Boiler Construction

We are designing a software tool that will allow Nalco Fuel Tech engineers to easily construct virtual representations of several different types of commercial boilers and incinerators.

To simplify construction of the virtual boilers, we have defined features commonly found in boiler construction, such as waterwalls, superheaters, and ash hoppers, as fundamental objects in the software. For a full graphical representation, several attributes are associated with each fundamental object. For example, an exterior wall is fully defined by the $n$ vertices in space defining its polygonal shape, a texture image, its position, and orientation and by a Boolean boundary attribute. By using this approach, a new virtual boiler unit can easily be constructed in less than a day.

The two figures above show typical external views of a generic tire incinerator unit. The view on the left shows a side view of the unit, including several headers (the long gray pipes along the sides and top) and the chute in which pulverized tire particles are dropped into the combustion chamber. The figure on the right shows the top of the incinerator unit where pipes from the water walls containing steam and water meet at the center header. From this point, steam is piped through superheater structures within the boiler and to become supersaturated, while the water is recirculated through the walls of the unit.

The two figures above show internal views of the tire incinerator unit discussed previously. Most walls of the incinerator are lined with pipes that circulate water and steam through the unit (and hence are known as water walls). These pipes are automatically calculated for each polygonal wall by simply assigning a piping attribute to the wall in the data input file. The figure on the left shows the view from the combustion chamber of the incinerator looking up into the first passage for the flue gases. The picture on the right shows our representation of the injectors used in the Nalco Fuel Tech NOxOUT process to reduce nitrogen oxide emmissions into the atmosphere.

It is critical that the user have access to every compartment of the boiler to study all aspects of the velocity flow field and temperature distribution. Navigation through the boiler compartments is achieved by using the wand to control two different modes of movement: a flight simulator mode, which allows the user an arbitrary orientation, or jet pack mode, which maintains a vertical orientation of the user's head. The display frame rate associated with navigation through the boiler is increased by using several optimization techniques including clipping planes, interior/exterior spatial definitions, customized graphics objects, and display lists.