Water Turbines.

A Francis Turbine runner, rated at nearly One million HP (750MW)

A Propeller type runner rated 21 MW

Kaplan Turbine and Electrical Generator Rated away View.

A water turbine is a rotary engine that takes energy from moving water. Water turbines were developed in the nineteenth century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy source

Theory of operation

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.

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. They are used in low and medium 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 (impulse) 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 head applications.

Step Brothers of my workmate!!!???

Picture of a turbojet

A jet engine is a reaction engine that discharges a fast moving jet of fluid to generate thrust in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, pulse jets and pump-jets. In general, most jet engines are internal combustion engines but non-combusting forms also exist.

In some common usage, the term 'jet engine' generally refers to an internal combustion duct engine, which typically consists of an engine with a rotary (rotating) air compressor powered by a turbine ("Brayton cycle"), with the leftover power providing thrust via a propelling nozzle. These types of jet engines are primarily used by jet aircraft for long distance travel. The early jet aircraft used turbojet engines which were relatively inefficient for subsonic flight. Modern subsonic jet aircraft usually use high-bypass turbofan engines which help give high speeds as well as, over long distances, giving better fuel efficiency than many other forms of transport.

About 7.2% of the oil used in 2004 was ultimately consumed by jet engines. In 2007, the cost of jet fuel, while highly variable from one airline to another, averaged 26.5% of total operating costs, making it the single largest operating expense for most airlines.

NOKIA E75 and its advantages.

It's email on the go with E75

First, there was mobile phone sets with basic programmes only for making calls and sending messeges, then came handsets with cameras and after that the internet. Although it felt great to surf on the tiny screen but emails were never that good. It always felt that emails were better on PCs or Notebooks than handsets, untill Nokia E series hit the market. After that the whole concept of mobile email changed and it got better when E75 came, the latest E series from Nokia.

Promising to offer the benefits of full desktop email functionality in a mobile handset, the E75 was launched for the Bangladesh market on April 26. It is the first device to offer the latest Nokia messaging email user interface, which makes the email experience easier than ever .Unlike other E-series handsets, the E75 features a slide-out Qwerty keyboard and two customisable home screen views offering business and personal user interfaces. When the E75 is open to display the QWERTY keyboard it becomes 80mm wide. The handset can be used in a horizontal or vertical position, obviously if you are typing a text message you would want to use the QWERTY keyboard so would therefore be using the E75 in a horizontal position.

The complete integration of its email and messaging services would allow for an efficient three-step email setup. The E75 has also been configured to offer access to both corporate and consumer email accounts, including Yahoo Mail, Gmail, Hotmail, Mail for Exchange and IBM Lotus Notes Traveller. The handset also offers integration with Nokia's web-based Ovi services, including Ovi Files for storing and accessing files and documents on a PC even when it is offline.

The phone has a pricetag of $ 400 for the market. So check it and click on adds to help me buy one......

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