Components of Nuclear Power Plant – Reactor Vessel

A nuclear reactor consists of various parts which carry out different functions related to heat generation by “burning” of nuclear fuel, but a housing is needed to contain all these parts and act as a covering for all these paraphernalia

Introduction

Just imagine if your beautiful body did not have the cover of the skin, and when you met any individual you could simply see through their various organs and into their "dirty" workings. This would certainly be not a very pleasing sight and would take out the very charm of human personality. This is not much different in the case of nuclear reactors as well. I cannot imagine going to a nuclear power plant just to find that the reactor core, fuel rods, control rods etc are all lying bare bones without any proper cover of enclosure. Hence the outside component of nuclear power plant is very important and is known as the reactor vessel.

Reactor Vessel

Vessels are often used to cook food, and though a nuclear reactor may not be cooking food directly for you, it certainly provides a source of an equally valuable food for the society: electrical energy. But apart from the cooking business there are a lot of functions which a nuclear reactor vessel has to perform and some of these are as follows.

It acts to enclose the various parts inside the reactor including the core, shield, reflector etc.
The coolant needs a passage to flow through the reactor so that it can be used to transfer the heat to the working fluid or the turbine directly, as the case may be, and this passage is provided by the reactor vessel.

To withstand the high pressure with exists inside the reactor and could be of the order of 200 kgf/cm2, to provide a safe working environment for all concerned.
Control of the nuclear reaction is absolutely necessary and this is done with the help of control rods. The reactor vessel provides a place to insert these control rods in the nuclear reactor and move them in or out of the reactor core depending on the requirements of power.

The Pressure Vessel

Although the reactor vessel has been compared to a cookery vessel in the common usage of the term, technically speaking it is more of a pressure vessel. There are legal implications associated with defining a pressure vessel and these vary with the country in which it is being used or manufactured. Different countries have different authorities which govern rules and regulations regarding pressure vessels and in the US this is done by the American Society of Mechanical Engineers Boiler and Pressure Vessel Code. The material used for the construction of a nuclear vessel is usually steel which would be expected as the material has to be very strong and resilient.

Pressure vessels of all kinds are subject to various tests to check for their strength against laid down standards which is very important to ensure safety of these vessels. This is moreso important in the case of nuclear reactor vessels which house source of intense raditaions and heat energy.

Hence we see that though a nuclear reactor vessel may not be performing any useful function direcly in the generation of electrical energy, it acts to hold together all major components of the power plant.

source:http://www.brighthub.com/

How Does a Nuclear Power Plant Work?

Today nuclear power plants have become major source of electricity for us. Externally the nuclear power plant looks like a dome, but it is interesting to know how a nuclear power plant works, what are the types of materials and equipment used, and so on. So just read this article to gain invaluable insight into the interesting world of the industry where power is extracted from the atomic level of matter.

Introduction

Whenever the term nuclear power plant is mentioned, it usually brings images of the Chernobyl disaster into mind, or related images of the nuclear technology triggered device which destroyed 2 cities of Japan during the Second World War. I agree that these incidents were very unfortunate and should have never happened in the first place, but believe me when I say that nuclear power is quite safe. Though nuclear energy has devastating capabilities such incidents or accidents mainly happen due to human errors of carelessness or prejudice. Otherwise nuclear technology is as safe as any other technology used to generate electricity and possibly much more effective in several situations. You will appreciate this viewpoint better once you know how does a nuclear power plant work?

The Energy Mass Ratio

In order to give you an idea about the scale of fuel quantities involved in a nuclear power station vis-à-vis traditional power stations, I ask you to imagine that around a pound of nuclear fuel like say Uranium gives the energy equivalent to burning a million gallons of gasoline. This should not come as a surprise since we have already learned that the energy released in a nuclear reaction is the equivalent of the mass change which takes place during the process. It is therefore huge compared to energy which is released as a result of combustion and related chemical reactions during traditional fuel burning.

How Does it All Work?

It is all very well to hear that tremendous energy lies within atomic particles, which is converted into electrical energy in a nuclear power plant. The million dollar question is- how is it achieved?
Well the nuclear energy isn’t converted directly into electricity but the heat released during the fission reaction is used to convert water into steam which in turn runs a turbine. The turbine turns the alternator which produces electricity to be fed into the power grid.
Of course the overall process is not as simple as it seems and there are several types of nuclear power plants which are classified according to different parameters, which will be discussed in separate articles on this topic.

One concept which must be well understood in context of nuclear power plants is the critical mass of the fuel used. We know that fission occurs whenever an atom splits into two or more components. Let us take the case of U 235 which splits to give 2-3 neutrons in the process which in turn strike other atoms and cause further splitting. This chain can only be sustained if the mass of U 235 is of a certain minimum value known as the critical mass. Below this critical value the reaction would ultimately die out, while if the critical value is exceeded it may result in the likes of an atomic bomb.

The above statement might have sent jitters down your spine, but just relax. Technology is quite advanced these days and so nuclear power plants simply do not blow up every other day as if they were nuclear bombs . The very few incidents that have occurred to date were mainly caused by carelessness.

Source:http://www.brighthub.com

How Much Do Engineers Earn?

