NUCLEAR POWER REACTOR DEMONSTRATION MODEL

NUCLEAR POWER REACTOR DEMONSTRATION MODEL

The main use currently given nuclear energy is the electric power generation. Nuclear power plants are responsible for his process. The operation of a nuclear plant is identical to that of a thermal power station operating with coal, oil or gas except in the way of providing heat to the water to convert to steam. For this nuclear reactor heat is produced by the fission reactions of the fuel atoms.

The basic principle of operation of a nuclear power plant is based on obtaining heat energy through nuclear fission core combustible atoms. With this heat energy, which have a vapor of water, will convert into mechanical energy in a turbine, and finally convert mechanical energy into electrical energy by a generator .                                                             .

Nuclear fission occurs when a neutron strikes the nucleus of an atom and split it apart. Most of the nucleus of the original atom goes to form new smaller atoms. In addition, several neutrons may split off to form the original atom during fission. But the mass of all these neutrons and fission products does not add up to mass of original atom. That's because when the atom splits, some of its mass is converted directly into energy.

Nuclear reactors and warheads can employ the uranium isotope U-235. When the U-235 atom splits, it frees tower or three neutrons, which then fly off and split other U-235 atoms in close proximity, starting a chain reaction.

In warheads, the chain reaction multiplies exponentially, giving off a huge amount of energy at once in a nuclear explosion. In nuclear reactor a chain reaction must be controlled to create a safe, harvestable source of energy.

1. The Nuclear Reaction:

In the reactor vessel, cylindrical uranium pellets are stacked into long fuel rods. It is with in bundles of these rods that the chain reaction occurs. Together they are called the reactor. To keep the reaction under control: Very low concentration of U-235 is used in the reactor, so not every neutron will strike a nucleus. The retractable control rods, made of a material that absorbs neutrons, can be lowered into the reactor to siphon off neutrons  thatwould multiply the chain reaction. Much of the enegy released by the chain reactonis the manifested as heat. The fuel rods are placed inside a pressurized chamber full of water. Because this reactor vessel is kept at high pressure, the water will reach temperatures much greater than 100c.

2. Steam Generation:

This superheated water is pumped through a pipe that runs, like a heating element, through a second chamber called the stream generator is partially filled with clean water, which is boiled by the heated pipe running from the reactor vessel. The steam generator is also kept at high pressure (though it's lower than that of the reactor vessel.) 

 3. Electricity Generation:

Superheated steam force its way out of the steam generator. It cranks a turbine, which produces electricity. As the water in the steam generator boils, it also siphons heat away from the water in the pipe flowing to the reactor vessel. This helps to cool the reactor. In another type nuclear plant, called a Boiling Water Reactor, the steam powering the turbine comes directly from the reactor vessel. 

4. Steam Condensation:

After the steam crank the turbine, it is condensed back into a liquid as it runs over a pipe filled with cold water flowing from the cooling tower. It is then recycled into steam generator. The water from the cooling tower heats up during this process and some of it is released as steam. It is then replaced from a nearby body of water. 

 5. Self Regulation

Modem reactors are designed to be safe and self-regulation. In the same way that an airplane is designed to level out naturally after being jostled, reactor are engineered to maintain safe level of chain reaction under any circumstances.    

Applications of Nuclear  Energy:

Although nuclear energy is mainly used for the production of electricity in nuclear power plants.  But nuclear energy can be applied in many other sectors, such as: Industrial applications: for analysis and process control.

1. Medical applications: in diagnosis and therapy of diseases.

2. Applications in food-processing in the production of new species, conservation treatments of food, pest insects and vaccine preparation. 

3. Environmental applications: the determination of significant amounts of pollutants into the environment.

4. Other applications such as dating, which uses the properties of carbon-14 fixation to bone, wood or organic waste, determining their chronological age and applications in geophysics and Geochemistry, taking advantage of the existence of naturally occurring radioactive materials for fixing the dates of the deposits of rocks, oil carbon. 

The main drawback and what makes it more dangerous is it safe to use the responsibility rests with the people. Irresponsible decisions can lead to accidents at nuclear power plants but, even worse, can be used for military purposes as demonstrated in the history of nuclear energy in the first time that nuclear energy was used after appropriate investigations was to attack Japan in World War II with two nuclear bombs.

Uranium used in reactor has been enriched to create a higher concentration of U-235 than occurs in nature. Countries with the technology to enrich uranium for power can expand their capabilities to create high enriched uranium for wepons.Some reactor used plutonium,another weapons material or create it as a waste product. Even regular nuclear waste- the radioactive and heavy metals that are the products of fission-is dangerous, making it a concern every where nuclear power is used.

Nuclear reactors are an important carbon free source of power. We are likely to see a surge in there construction in the next few years.