³Ô¹ÏÍøÕ¾

Bushfires are a natural part of life in Australia.

But when fire weather becomes dangerous,

They can threaten homes, lives and livelihoods.

At CSIRO, we’ve studied bushfire behavior for decades to assist fire authorities to better prepare for and respond to bushfire threats.

With climate change increasing, bushfire risks to people and the environment, this research has never been more important, but it’s also extremely difficult.

Changing conditions in the field makes it difficult to obtain detailed measurements, and the mechanisms that drive bushfires.

So, we built a world-class laboratory at the Black Mountain site of Australia’s ³Ô¹ÏÍøÕ¾ Science agency.

It’s home to two unique apparatus. The Pyrotron and the Vertical Wind Tunnel.

These tools allow us to investigate the effect of real-world conditions on fire behavior from wind speed to fuels and all the physics in between, in a safe and repeatable manner.

The Pyrotron is an aluminum, steel, fireproof combustion wind tunnel with a large glass observation area.

At one end isa large fan that provides the wind.The tunnel removes most of the turbulence so that the air that reaches the fire is consistent.

The fuel bed is where we conduct our experimental fires.We usenatural bushfire fuels such as forest leaves, twigs, and bark.00:01:26 Speaker 1But we can also use other fields such as pine needles, grasses or shrubs.

Because the width of the fuel bed is a keyfactor in thespread of bushfire, we know thatour results must be tested in the field at the scale bushfires occur.

Next to the Pyrotron, we have the Vertical Wind Tunnel. This tunnel allows us to investigate the aerodynamic and combustion characteristics of bits of burning bark and debris called firebrands.

In a real bushfire, firebrands are the primary cause of spot fires.The working section allows us to observe a firebrand at its terminal velocity, the speed that that fire brand rises and falls.

It’s terminal velocity will determine how high a firebrand maybe lofted,and how farit will travel.

As the firebrand burns, it will lose mass and its terminal velocity will decrease, meaning it will travel a greater distance from the original fire.

However, we know that the firebrandwill only start a spot fire if it completes its journey while it’s still alight.

Determining the maximum distance it can travel and remain alight is critical to knowing how fast spot fires could go during bushfire.

Both the Pyrotron and the Vertical Wind Tunnel give us glimpses into the mechanisms by which one of our most dangerous natural phenomena propagates.

The research conducted in this laboratory will help firefighters better understand, predict, and combat real bushfires.