Fuel rod nuclear reactor process involves several tablets which are used to produce heat that is majorly as a result of fission (Cengel n.p). The pellets/tablets full of uranium are in small cylinder form measuring about 5m long and 1mm long that are closed on the both ends. They are filled in the rods and the space in between them also filled by a static gas which ensures an effective heat transfer from the pellets to a coolant. Once the reaction is stirred, it is stretched in all the rods thereby producing heat that is spread to the contiguous water.
Looking at the above process, the heat transfer from the rods to the coolant is as a result of conduction and convection coefficients. The pellets produce heat that moves in the rods till they reach the coolant. This involves conduction of heat in the pellets and in the rods and then final convection from the surface of shield that gets to the coolant.
Boiling Water Reactor (BWR) and Pressurized Water reactors (PWR) are light-water nuclear reactors commonly used for the production of electric power with BWR being the major one used worldwide than PWR. The major distinction between BWR and PWR is that BWR reactor core heat water to steam and then this steam is driven into the turbine and power is extracted. In PWR, the reactor core heats water but it do not boil and exchanges heat with lower pressure water systems that change to steam and drives into the turbines as power. Here, the initial water is heated to up to 300C.It then flows to the heat exchanger then transports the heat to secondary water which receives the heat and changes into steam to produce power.
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