An hierarchical approach to hull form design

As ship design tools become more integrated and more advanced analysis tools are introduced, the ability to rapidly develop and modify hull forms becomes essential. Modern hull design applications give an experienced user the ability to create almost any shape of hull. However, the direct manipulation of hull surface representations is laborious and may limit the exploration of design concept to the fullest extent. Transformation of parent forms and parametric hull generation tools can provide a quick solution, but neither method is conducive for innovative design. A hull design tool is required that can integrate the separate techniques creating a fair hull form surface that can be modified easily throughout the design process. This paper explores the concept of separating the hull surface into global and local features by establishing a hierarchical definition structure and introduces some of the benefits of this approach

SHAPE Project Hydros Innovation: Automatic Optimal Hull Design by Means of VPPApplications on HPC Platforms

Hydros is an Engineering & Research Swiss company founded in 2007 with several patented designs in the field of marine and sailing yachting. In recent years Hydros is exploring new market segments such as yachts and super-yachts hull design. The usage of HPC resources and open-source softwares can be a valuable tool in the massive shape design optimizations usually performed by Hydros. The main scope of the proposed SHAPE pilot was therefore to evaluate the feasibility of automatic optimal hull design on HPC infrastructure and the impact of such a workflow on the day-by-day work of Hydros personnel. To accomplish this task the project was subdivided into a set of steps including a preliminary validation of a 2DoF CFD analysis of an industrial hull design using open-source code, the scalability test of commercial and open-source CFD code for hull 2DoF modelling, the coupling of the CFD result into an existing CAD modification and optimization loop, and finally the running of a complete optimization loop for an industrial hull design using open-source code on the HPC platform and usability evaluation of the solution provided

Pressure Hull Design Methods for Unmanned Underwater Vehicles

This paper describes design methods for the plastic hull of an Unmanned Underwater Vehicle (UUV), with a particular focus on its cylindrical body and nearly spherical domes at the ends. With the proposed approach, the methodologies reported in the literature were compared, and suitable modifications and improvements were investigated and implemented to extend the classical theories and data to this case study. The investigated underwater vehicle, named FeelHippo, was designed and assembled by the Department of Industrial Engineering of the University of Florence. Its main hull is composed of an extruded PMMA (PolyMethyl MethAcrylate) cylinder and two thermoformed PMMA domes. Breakage of the hull results in destructive phenomena, namely, yielding and buckling. An experimental campaign and FEM (Finite Element Method) analysis were carried out to complete the theoretical study, and the collapse pressures were compared with the derived design values. In conclusion, the proposed innovative method is a lean and effective technique for designing underwater hull domes and predicting the collapse pressures

Hull Design for ROV with Four Thrusters (X4-ROV)

In this research, an X4-ROV consisting of four thrusters is design to develop a small ROV which does not have any rudders for an observation class unmanned underwater vehicle system. Each thruster is arranged at equal intervals to the same plane, and the attitude motions of a roll, a pitch and a yaw, and the translational motion forward are realizable by changing the rotational speeds of four thrusters. In this paper, the construction of an X4-ROV system and the motion method are described, together with the added mass. A torpedo hull shape with four thrusters is draft using solidworks for fabrication of hull (body) shape using a 3d printer. The operator will communicate with ROV via open source platfor

A practical concept for powered or tethered weight-lifting LTA vehicles

A concept for a multi-hull weightlifting airship is presented. The concept is based upon experience in the design and handling of gas-filled balloons for commercial purposes, it was first tested in April, 1972. In the flight test, two barrage balloons were joined side-by-side, with an intermediate frame, and launched in captive flight. The success of this flight test led to plans for a development program calling for a powered, piloted prototype, a follow-on 40 ton model, and a 400 ton transport model. All of these airships utilize a tetrehedric three-line tethering method for loading and unloading phases of flight, which bypasses many of the difficulties inherent in the handling of a conventional airship near the ground. Both initial and operating costs per ton of lift capability are significantly less for the subject design than for either helicopters or airships of conventional mono-hull design

Parametric search and optimisation of fast displacement hull forms using rans simulations of full-scale flow

Abstract. A methodology to derive parametric hull design candidates with a specified displacement and initial stability is introduced. A gradient-free search and optimisation algorithm coupled to a RANS CFD solver is then used to identify efficient pure-displacement hull shapes with minimal hydrodynamic resistance operating in the transition speed region without relying on dynamic lift

Parametric modelling of Malaysian teeth template using computer aided design

This study explored a new method and process of design denture using CAD technology to develop a template of a complete denture. Computer aided design were used as a tool of the design process. Occlusion curve was set up as variable as to follow patient size. The maxilla and mandible teeth arrangement were treated as a template of Malaysian user. The accuracy of design is the main aspect of concern that match the patients' data so that the outcome product would be suitable with maximum comfort for the patient. The product of design template will be matched with the conventional method to compare the tolerance between both. The new design template helps to reduce the time consumption of conventional carving method. The final output of 3D geometry teeth templates design will represent the patient details

Preliminary Design and Optimization of Subsea Shuttle Ring-Reinforced Pressure Hull using the Response Surfaces Methodology

Master's thesis in Marine and Offshore TechnologyPipelines and tanker ships are the main hydrocarbons transportation systems operate in the North Sea. Oil and gas fields in remote and harsh locations cannot be served well by these two transportation systems. One of the main obstacles is the weather. In an effort to answer the above needs, a new hydrocarbon transportation system is developed which is expected to combine the advantages of pipeline and tanker technology while eliminating the weaknesses of both technologies. The new alternative hydrocarbon transportation system came in the form of submarine called subsea shuttle. Subsea shuttle is designed to be able to operate at certain depths. Thus, the hydrostatic load encountered will be varied and high. This challenge requires a pressure hull design that is able to withstand the environmental loads. Otherwise, the buckling may occur. A pressure hull that is well designed, usually large and heavy. This will cause the development of the subsea shuttle to be expensive and inefficient. The optimization method can be used to maximize pressure hull performance without significantly increasing its size and weight. By determining the key parameters that affect the pressure hull, an optimum pressure hull design can be obtaine