CFD Benchmarking and Validation has been confirmed (and reconfirmed at TOTeM 30, which will shortly be featured on the IFRF website) as a key area in which the IFRF could be of assistance to Members.  Requests have been received from many quarters for data sets based on both existing and new trial data, on which different modelling approaches could be tested and validated. 

Historically Furnace #1 and the IFRF’s Aerodynamically air-staged burner, AASB have served mathematical modellers requiring validation of their computer codes. The current tests are using FOSPER, the 3-5 MWt replica of Furnace #1 and AASB, which has been rebuilt and will be fired at 2.0MWt.  A programme has been defined which will provide the required data on coal flames in air and oxy-combustion conditions. 

The AASB was selected because its performance characteristics have been studied in detail in an extensive scaling programme conducted by the IFRF in the past.  This burner is specifically designed to use a swirling combustion air stream which undergoes a defined flow transition (vortex breakdown) within the burner quarl.  The vortex breakdown can result in the formation of an internal recirculation zone (IRZ) whose characteristics are critically influenced by swirl generator type, swirl level and burner geometry.

In last week’s tests, the velocity profile was measured inside the furnace. (See graph below).  This week, the investigators are measuring the temperature and chemical compostion profiles inside the furnace.  In parallel, the IFRF’s measurement capabilities are being restored through a process of building and testing the majority of the IFRF-designed probes used in the last decades around the world.

 AASB burner with modified air input

2 MWt Gas flames from the AASB burner

Sample of axial velocity profile