Nuclear Power Plant Applet Description

Henrik Eriksson
Dept. of Computer and Information Science
Linköping University
S-581 83 Linköping, Sweden

Power Plant Model

This applet provides a (very rough) simulation of a nuclear power plant. This power plant consists of three major components: the reactor, turbine, and condenser. Furthermore, there are three pumps, four valves, and one turbine. The reactor boils the water and the steam generated drives the turbine. After the turbine, the condenser cools the steam. In turn, external cooling water cools the condenser. The cooling pumps transport the water from the condenser tank back to the reactor tank.

The simulator calculates values for reactor-tank pressure, condenser-tank pressure, water levels, and so on, and displays them graphically. When components fail, the simulator calculates and displays the consequences for the running power-plant system. For instance, if a cooling pump fails and the corresponding valve is not closed, water may flow backwards from the reactor tank to the condenser tank. This process will then drain the reactor tank and expose the reactor core.

User Interaction

The user can start several simulation sequences where components of the power plant fail. In Sequence 1, the turbine fails, and the state of the power plant changes accordingly. In Sequences 2 and 3, cooling water pump 1 fails, and the external-cooling water pump fails, respectively. (You may have to resize the browser window to see the external-cooling water pump, because it is located to the left of the condenser.) The randomize button invokes a sequence where two random components fail. For instance, the turbine may fail and then a few seconds later a cooling pump may fail.

The simulator allows user interaction with certain components when a simulation sequence is running. The user can open and close valves by clicking on them, and can start and stop pumps by clicking on them. Moreover, the user can change the position of the moderator rods by dragging them with the mouse. The simulator disables user interaction with components immediately after a sequence is completed.

Applet Description

The applet implementation consists of two major parts: (1) the graphical user interface and (2) the power-plant simulator. In the version of the applet you seen on the demonstration WWW page, the simulator component is implemented in Java-compatible and run together with the graphical-user interface in your Java browser (e.g., HotJava and Netscape 2.0). Although this Java-based simulator is now running locally in you browser, it can be configured to communicate with a remote simulator server that receives user input and transmits simulation output data to the browser client (through a TCP/IP stream).