Heat transfer from high temperature heated surfaces finds considerable application in engineering. Because of its large number of applications in industries, considerable efforts have been made by researchers to investigate various aspects of the heat transfer and its fundamental principles involved. Fluid flow problems involving heat transfer viz. in presence of convention and radiation represents an idealization of many meaningful problems in engineering practice. Due to the presence of higher level of temperature required in many system like boiler, nuclear reactor; the effect of radiation heat transfer increases. So, there becomes a need of including radiative effect of the participating medium and also their boundary conditions. Keeping this in mind, an attempt was made to investigate the heat transfer in the Indian Pressurized Heavy Water Reactor (IPHWR) during Loss of Coolant Accident (LOCA) with low steam flow. This study will help in estimating the safe working limits for the heat dissipation in the reactor.
A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. That nuclear power plant is similar to that of conventional power plant where the boiler is replaced by a nuclear reactor. As is typical in all conventional thermal power stations the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity. In a typical nuclear reactor the reactor core acts as heat exchanger, as the heat is generated by nuclear reaction, the generated heat is transferred to the primary cooling medium which is heavy water (D2O). Outside the reactor core, the primary coolant exchanges heat with the secondary fluid (water) to generate steam to be used in...
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...appen at a time (Gopal et al., 2010).
India’s current Nuclear Power Plant program is based on long term objectives and availability of resources as well as infrastructure for their self-dependence and energy security for long term and efficient working (Bajaj et al., 2006). An in-depth study is always required to be done to avoid any possibilities of accidents related to nuclear hazard. Though, the occurrence of accidents has a very low probability, but still they do have consequences on nuclear fuel degradation. Hence there is a need for the safety analysis of IPHWR in case of LOCA.
Numerical investigation has been carried out to study about the temperature distribution of the reactor channel under LOCA with fuel rods deformed and undeformed under high temperature heat transfer. The numerical work of simulation would be done in commercial CFD software ANSYS 14.0.
Nuclear Power comes from the process of splitting Uranium Atoms (also called fission), which in turn releases copious amounts of energy in the form of heat. When the atoms are arranged in a reactor, the splitting of an atom will cause nearby atoms to split, forming a chain reaction. As the energy is released, it is sent through coolant tanks full of water, which is then heated into steam. The steam is channeled and used to spin a turbine, which in turn powers a generator,
Nuclear power has always been a controversial issue because of its inherent danger and the amount of waste that the plants produce. Once considered a relatively safe form for generating energy, nuclear power has caused more problems than it has solved. While it has reduced the amount of traditional natural resources (fossil fuels), used to generate power like coal, wood, and oil, nuclear generating plants have become anachronisms. Maintaining them and keeping them safe has become a problem of immense proportion. As the plants age and other technology becomes available, what to do with these “eyesores” is a consuming issue for many government agencies and environmental groups. No one knows what to do about the problem and in many areas of the world, another nuclear meltdown is an accident waiting to happen. Despite a vast array of safety measures, a break in reactor pipe or a leak in a containment vessel, could spell another environmental disaster for the world.
Nuclear power has no place in having a safe, clean, sustainable future. Today, the manufacturing of nuclear power plants has become a critical topic throughout the world that many strongly believe should be stopped. Nuclear Power is not safe anywhere in the world nor is it environmentally friendly. Nuclear power plants are truly something that could cause mass destruction in the world and has the potential to wipe out a whole country with ease. Despite proponents’ that claim that nuclear power is safe, there is a history that proves otherwise and marks a number of disasters caused by nuclear power plants.
Convection is a transfer of internal energy into or out of an object by the physical movement of a surrounding fluid that transfers the internal energy along with its mass. According to Oxford Dictionary, convection is the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder or denser material to sink under gravity's influence, that results in transfer of heat. Two fluids are liquid and gas.The fluid above a hot surface expands, becomes less dense, and rises.This applies to objects such as steam from a hot cup of coffee turning cool, ice melting like heat moving to ice from the air, or frozen material becoming raw like how frozen food thaws more quickly under cold running water. When
In this experiment the bacteria E. Coli will be genetically transformed into a competent by going through a process called Heat shock. Heat shock is when you take a bacterial cell and have sudden increase in temperature which increases the permeability of the plasma membrane this causes the cell to take up the DNA from the surrounding medium. (Lab Manual) There are several other methods of genetic transformation but in this lab those will not matter. In this specific experiment pGLO will be the medium around the E. Coli. Genetic transformation is the active up take of foreign DNA in a bacterial cell. (PubMed) For genetic transformation to occur we have to have a medium that contains a different DNA than the thing we are trying to genetically transform. The medium in this experiment will be the plasmid pGLO. This pGLO plasmid is a vector, which transfers a gene from one organism to another. (Lab Manual) The plasmid contains the GFP (green fluorescent protein) gene which makes the bacteria glow in the presence of a sugar called arabinose. The pGLO also contains a gene for resistance to the antibiotic ampicillin. Ampicillin will be used to see if the bacteria lived because the ampicillin is an
This chain reaction produces massive amounts of heat. Nuclear reactors take advantage of this heat by pumping water into the reactor, which in turn produces steam. The steam then becomes pressurized through a pipeline and exits into a turbine (“How to do Nuclear”). The pressurized steam causes the turbine blades to spin, producing power which is linked to a generator for use in the main power lines. When the steam passes the turbine blades, it goes past cooled pipes and condensates (“How to do Nuclear”).
