Coarse mesh finite element model for cruise ship global and local vibration analysis

Abstract

This paper presents a practical procedure for creating finite element (FE) model for vibration analysis of cruise ships.The most preferable FE modelling approaches are studied and discussed through case analysis of common ship structure, which covers the range from low to high frequencies. The application of homogenized equivalent single layer (ESL) theory based equivalent element for stiffened panel is extended to local forced vibration analysis, where inertia induced interaction between plate and stiffener occurs. Modal method is used with an energy-based correction for accounting the plate-stiffener interaction into modal properties. Case study results reveal that mesh density of one 4-node element per web frame is suitable for global FE-model when vibration analysis is limited to global hull girder modes. For such modes it is sufficient to only include membrane stiffness of the stiffened panels. For investigating the response of higher frequencies, bending properties of stiffened panel should be included and mesh density should be at least two elements per web frame. Then forced vibration analysis can be performed with excellent accuracy up to frequencies about one third of the local plate natural frequencies between the stiffeners. Beyond that, influence of local plate vibration becomes more significant in panel vibration, making the ESL-theory based element limited. With the applied correction method, the validity of the ESL-model can be extended to approximately two thirds of the local plate natural frequency.

Collision Analysis of a Self Propelled Oil Barge’s (SPOB) Using Finite Element Method

“…The primary data collected, among others, are in Table 1 and Table 2 The meshing process is carried out to adjust the distance between elements, which must be analyzed using finite element-based software before proceeding to the processing stage. [5] [18] In the meshing steps carried out as follows, Click Mesh on the Outline then on the Detail of "Mesh" in the lower left corner, in the Defaults the load used on the model of the ship hitting a jetty that is not equipped with fenders and the ship hitting a jetty equipped with fenders, namely using the calculation of the impact force which has been calculated using equation (2.1) and using speed variations of 0,5m/s, 1m/s, and 2m/s where the results can be seen in Table 3. The load used on the model of the ship hitting a jetty that is not equipped with fenders and the ship hitting a jetty equipped with fenders is using the calculation of the impact force which has been calculated using equation 1 and using speed variations of 0.5m/s, 1m/s, and 2m/s where the results can be seen in Table 3.…”

Karakteristik Getaran Pada Dinding Kapal Penumpang Bermaterial Fiber Reinforced Plastic Akibat Operasional Mesin Induk

“…Analisis getaran lokal dilakukan untuk memprediksi lokasi kritis struktur akibat resonansi yang terjadi dengan metode Finite Element Analysis (FEA) [12]. Amplitudo wujud dari displasemen dalam satuan mm yang terjadi akibat adanya getaran sebagai pengganggu dijadikan alat ukur.…”

Structural Analysis of Deck Reinforcement on Composite Yacht for Crane Installation

“…The ESL (equivalent single layer) method simplifying this approach has been applied in relevant works. Putranto et al presented the ESL approach for the ultimate strength assessment of the ship hull girder in numerical FEM simulations [21], while Avi et al performed a cruise ship vibration analysis using a coarse mesh FEM model, with the ESL-theory-based element being limited to local plate natural frequencies [22].…”