Abstract

Nuclear reactors are boilers. The basic difference between their operation and that of regular boilers is that the heat source in a nuclear reactor is not a fossil fuel that is charged from the outside, but the fuel rods inside the reactor. What makes such a boiler more difficult to operate is that turning off this internal heat source is harder, because stopping the nuclear reaction is more difficult and time consuming than it is to close a fossil fuel feed valve. This being the case and because it is essential to keep the fuel rods covered with cooling water so that they will be protected from overheating and melting, the accurate knowledge of the level of cooling water both inside and outside the core is essential. Yet, in many nuclear power plants around the world, such accurate sensors do not exist.