Wyniki wyszukiwania - BazTech

1

Numerical Analysis of the Contact Forces Generated on a „Hiload DP1” Prototype Attachment System at Calm Sea

Rutkowski G.

Zeszyty Naukowe Akademii Morskiej w Gdyni

|

2014

|

nr 87

22--32

EN

In this paper author describes the characteristics of a Hiload Technology installed on board „Hiload DP1” unit, known as the next-generation offshore loading solution (i.e. transferred buoy) for crude oil. The core technology was built up around the patented Remora Attachment System, which is similar to the Remora fish and equipped with a „suction cup”, known as „a based attachment system”, capable of transferring several thousand tons between the „Hiload DP1” unit and the connected object i.e. the bottom of a conventional tanker. In this paper author depicts the basic characteristics of a „Hiload DP1” prototype attachment system with the operational tests and the numerical analysis of a contact forces generated on such system at calm sea.

PL

W niniejszym artykule przedstawiono krótką charakterystykę nowatorskiej technologii Hiload zastosowanej na prototypie statku nowej generacji „Hiload DP1”. Technologia ta opiera się na opatentowanym przez firmę Remora SA systemie „przyssawek dennych” (Remora Attachment System), który umożliwia sprawne dokowanie statku do burty (dna) innych jednostek morskich, umożliwiając jednostkom konwencjonalnym ich odholowanie do punktów zbornych i/lub dynamiczne ich pozycjonowanie w wyznaczonym obszarze operacyjnym, wspomagając ich operacje ładunkowe w sektorze off-shore. Istota działania systemu jest przy tym tożsama z systemem przyssawek skórnych stosowanym przez ryby remora. W artykule skupiono się na analizie numerycznej sił kontaktowych statycznych, wygenerowanych w systemie „przyssawek dennych” statku „Hiload DP1” na wodzie spokojnej.

2

Utilization of an active and/or passive heave compensation in the equipment of dynamic positioning vessels

Herdzik J.

Journal of KONES

|

2014

|

Vol. 21, No. 2

89--95

EN

DP vessels have a possibility to maintain their position or heading by using thrusters and propellers but the heave compensation is not possible that way. Heave compensation is a technique used to reduce the influence of waves on a hull or only a part of an equipment inside the hull. There are two types of heave compensation: passive (PHC) and active (AHC). Due to limit, the energy demand the hybrid heave compensation (HHC) is often in use. The offshore activities needed the compensation to some extend (level) could be drilling, handling loads in cranes or pipe laying. Different types of Heave Compensator Systems (HCS) are used to compensate for these movements. Safety of these offshore activities is so important that the area of power (using external energy) and non-power (using only the energy of wave movement) drives are quickly developed. The heave compensators allow increasing the weather window and better making use of the offshore vessels. The expected level of decreasing the vessel heave in compare to work equipment is from 5 to 50 times. Active compensation by hydraulic motor needs its active run for motion compensation and the system ought to be equipped with accelerometer senses of ship movement. Computing algorithms and the choice of control method are principal in HCS performance. In the article, it was shown examples of different types of compensators with their advantages and disadvantages and their utilization.

3

Evaluating criteria for DP vessels

Herdzik J.

Journal of KONES

|

2013

|

Vol. 20, No. 4

117--122

EN

The paper presents the evaluating criteria for DP vessels. A few persons tried to give a simple tool for comparing the station keeping capability between different ships. It was started in the seventies when most vessels claiming to have a DP system would be carried away by the current only (the limit was 1.5 up to 2 knots). Mainly DNV and ABS, next IMO prepared the calculating methods for DP system evaluation during the design process to receive the DP class 1, 2 or 3. The regulations may help but it’s still only rough estimate. One of them is the most popular. It is the capability plot presenting at preliminary the polar diagram with number envelops, showing the vessel’s capability to keep position or heading with a certain combination of thrusters in operation. The number, type, total power (or thrust) and location of thrusters are vital for estimating the DP capability from the propulsion system. The other equipment is only accessories assisting the DP system. At the end the sea trial may check and confirm the DP class of the vessel. The real capability for station keeping will be verified during normal operation, essentially during emergency situations like electric network faults, propulsion system failure up to damages and fire. It is needed some indexes or parameters during the design process to avoid serious faults. The paper is a probe of becoming familiar with chosen criteria.

4

Dynamic positioning systems during emergency or unexpected situations

Herdzik J.

Journal of KONES

|

2013

|

Vol. 20, No. 3

153--159

EN

The paper presents the consequences for DP systems during emergency or unexpected situations like failure one or more gensets, failure one of propulsion unit, overloading electric system, getting off the course, vessel abandonment of DP work, etc. The design of DP system takes into consideration required the DP system class, the requirements of adequate classification society under supervision the ship is built. It is necessary to fulfil the system redundancy in normal operation states. When failures occur in the vessel systems, it changes the possibility of DP work. There are three DP alert levels: green, yellow and red needed the proper responses. It was prepared required procedures for crew according to ISM Code, IMCA and IMO regulations. For the vessel safety, it is important the training process all crew members, especially one of the navigating officer as DP operator and one of the engineer or electrician. They ought to know their duties during alarms, exercises and real situations, especially in DP operation. The human factor ought to be taken into account as well. The DP operator may directly initiate the loss of vessel position or interact with technical failure events, which then contribute to a loss of vessel position. The important problem to solve is how to avoid emergency situations. It’s time for quick and important decisions for further vessel’s activity.

5

Models of DP systems in full mission ship simulator

Zalewski P.

Zeszyty Naukowe / Akademia Morska w Szczecinie

|

2010

|

nr 20 (92)

146-152

EN

The paper presents modelling principles of DP systems integrated into the modernized full mission ship simulator of Kongsberg Polaris® type at Maritime University of Szczecin. Comparisons to real systems and research possibilities are given. Basing on the effects and conclusions obtained from scientific-research works performed by marine traffic engineering staff until now, the advantages of modernization of "full mission simulator" have been shown.

PL

W artykule przedstawiono modele systemów dynamicznego pozycjonowania (DP) w wielozadaniowym symulatorze statku typu Kongsberg Polaris® w Akademii Morskiej w Szczecinie. Zaprezentowano porównania z rzeczywistymi systemami i możliwości badawcze. Na podstawie rezultatów dotychczasowych prac naukowo-badawczych realizowanych w Instytucie Inżynierii Ruchu Morskiego AM w Szczecinie przedstawiono zalety modernizacji wielozadaniowego symulatora manewrowo-nawigacyjnego statku.