In recent years, research has been conducted on reducing resistance by adding steps the bottom of high-speed craft. The most significant issue in design multi-stepped planing craft is selection an appropriate step configuration, i.e., geometry, location, and height. This requires a general knowledge hydrodynamic behavior each configuration. Although towing tank test effective method to predict ...

A practical cavitator design method for straight-running-type supercavitating torpedoes was developed in this paper. Design requirements were first drawn terms of torpedo performance characteristics, such as maximum range and motion stability. This determines the optimum satisfying that not only minimize total drag torpedo, extending range, but also provide hydrodynamic forces required straight...

Abstract The International Towing Tank Conference (ITTC) suggests that determining the variations of propulsion efficiency can be achieved by model tests may costly and inefficient. This is reason why this paper investigates variation factors under various ship loading conditions computational fluid dynamics (CFD). study proposed a non-iterative method for load reduced time. CFD software Star-C...

Owing to environmental regulations, ships are equipped with a pre-swirl stator (PSS), which is one of the most effective energy-saving devices (ESDs) that widely applied various kinds ships. It improves energy efficiency by recovering rotational kinetic propeller aid PSS placed in front propeller. In this study, an asymmetric system 2500 TEU eco-friendly liquefied natural gas (LNG) fuel feeder ...

Thirty-five years ago, B.F. Skinner (1976) lamented a decreasing trend in the prevalence of cumulative records in the Journal of the Experimental Analysis of Behavior ( JEAB). The editorial began with the two memorable lines, ‘‘Evidently we have not long to wait for an issue of JEAB without a single cumulative record! I shall not miss the records so much as the kinds of experiments that could s...

Triboelektrostatická separácia minerálnej substancie zo slovenského uhlia V článku sú diskutované niektoré technické aspekty triboelektrostatickej separácie a výsledky aplikácie tohto postupu pri úprave troch typov uhlia, konkrétne energetického uhlia z Cígľa, Handlovej a Novák. Bolo zistené, že účinnosť separácie veľmi úzko závisí na druhu separovan uhlia. Prvé výsledky preukázali súvislosť me...

As members of the derived teleost fish clade Scombridae, mackerel exhibit high-performance aquatic locomotion via oscillation of the homocercal forked caudal fin. We present the first quantitative flow visualization of the wake of a scombrid fish, chub mackerel Scomber japonicus (20-26 cm fork length, FL), swimming steadily in a recirculating flow tank at cruising speeds of 1.2 and 2.2FL s(-1)....

In spring 2006, Sierd de Vries and I were contacted by Professor Stive about an Australian surfboard manufacturer, Greg Webber, searching assistance in the development of a new invention; a circular pool with surfable waves generated by ship-like hulls. Soon the contact was established and it turned out to be an interesting research project. The results of research are documented in two theses....

Efficient swimming of biologically carangiform robotic fish has been investigated by using a novel experimental method. The laboratory robotic fish model, which follows an exact replica of Saithe, is self-propelled on a servo towing system. The forward towing speed is determined by the fluid force acting on the robotic fish, as the fish undulates its body in the water. The importance of the sel...

Submitted for the DFD15 Meeting of The American Physical Society Optimizing an undulating magnetic microswimmer for cargo towing1 YIZHAR OR, EMILIYA GUTMAN, Technion Israel Institute of Technology — One of the promising applications of robotic microswimmers is towing a cargo for controlled drug delivery, micro-surgery or tumor detection. This capability has been demonstrated by the magnetically...