Nuclear energy is capable of producing mass amounts of clean energy, but how? Nuclear reactors function similarly to a typical power plant in which heat converts water into steam that in the end turns a generator, producing electricity. However, in the common power plant, heat is
The process of conduction between a solid surface and a moving liquid or gas is called convection. The motion of the fluid may be natural or forced. If a liquid or gas is heated, its mass per unit volume generally decreases. If the liquid or gas is in a gravitational field, the hotter, lighter fluid rises while the colder, heavier fluid sinks. For example, when water in a pan is heated from below on my stove, the liquid closest to the bottom expands and its density decreases. The hot water as a result rises to the top and some of the cooler fluid descends toward the bottom, thus setting up a circulatory motion. This is also why the heating of a room by a radiator depends less on radiation than on natural convection currents, the hot air rising upward along the wall and cooler air coming back to the radiator from the side of the bottom. Because of the tendencies of hot air to rise and of cool air to sink, radiators are positioned near the floor and air-conditioning outlets near the ceiling for maximum efficiency.
The term Nuclear Reactor means an interaction between two or more Nuclei, Nuclear Particles, or Radiation, possibly causing transformation of the nuclear type; includes, for example, fission, capture, elastic container. Reactor means the core and its immediate container. Nuclear Reactors are used to produce electricity . The numbers of Nuclear Reactor plants have grown sufficiently . Electricity is being generated in a number of ways, it can be generated by using Thermal Power. It can be employed by using two basic systems a Steam Supply System and an Electricity Generating System these two systems are related to each other. The Steam Supply System produces steam from boiling water by the burning of coals and the Electricity Generating System produces electricity by steam turning turbines. The Nuclear power plants of this century depend on a particular type of Nuclear Reaction, Fission (The splitting of a heavy nucleus like the uranium atom to form two lighter "fission ! fragments" as well as less massive particles as the Neutrons). In the Nuclear Reactors this splitting is induced by the interaction of a neutron with a fissionable nucleus. Under suitable conditions, a "chain" reaction of fission in which events may be sustained. The energy released from the fission reactions provide heat, part of which is ultimately converted into electricity. In the present day Nuclear power plants, this heat is removed from the Nuclear fuel by water that is pumped past rods containing fuel. The basic feature of the nuclear reactor is the release of a large amount of energy from each fission event that occurs in the nuclear reactors core. On the average, a fission event releases about 200 million electron volts of energy. a typical chemical reaction, on the other hand releases about one electron volt. The difference, roughly a factor of 100 million electron volts. The complete fission of one pound of uranium would release roughly the same amount of energy as the combination of 6000 barrels of oil or 1000 tons of high quality oil. The reactor cooling fluid serves a dual purpose. Its most urgent function is to remove from the core the heat that results when the energy released from the Nuclear reactions is transformed by the collisions into the random nuclear motion. An associated function is to transfer this heat into an outside core, typically for the production of electricity. The designer provides for a nuclear core in a container through which a cooling fluid is pumped.
There are two main types of nuclear reactors used in the world, Pressurized Water Reactors, known as PWR’s, and Boiling Water Reactors, known as BWR’s. The former is more complicated and thusly more safe and more commonly used, while the latter presents several unnecessary hazards and is quickly being phased out of usage (Duke, n.d.). In both systems, reactions take place inside of a reaction chamber located within a co...
The greatest disadvantages of nuclear energy are the risks posed to mankind and the environment by radioactive materials. ‘On average a nuclear plant annually generates 20 metric tons of used nuclear fuel cla...
Literature Review: In order to arrive at a comprehensive understanding of heat stress it is required that we review the science behind the reaction of body to thermal stress, the various methods for measurement of stress and various methodologies used to mitigate this problem.
As discussed in class, submission of your solutions to this exam will indicate that you have not communicated with others concerning this exam. You may use reference texts and other information at your disposal. Do all problems separately on clean white standard 8.5” X 11” photocopier paper (no notebook paper or scratch paper). Write on only one side of the paper (I don’t do double sided). Staple the entire solution set in the upper left hand corner (no binders or clips). Don’t turn in pages where you have scratched out or erased excessively, re-write the pages cleanly and neatly. All problems are equally weighted. Assume we are working with “normal” pressures and temperatures with ideal gases unless noted otherwise. Make sure you list all assumptions that you use (symmetry, isotropy, binomial expansion, etc.).
Nuclear power, the use of exothermic nuclear processes to produce an enormous amount of electricity and heat for domestic, medical, military and industrial purposes i.e. “By the end of 2012 2346.3 kilowatt hours (KWh) of electricity was generated by nuclear reactors around the world” (International atomic energy agency Vienna, 2013, p.13). However, with that been said it is evident that the process of generating electricity from a nuclear reactor has numerous health and environmental safety issues.
A Heat Exchanger is a device use for the heat transfer from one fluid to another, whether the fluids are separated by a solid wall so that they never mix or the fluids are directly in contact. The heat exchanger is widely used in different industries such as process, petroleum refining, chemicals and paper, power generation, chemical processing, A.C, refrigeration, and a food processing applications. Etc. Various Enhancement methods are used to increase performance of heat exchanger such as treated surfaces, rough surfaces etc.