Wood burner flue NOx emissions

A few months ago, Dr Amanda Lea-Langton of The University of Manchester kindly invited me to visit their Sustainable Energy Research Facilities to measure the transient NO and NO₂ from a 5 kW domestic wood burning stove.

A CLD50 was fitted to the flue at the position shown in the photo above where the gauge pressure was measured at 12 Pa.

The test set-up and running conditions were:

4 paraffin firelighters of 10 g each were positioned at each corner of a 400 g pile of dry ash wood kindling and lit with the door open (without any bottom draught).

Firelighters were lit at Time = 0 s with the door ajar until T = 240 s when the door was closed.

Two 750 g construction pine logs were added at T = 330 s (involving door opening and closing).

At T = 1,800 s, the door was opened, logs were poked and door closed again.

The resulting NO & NO₂ data as measured in the flue are shown below:

This video shows rolling data beside the flame state showing the undulations in NO associated with flame movement:

There are some nice transient features associated with operating a wood burning fire and presumably similar for other gases too (HC, CO & CO₂). 

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Previous work undertaken by Cambustion recording particle size and number using a DMS500 is shown here.