Aeration Effects on Impact: Drop Test of a Flat Plate

Verbatim reproduction or republication of the papers or articles or part of the articles (e.g., figures or tables) by their authors, after the publication or presentation at the ISOPE meetings and journal, is permitted by the International Society of Offshore and Polar Engineers (ISOPE), provided the full credit is given to the authors, to the publisher, The International Society of Offshore and Polar Engineers (ISOPE), and to the Conference, Symposium or Journal - more specifically not to remove the copyright imprint on page 1 of the paper. The permission does not extend to copying for resale and to re-copyrighting the whole or part of the papers. Posting on your organization's website of the paper(s) you specified is allowed only where only your organization's employees including the students can view free of charge the paper authored or co-authored by your organization's employees, and www.isope.org is provided for the paper(s) in the ISOPE proceedings or journals. Regards, Prof. Jin S Chung Executive Director isope, 495 North Whisman Road, Suite 300 Mountain View, California 94043-5711, USA T 1-650-254-1871; F 1-650-254-2038; [email protected] [email protected], www.isope.org www.deepoceanmining.orgAeration effects on impact have been investigated by dropping a flat plate onto the water surface, in which the water is aerated to various degrees. An experimental study has been carried out in the newly commissioned Ocean Basin at Plymouth University’s COAST Lab. The falling block comprises a rigid impact plate connected to two driver plates and its total mass can be varied between 32 kg and 52 kg. The impact plate is 0.25m long, 0.25 m wide and 0.012 m high. The impact velocity is varied between 4 m/s and 7 m/s. Preliminary results of the impact tests are presented here. Visualised results show that there are significant differences between jet formation after impact of the plate in pure water and in aerated water. There is significant reduction of the maximum pressures from those measured in pure water to those measured in aerated water

A stable and accurate control-volume technique based on integrated radial basis function networks for fluid-flow problems

Radial basis function networks (RBFNs) have been widely used in solving partial differential equations as they are able to provide fast convergence. Integrated RBFNs have the ability to avoid the problem of reduced convergence-rate caused by differentiation. This paper is concerned with the use of integrated RBFNs in the context of control-volume discretisations for the simulation of fluid-flow problems. Special attention is given to (i) the development of a stable high-order upwind scheme for the convection term and (ii) the development of a local high-order approximation scheme for the diffusion term. Benchmark problems including the lid-driven triangular-cavity flow are employed to validate the present technique. Accurate results at high values of the Reynolds number are obtained using relatively-coarse grids

Free vibration analysis of laminated composite plates based on FSDT using one-dimensional IRBFN method

This paper presents a new effective radial basis function (RBF) collocation technique for the free vibration analysis of laminated composite plates using the first order shear deformation theory (FSDT). The plates, which can be rectangular or non-rectangular, are simply discretised by means of Cartesian grids. Instead of using conventional differentiated RBF networks, one-dimensional integrated RBF networks (1D-IRBFN) are employed on grid lines to approximate the field variables. A number of examples concerning various thickness-to-span ratios, material properties and boundary conditions are considered. Results obtained are compared with the exact solutions and numerical results by other techniques in the literature to investigate the performance of the proposed method

A continuum-microscopic method based on IRBFs and control volume scheme for viscoelastic fluid flows

A numerical computation of continuum-microscopic model for visco-elastic flows based on the Integrated Radial Basis Function (IRBF) Control Volume and the Stochastic Simulation Techniques (SST) is reported in this paper. The macroscopic flow equations are closed by a stochastic equation for the extra stress at the microscopic level. The former are discretised by a 1D-IRBF-CV method while the latter is integrated with Euler explicit or Predictor-Corrector schemes. Modelling is very efficient as it is based on Cartesian grid, while the integrated RBF approach enhances both the stability of the procedure and the accuracy of the solution. The proposed method is demonstrated with the solution of the start-up Couette flow of the Hookean and FENE dumbbell model fluids