New Research Details

Question: What materials are needed to make the turbine and engine of both the boat and the generator? What type of turbines and engines ? What are the concept behind the creation of the turbine and electric generator?

Hydraulic Turbine also know as water turbine. A water turbine is a rotary engine that takes the movement of water and convert it into other forms of energy mainly electricity. It is a clean and renewable source of energy.
Water wheels have been used for thousands of years for industrial power. Their main shortcoming is size, which limits the flow rate and head that can be harnessed. The transformation from water wheels to modern turbines took about a hundred years. Development occurred during the Industrial revolution, using scientific principles and methods. They also made extensive use of new materials and manufacturing methods developed at the time.
Flowing water is directed on to the blades of a turbine runner, creating a force on the blades. Since the runner is spinning, the force acts through a distance (force acting through a distance is the definition of work). In this way, energy is transferred from the water flow to the turbine.
Water turbines are divided into two groups; reaction turbines and impulse turbines.
The precise shape of water turbine blades is a function of the supply pressure of water, and the type of impeller selected.
Reaction turbines
Reaction turbines are acted on by water, which changes pressure as it moves through the turbine and gives up its energy.
They must be encased to contain the water pressure (or suction), or they must be fully submerged in the water flow. Newton's third law describes the transfer of energy for reaction turbines.
Most water turbines in use are reaction turbines and are used in low (<30m/98ft) and medium (30-300m/98-984ft)head applications. In reaction turbine pressure drop occurs in both fixed and moving blades.
Impulse turbines
Impulse turbines change the velocity of a water jet. The jet impinges on the turbine's curved blades which change the direction of the flow. The resulting change in momentum causes a force on the turbine blades. Since the turbine is spinning, the force acts through a distance (work) and the diverted water flow is left with diminished energy.
Prior to hitting the turbine blades, the water's pressure (potential energy) is converted to kinetic energy by a nozzle and focused on the turbine. No pressure change occurs at the turbine blades, and the turbine doesn't require a housing for operation.
Newton's second law describes the transfer of energy for impulse turbines.
Impulse turbines are most often used in very high (>300m/984ft) head applications .
Pumped storage
Some water turbines are designed for pumped storage hydroelectricity. They can reverse flow and operate as a pump to fill a high reservoir during off-peak electrical hours, and then revert to a turbine for power generation during peak electrical demand. This type of turbine is usually a Deriaz or Francis in design. Types of water turbines


Various types of water turbine runners. From left to right: Pelton Wheel, two types of Francis Turbine and Kaplan Turbine
Reaction turbines:
Francis
Kaplan, Propeller, Bulb, Tube, Straflo
Tyson, Gorlov (Free-flow types)
Water wheel
Archimedean screw turbine
Impulse turbines:
Pelton
Turgo
Michell-Banki (also known as the Crossflow or Ossberger turbine)

Design and application

Turbine selection is based mostly on the available water head, and less so on the available flow rate. In general, impulse turbines are used for high head sites, and reaction turbines are used for low head sites. Kaplan turbines with adjustable blade pitch are well-adapted to wide ranges of flow or head conditions, since their peak efficiency can be achieved over a wide range of flow conditions.
Small turbines (mostly under 10 MW) may have horizontal shafts, and even fairly large bulb-type turbines up to 100 MW or so may be horizontal. Very large Francis and Kaplan machines usually have vertical shafts because this makes best use of the available head, and makes installation of a generator more economical. Pelton wheels may be either vertical or horizontal shaft machines because the size of the machine is so much less than the available head. Some impulse turbines use multiple water jets per runner to increase specific speed and balance shaft thrust.Runaway speed
The runaway speed of a water turbine is its speed at full flow, and no shaft load. The turbine will be designed to survive the mechanical forces of this speed. The manufacturer will supply the runaway speed rating
Maintenance
Turbines are designed to run for decades with very little maintenance of the main elements; overhaul intervals are on the order of several years. Maintenance of the runners and parts exposed to water include removal, inspection, and repair of worn parts.
Normal wear and tear includes pitting from cavitation, fatigue cracking, and abrasion from suspended solids in the water. Steel elements are repaired by welding, usually with stainless steel rod. Damaged areas are cut or ground out, then welded back up to their original or an improved profile. Old turbine runners may have a significant amount of stainless steel added this way by the end of their lifetime. Elaborate welding procedures may be used to achieve the highest quality repairs.
Other elements requiring inspection and repair during overhauls include bearings, packing box and shaft sleeves, servomotors, cooling systems for the bearings and generator coils, seal rings, wicket gate linkage elements and all surfaces.