Laminar flow drop tube furnace

In order to obtain detailed information on the evolution of fuel nitrogen, a laminar flow drop tube furnace, able to simulate conditions found in actual combustion systems, was adopted for this study. 

The experimental furnace is a vertically oriented laminar flow drop tube furnace having a 30 cm long uniformly hot test section with optical access. The fuel droplet array is introduced on the logitudinal axis concurrently with the ambient gas. The droplet stream is interrupted at several points in its trajectory by a sampling probe inserted axially from the base of the furnace. The probe quenches and transports the entire flow to a sampling train which recovers the fuel droplet residue for analysis. The above process is repeated at several furnace temperatures for each fuel. A detailed description of the system is to be found in references (3) and (4). 

The primary research tools used in this program were C-E s Drop Tube Furnace System (DTFS), a bench scale entrained laminar flow furnace and the Controlled Mixing History Furnace (CMHF), a pilot scale entrained plug flow furnace. Both the DTFS and CMHF by virtue of their ability to resolve combustion time into distance along their respective furnace lengths were used to examine carbon burnout phenomena associated with the SRC and reference coals. In addition, the CMHF by virtue of its staged combustion capabilities was used extensively to evaluate N0X emissions and to establish conditions conducive to low N0X ... 

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