.##Mustafina, A., (2015), Anchor Damage Assessment of Subsea Pipelines - Optimization of Design Methodology, (Master's thesis in Offshore technology, University of Stavanger, Norway), Retrieved from http://hdl.handle.net/11250/1248742.##DNV GL, (2012), DNV-OS-F101 Submarine Pipeline Systems, Det Norske Veritas, Norway.##Bai, Y., Bai, Q., (2005), Subsea pipelines and risers, Oxford UK: Elsevier Ltd, p. 173-194.##DNV GL, (October2010), DNV-RP-F111 Interference between Trawl Gear and Pipelines, Det Norske Veritas, Norway.##Gjørsvik, O., Kjeldsen, S., Lund, S., (1975), Influences of bottom trawl gear on submarine pipelines, seventh annual offshore technology conference, p. 337-345.##7- Carstens, T., Kjeldsen, S., Gjørsvik, O., (1976), The conflict between pipelines and bottom trawls - some results from laboratory and field tests, Offshore north sea technology conference and exhibition.##Moshagen, H., Kjeldsen, S., (1980), Fishing gear loads and effects on submarine pipelines, Twelfth annual offshore technology conference, p. 383-392.##Bergan, P.G., Mollestad, E., (1982), Impact-response behavior of offshore pipelines, J Energy Resour-ASME, 104:325–9.##Guijt, J., Horenberg, J.A.G., (1987), Recent investigations concerning the effect of bottom trawl gear crossings on submarine pipeline integrity, Nineteenth annual offshore technology conference, p. 573–580.##Verley, R.L.P., Moshagen, B.H., (1992), trawl forces on free-spanning pipelines. Int J Offshore Polar.##Fyrileiv, O., Askheim, D., Verley. R., Rolsdorph, H., (2006), Pipeline-Trawl Interaction: Effect of Trawl Clump Weights, ASME. International Conference on Offshore Mechanics and Arctic Engineering.##Igland, R.T., Soreide, T., (2008), Advanced Pipeline Trawl Gear Impact Design, ASME, International Conference on Offshore Mechanics and Arctic Engineering, Volume 3: Pipeline and Riser Technology.##Teigen, P., Ilstad, H., Levold, E., & Hansen, K. (2009, January 1), Hydrodynamical Aspects of Pipeline Over trawling, International Society of Offshore and Polar Engineers.##Herlianto, I., Chen, Q., Karunakaran, D., (2012), Lateral Buckling Induced by Trawl Gears Pull-Over Loads on High Temperature/High Pressure Subsea Pipeline, ASME, International Conference on Offshore Mechanics and Arctic Engineering, Volume 3: Pipeline and Riser Technology.##Longva, V., Saevik, S., Levold, E., Ilstad, H., Teigen, P., (2011), Dynamic Simulation of Free-Spanning Pipeline Trawl Board Pull-Over, ASME, International Conference on Offshore Mechanics and Arctic Engineering, Volume 4: Pipeline and Riser Technology.##Van den Abeele, F., Galvan, B.C., Ramos, P., Muylle, J., (2013), Numerical simulation of the interference between trawl gear and offshore pipelines,6^th International Pipeline Technology Conference, Ostend.##Yohannes, B., (2012), Trawl Gear interaction with Subsea Pipelines, (Master's thesis in Offshore technology, University of Stavanger, Norway), Retrieved from http://hdl.handle.net/11250/183133.##OrcaFlex manual version 9.7a, Orcina, 2013.## ##

Investigation of the Pile Aging Effect of a Fixed Offshore Platform Located in Persian Gulf using Nonlinear Soil-Pile Interactions 2 2 The study about the jacket platforms in the past has revealed that the most of the collapse failures occur due to the lack of strength of the pile foundation. However, when the jacket platforms which have been collapsed due to extreme condition were looked into, it was found that most of them had their foundations intact. These contrasting facts can be explained with the help of the phenomenon called “aging of piles”. Aging effect of piles has been proven by experiments indicating gradual increase in pile capacity which is due to the thixotropic characteristics of clayey soils, leading to gradual improvement of soil clamping property. But due to lack of proper understanding and suitable techniques to incorporate them, these aging effects have been ignored during the pushover analysis. In this study, a simple technique of stepping up of the soil curves in order to accommodate the increase in capacity of pile foundation due to aging is utilized, and then the pushover analysis is performed using commercial software SACS. SPD19C (South Pars gas field Development, phase 19) is a new constructed jacket platform in Persian Gulf which is used as the case study in this paper. The platform is considered to be under the storm condition in 180º direction which is the worst condition. This study shows that the incorporation of pile aging effect results in the improvement the piles performance and Reserve Strength Ratio (RSR) about 10 percent. This research also has provided a deeper knowledge into the behavior of aged offshore jacket platforms. 59 64 2017/05/62017/03/112017/07/12016/12/262017/04/242017/05/27 1396/3/6 2017/11/252017/11/252017/11/252017/11/252017/11/252017/11/25 1396/9/4 Ghafour Emamverdizadeh beyg Ghafour Emamverdizadeh beyg Petroleum University of Technology iran g.emamverdi@mnc.put.ac.ir Abdolrahim Taheri Abdolrahim Taheri Petroleum University of Technology iran rahim.taheri@put.ac.ir Jacket Platform SACS Pushover Analysis Aging Effect Persian Gulf Nichols, N. W., Goh, T. K. and Bahar, H., (2006), Managing Structural Integrity for Aging Platform, in SPE Asia Pacific Oil and Gas Conference and Exhibition, Adelaide,Australia,.##George, J. M., Wahab, M. M. A., and Kurian, V. J., (2016), Changes in The Pushover Analysis of Offshore Jacket Platforms Due to The Incorporation of The Aging Effect of Piles, ARPN Journal of Engineering and Applied Science , vol. 11.##Gilbert, R. B., Chen, J. -Y., Materek, B., Puskar, F., Carpenter, J. and Young, A., (2010), Comparison of Observed and Predicted Performance for Jacket Pile Foundations in Hurricanes, in Offshore Technology, Houston, Texas, USA.##George, J. M., Wahab, M. M. A. and Kurian, V. J., (2015), Estimation of Aging Effects of Piles in Malaysian Offshore Locations, Journal of Engineering Science and Technology, (In publication).##El-Reedy, M. A., (2014). Marine Structural Design Calculations, United Kingdom: Butterworth Heinemann.##Clarke, J., (1993), Large-Scale Pile Tests in Clay, London: Thomas Telford.##Bogard, J. D. and Matlock, H., (1990), Applications of model pile tests to axial pile design, in Proceedings of the 22nd Annual Offshore Technology Conference, Houston Texas.##komurka, V. E., Wagner, A. B. and Edil, T. B., (2003), Estimating soil/pile set-up, The Wisconsin Highway Research Program (WHRP).##Lied, E. K. W., (2006), A Study of Time Effects on Pile Capacity NGI Report, Norwegian Geotechnical Institute, Norway.##Skov, R. and Denver, H., (1988), Piles TimeDependence of Bearing Capacity of Piles, in Proceedings of the 3rd international conference on the application of stress-wave theory to piles, Ottawa, Canada.##Bentley Systems, (2010). SACS Software Manual, From Engineering Dynamics Inc.##Narayanan, S. P. and Kabir, M., (2009), Structural Integrity Management for Fixed Offshore Platform in Malaysia, Malaysia: World Academy of Science, Engineering and Technology.##DIN, German Institute for Standardization, German: Deutsches Institut fur Normung.##API, (2013), Structural Integrity Management of Fixed Offshore Structures, American Petrolume Institute.## ##