The thick steel vessel is to contain the high pressure of the water in the reactor, the concrete is to provide radiation shielding, for the operating crew mainly but also to prevent outside equipment from becoming irradiated
The pressure vessel contains the reactor core with its fuel, coolant, moderator, control elements, and emergency systems. The turbine is the device that on receiving the steam it spins and turns the electric generators to produce electricity.
For the PWR, the reactor core which is an array of fuel assemblies, inside a very strong pressure vessel made of thick steel. The top of the vessel is removable for fuelling, and also holds the control rods and their mechanisms. The whole thing is enclosed in a secondary containment. Also inside this is the primary circuit which circulates water through the core to carry away the heat produced by the fuel assemblies, and the secondary circuit steam raising units which send steam to the turbine. See link below
The reactor itself does not make a lot of sound when operating. Nuclear fission is silent, but moving water in the core (in a pressurized water reactor) might be heard as it circulates. But it would not be easy to put your ear to the reactor vessel as radiation levels would be very high and the vessel would be very hot. Certainly the pumps that are running to circulate coolant will be audible.
The first line of shielding is to limit the neutron bombardment of the pressure vessel, to give it a safe life of 40 or more years. Then you need to protect personnel who have to go into areas close to the reactor for maintenance, and also to limit the exposure of equipment which may need maintanance done during the life of the plant
The way a nuclear reactor works is by producing heat which produces steam turning turbines and producing electricity, it does this by using a process called fission. The fuel rods produce neutrons which speed off into another fuel rod spliting the atoms inside(U-235) which then produces more neutrons and so on so fourth, this process produces heat which is used to make steam that drives turbines producing electricity for the masses.
A nuclear reactor is surrounded by several layers of physical barriers designed to contain and shield the reactor core. These layers typically include a reactor pressure vessel, a primary containment structure, and secondary containment buildings made of materials like steel and concrete to prevent the release of radioactive materials in case of an accident.
The reactor vessel is the main container that houses the nuclear fuel, control rods, and coolant in a nuclear reactor. Its purpose is to contain and shield the nuclear reactions happening inside, and to provide structural support and safety for the reactor core.
for pressurized light water reactor type, as an example, the nuclear reactor components are * Reactor vessel (that contains the nuclear fuel and surrounded with water and contains control rod for power control and for safety) * reactor coolant pump * steam generator * reactor pressurizer * piping out of the vessel to the pressurizer, from pressurizer to steam generator, from steam generator to reactor coolant pump, and from pump back to the reactor vessel.
The pressure vessel of a nuclear reactor contains the reactor core and helps to maintain a high pressure environment to prevent coolant water from boiling. It also serves as a barrier to contain radioactive materials and provide structural support for the reactor.
Nuclear fission takes place in the nuclear fuel rods that are placed in the reactor core that is situated in the reactor pressure vessel. The reactor pressure vessel is usually situated inside the reactor containment.
A steam turbine/generating unit, or a naval vessel
The pressure vessel contains the reactor core with its fuel, coolant, moderator, control elements, and emergency systems. The turbine is the device that on receiving the steam it spins and turns the electric generators to produce electricity.
to control the radiation
In the most severe reactor accident, the fuel will melt and, due to radioactive decay heat, will continue to be very hot. In fact, it will be hot enough to melt through the bottom of the reactor pressure vessel (several inches of steel), and possibly melt/burn through the concrete floor of the reactor building and get into the soil beneath the building. This is what is referred to as the China syndrome, the idea being that the molten mass of fuel is heading toward China on the other side of the earth as it melts through the vessel, concrete, and then soil and rock below the reactor building.
A reactor vessel in a boiling water reactor is approximately 300 tons.
The nuclear reactor of a nuclear power plant is usually considered to be the core and the pressure vessel in which it is encased. The control rods, which are in the core (and pulled some or all of the way out to run the reactor) have their associated rod drive motors on top of the pressure vessel. Instrumentation ports are up there, too. All of these things are generally considered to be the "nuclear reactor" portion of the primary system in the plant. A link is provided to a picture posted at Wikipedia. It has a portion of it colored to show the reactor core, but the pressure vessel is "cut away" to view the core. The control rods (#1 in the drawing) are shown as being on top. That's incorrect. The rod drive motors and control rod lead ("leed" and not "led") screws are up there. (The lead screws connect the control rods, which are down in among the fuel bundles, to the rod drive motors, which are up on top of the pressure vessel's cap.) The rods belong in the core, or in the area above the core when they are pulled out. The whole thing, the core, the vessel, and the rod drive motors as well as the instrumentation on top are considered to be the "nuclear reactor" in a power plant. If asked to identify the picture, the most correct response is probably, "It's a cut-away drawing of a nuclear reactor." That means everything in the picture is part of the nuclear reactor.
The part of a nuclear power plant that undergoes a fission reaction is called the reactor core. This is where the nuclear fuel, such as uranium or plutonium, is housed and where the chain reaction occurs to produce heat energy.