PLANING HULL SEAKEEPING IN IRREGULAR HEAD SEAS
UDC 629.5.017/018.71 Summary The paper presents the results of planing hull seakeeping tests in irregular seas. The tested model belongs to a small systematic series developed at the University of Naples; it is a prismatic hull very similar to the well-known Fridsma’s models. The 16.7 degrees deadrise angle, length-to-breadth and load coefficient are representative of modern hull forms of pleasure boats. Tests in irregular waves have been performed at three speeds for one displacement in three sea states. The measured heave, pitch, acceleration at the centre of gravity and at bow have been analysed in the time domain and the results are presented in terms of significant values (the mean of 1/3 rd highest values). They are given in tabular and graphical form. Furthermore, the obtained results are commented with respect to the state of the art in planing hull seakeeping, and compared with the available experimental data from literature. The conclusions highlight the applicability of these data in design practice, commenting on trends and the range of significant parameters.
Resistance assessment of warped hullform
Abstract A series of hard chine planing hull forms was developed at Department of Naval Architecture, University of Naples. Three warped and one monohedral hulls were designed and four 6 ft long models were built. The models have the same transversal section at 0.25 L from the stern with 16.7 degrees deadrise angle. Warped models had deadrise angle linearly varying along the hull length. Aim of the experimental program is the evaluation of the effect of deadrise angle variation along the hull length on hydrodynamic resistance and on seakeeping although this work presents calm water performances only. The models have clear polycarbonate bottom to allow flow visualization and accurate wetted surface assessment. Resistance tests were performed for speed coefficient CV ranging from 0.56 to 3.92 and for two load coefficient values: CΔ=0.428 and 0.392. Reported results are wetted lengths of pressure area and whisker spray area, projected angles of stagnation line, wetted surface and whisker spray area, residual resistance coefficient, sinkage, presented in standard non-dimensional form, and running trim.
Chapter 1 – Nanotechnology: A Toolkit for Cell Behavior
Tissue engineering seeks to effectively manipulate cellular populations to improve the function of damaged or diseased tissues and organs. Many techniques can affect cell behavior; however, in order to maintain desirable function, scientists and engineers design solutions that are as biomimetic as possible. True biomimeticity is very challenging without the incorporation of nanotechnology. Since cells in human tissues are surrounded by a 3D hierarchical tissue extracellular matrix containing numerous nano components, a revolutionary change in tissue engineering is to explore biomimetic nanobiomaterials and advanced 3D nano/microfabrication techniques for creating novel tissue constructs and regulating cell behavior. This chapter will provide an overview of recent nanotechnology in tissue engineering applications. We will put special emphasis on integrating cutting-edge 3D nano/microfabrication techniques with nanobiomaterials for complex tissue and organ regeneration.