Opening pressure of a round primary air nozzle

摘要

In fluidized bed boilers the primary air is blown from the bottom of the boiler. If the nozzles are above the bottom, they are affected by the temperature of the fluid and the erosion caused by the fluid. When the nozzles are placed below the bottom of the boiler their life time is longer. In this case the nozzles are full of sand when the boiler is not in use and when starting up the nozzles have to be opened. In this study the opening pressure of a round nozzle is modelled. The modelling was based on measurements and two different modelling methods were used. First, a regression model was fitted on the data and secondly, a non-linear neural network model was built.