Pyrotron: A national bushfire research facility

About the Pyrotron facility

This national research facility is building upon CSIRO’s 60 years of experience with large-scale field experiments. It is enhancing research on bushfire behaviour by enabling observations of flame propagation and behaviour not possible in field experiments due to limited burning conditions, lack of access and safety concerns.

The Pyrotron allows us to:

• gain a better understanding of the physical processes involved in the behaviour and spread of bushfires under a range of conditions
• develop better models of fire behaviour to improve effectiveness and safety of fire-fighting
• improve the design and execution of large-scale field experiments
• develop a better understanding of likely emissions from bushfires in different fuel and burning conditions.

The facility enables close observation of combustion mechanisms under repeatable conditions not possible in the field. It is used to study:

• the mechanisms by which bushfires spread
• thermokinetics - the chemistry of combustion in bushfires
• fuel consumption, emissions and residues under different burning conditions.

Features of the Pyrotron

Tunnel

• 25 m long
• 4 m² in cross section
• Constructed of 3 mm aluminium
• Working section constructed of 5 mm aluminium

Wind

• 2 tonne fan capable of moving 22 cubic metres of air a second
• Variable wind speed of up to 5.5 metres per second, equivalent to wind speed of around 60 kilometres per hour in the open

Fuel bed

• 1.5 m wide by 4.8 m long
• Lined with ceramic tiles
• LPG line or ethanol ignition sources
• Toughened-glass viewing doors for observing the fire
• Artificially illuminated, so that the fuel will be visible against the light from flames.
• Holds up to 15 kg of dry fuel spread to around 2 cm deep, being roughly equivalent to an average forest fuel load of 25 tonnes/ha.
• Can accommodate different fuel types, such as small logs, leaves, forest litter or grasses.
• Fuels can be artificially dried to replicate extreme burning conditions associated with wildfires.

Instrumentation and observations

• A wide range of sensors in the working section ensure correct and accurate measurement.
• Data is captured by a multi-channel data acquisition system that provides real-time output of sensors to a multi-display system.
• Multiple high definition video cameras above and from the side of the Pyrotron, a high speed camera capable of shooting HD footage at 1000 frames per second, and a high resolution infra-red thermal imaging camera capture details of combustion.

Other details

• Relies upon ambient temperature and humidity, meaning that experiments can be conducted on days of high heat and low humidity to observe fire behaviour in extreme conditions.
• Experiments last about 15 to 20 minutes and yield about as much smoke as a wood-fired backyard barbecue.