The sea is a vital natural resource of humanity in general and of the State of Israel in particular. Associate Professor Netai Dreamer has lived and breathed the sea since he was 14 years old, and now he is joining the Faculty of Mechanical Engineering, hoping to breathe life into the field of marine engineering and return it to the status of a major in the faculty.
The sea is a vital natural resource of humanity in general and of the State of Israel in particular. Associate Professor Netai Dreamer has lived and breathed the sea since he was 14 years old, and now he is joining the Faculty of Mechanical Engineering, hoping to breathe life into the field of marine engineering and return it to the status of a major in the faculty.
According to him, the marine environment is used for transportation, food production, energy production, sports and leisure activities and is a huge potential for residential and industrial areas. Factors for a growing need for marine engineering in Israel, which have arisen recently, are: studies to establish artificial islands to solve the shortage of land, the discoveries of energy in the sea, the need to develop ports in light of the constant increase in the size of ships, security needs that increase the equipment and activity of the navy, the evacuation of aquaculture farms from protected water areas which requires dealing with the open sea and the accelerated development of autonomous vessels in which "Rafael" leads.
Since the sea is not man's natural environment, the utilization of the great potential inherent in it is based on engineering technology which advances conservatively, but with sure steps. Marine engineering is based on applied experience and any deviation from the space proven in experience is done gradually and with the backing of engineering research and development. Although the development of the sea is vital and critical to the State of Israel, it is still not among the strongest countries in this field. The Technion and its Faculty of Mechanical Engineering have the ability and tools to change this situation.
Design in a marine environment is the common denominator for designing buildings and facilities that need to function in a marine environment, such as ports, platforms for extracting natural resources from the sea, vessels, floating structures, structures based on the seabed and aquaculture facilities. Design in a marine environment is based on recognition and understanding of the marine environment and the ability to perform an engineering analysis of the action of the sea on the structure. Factors controlling the action of the sea on the structure are hydrostatic pressure, waves and currents.
The phenomenon of hydrostatic pressure is relatively simple to calculate and apply and is critical to the efficient functioning of the structure (buoyancy and stability). The main interest and challenge originates from the waves, which are enormously powerful and appear randomly. For a reliable evaluation of wave data for the design of a marine facility, a base of measured wave data for 20 years is necessary, from which it is possible to derive, by statistical analysis, wave parameters and characteristics for the design of the structure. In any case, the design criterion will be probabilistic. That is, the structure is designed for an extreme sea condition, which during the planned existence of the structure will have a small probability of deviation from it. Seasoned sailors know structures that fell apart during or after their construction and their saying is known that "for every naval structure the sea may appear which will fail it".
The most difficult environment for marine structures is the crisis area and it is desirable to avoid building structures in this area. When a wave advances from the open sea to shallow water it becomes steep (high and short) until it loses stability and breaks with great force. When it meets a structure before it breaks, a huge mass of water collides with the structure, which will cause pressures on the order of tens of tons per square meter. To illustrate - useful pressure for a floor plan in a banquet hall is about half a ton per square meter, and for a cargo dock in the port about five tons per square meter. Interesting ways to deal with the pounding of the waves in the structure are a porous structure or a flexible structure.
A vessel can float on the surface of the water (surface vessel) or dive. A slow surface craft will be in equilibrium with hydrostatic buoyancy. Hydrodynamic lifting forces will act on a fast vessel and it can glide on the surface of the water (surfing boat) or hover on underwater wing-like lifting surfaces (fin) or above an air cushion (hover).
A marine facility can be based on the seabed or float. The floating facility can be tied to ground anchors or held in place by an array of thrusters. The choice is made according to the depth of the water and the needs.
Since 1986, Associate Professor Dreamer has been involved in the development and design of facilities for aquaculture, which over time are exposed to more extreme sea conditions. For example - the sea cage farm for growing fish was designed for a wave with a maximum height of four meters and after its evacuation for environmental reasons, the "Ardag" company has to deal with the open sea off Ashdod using subplex systems that have already been exposed to waves with a height of 12 meters and are a global breakthrough in dealing with fish farming in the open sea.
Together with his father, the late Moshe Dreamer, he designed the underwater observatory in Eilat. Professor Dreamer carried out the naval architecture for "Raphael" unmanned sailing vessels. He also designed a terminal for roller coasters in the port of Haifa and as part of his role as director of the Technion's Israel Institute for Marine Engineering Research - he was responsible, among other things, for the laboratory experiments to test the hydraulic stability of the breakwater at the tributary port in Ashdod.
Already when he was 14 years old, he worked as a draftsman in the office of his father, who was a ship engineer, served in the navy as a submarine commander and is an experienced surfer and yachtsman.
Associate Professor Nethai Dreamer brings his love for the sea and his extensive experience in this field to the Faculty of Mechanical Engineering.
One response
In the absence of an educational framework in Israel, those interested in marine engineering are forced to migrate to Europe or the USA to study the profession and do not receive any institutional support for accumulating and increasing knowledge and experience in this important field.