Average starting salary offers vary by branch of engineering and by degree. For example, in 2006, the highest starting salary offers were in the following specialties: aerospace, agricultural, architectural, bioengineering and biomedical. The amount of the offer increased based on degree level attained.
Median annual earnings for several branches of engineering (U.S., 2006)

Electrical: $75,930
Civil: $68,600
Mechanical: $69,850
Computer Hardware: $88,470
Environmental: $69,940
Nuclear: $90,220
Biomedical: $73,930

source: http://careerplanning.about.com/od/occupations/p/engineer.htm

AGA 7 Calculation

AGA 7 takes a flowing volume, rate or flowing conditions and calculates base volume, base volume flow rate or volume correction factor. It requires flowing and base pressure, temperature and compressibility. Compressibility is calculated by your favourite equation of state, such as AGA 8.The algorithm for the calculation is extremely straightforward. It is really just the application of the real gas law to the measured volume.

For Flowing Volume:

Pf * Vf = Zf * n * R * Tf

so Vf = Zf * n * R * Tf / Pf

For Base Volume:

Pb * Vb = Zb * n * R * Tb
so Vb = Zb * n * R * Tb / Pb

Dividing the equations, we get

Vb/Vf = (Zb * n * R * Tb / Pb )/( Zf * n * R * Tf / Pf)
so Vb= Vf *(Zb * n * R * Tb * Pf) / ( Zf * n * R * Tf * Pb)

Changing the pressure and temperature doesn't change the number of moles, and R is a constant, so:

Vb= Vf *(Zb * Tb * Pf) / ( Zf * Tf * Pb)

S is defined as Zb / Zf
Fpm is defined as Pf / 101.56 kPa, or Pf / 14.73 PSIF
pb is defined as 101.56 kPa / Pb, or 14.73 PSI / Pb
Ftm is defined as 288.7056 Deg Kelvin / Tf, or 519.67 Deg. Rankin / Tf
Ftb is defined as Tb / 288.7056 Deg Kelvin, or Tb / 519.67 Deg. Rankin


So Fpm * Fpb = Pf / Pb
and Ftm * Ftb = Tb / Tf
So Vb = Vf * Fpm * Fpb* Ftm * Ftb * S

Calculate Fpm = Pf / 101.56 kPa (US base conditions, defined by AGA 7 spec)
Calculate Fpb = 101.56/Pb
Calculate Ftm = (15.55556 + 273.15)/Tf Deg. K (US base conditions, defined by AGA 7 spec)
Calculate Ftb = Tb / (15.55556 + 273.15) Deg. K (US base conditions, defined by AGA 7 spec)
Calculate S = Zb / Zf = Fpv2
Calculate BMV (base multiplier value) = Fpm * Fpb * Ftm * Ftb * S

Apply meter factor to BMV (Note: this is often done to the actual volume prior to using AGA 7.)

Calculate base volume Vb = Vf * BMV / 1000 (Converts M3 to E3M3, or Ft3 to MSCF)

Source: http://www.squinch.org/

What is Engineering?

Engineering is the science, discipline, art and profession of acquiring and applying technical, scientific and mathematical knowledge to design and implement materials, structures, machines, devices, systems, and processes that safely realize a desired objective or inventions.
The American Engineers' Council for Professional Development (ECPD, the predecessor of ABET) has defined engineering as follows:

“The creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under specific operating conditions; all as respects an intended function, economics of operation and safety to life and property.”

One who practices engineering is called an engineer, and those licensed to do so may have more formal designations such as European Engineer, Professional Engineer, Chartered Engineer, or Incorporated Engineer. The broad discipline of engineering encompasses a range of more specialized subdisciplines, each with a more specific emphasis on certain fields of application and particular areas of technology.

Mainly engineering can be broken down to several branches and disciplines. Although initially an engineer will be trained in a specific discipline, throughout an engineer's career the engineer may become multi-disciplined, having worked in several of the outlined areas. Historically the main Branches of Engineering are categorized as follows:

Aerospace Engineering - The design of aircraft, spacecraft and related topics.

Chemical Engineering - The exploitation of chemical principles in order to carry out large scale chemical processing, as well as designing new speciality materials and fuels.

Civil Engineering - The design and construction of public and private works, such as infrastructure (roads, railways, water supply and treatment etc.), bridges and buildings.

Electrical Engineering - The design of electrical systems, such as transformers, as well as electronic goods.

Mechanical Engineering - The design of physical or mechanical systems, such as engines, powertrains, kinematic chains and vibration isolation equipment.

With the rapid advancement of Technology many new fields are gaining prominence and new branches are developing such as Computer Engineering, Software Engineering, Nanotechnology, Tribology, Molecular engineering, Mechatronics etc.

These new specialties sometimes combine with the traditional fields and form new branches such as Mechanical Engineering and Mechatronics and Electrical and Computer Engineering. A new or emerging area of application will commonly be defined temporarily as a permutation or subset of existing disciplines; there is often gray area as to when a given sub-field becomes large and/or prominent enough to warrant classification as a new "branch." One key indicator of such emergence is when major universities start establishing departments and programs in the new field.

For each of these fields there exists considerable overlap, especially in the areas of the application of sciences to their disciplines such as physics, chemistry and mathematics.

Source: Wikipedia