Design Fire?

XPRIZE

As we continue designing this prize and particularly flesh out all the different testing we need to do, it becomes increasingly important for us to finalize the design of the test fire.

In other words, what are the different characteristics that define the fire we will seek to target with this prize? We have some preliminary characteristics we are thinking of, based on feedback received so far—variables that correspond to fires specifically in Southern California. Please see below and weigh in! Is this the right design fire to be thinking of as we flesh out our testing? Are we missing any key variables? Should the variables be set at some other threshold? Why or why not?

• Fuel: Chaparral
• Fuel Moisture: at the very least <50%, preferably <30%
• Humidity: <15%
• Terrain: Steep, there should be a ridge (and valley). (We were warned by many not to start the fire at the bottom of a slope).
• Wind: 30-50 miles per hour (for outdoor testing, lab testing will be at higher winds)

Thank you for your thoughts!

NickAzer

Please share any thoughts, examples, or links you might have!

Eti

Hello everyone,
Since posting this question, we were advised to consider a different fuel. While here at XPRIZE we work to push innovation as far as we can, in consideration of the generally extreme fire conditions we look to have, Chapparal - may pose too much risk. As such, we began looking into Fuel Model 2 - a combination of Timber and Grass. More details about the fuel model are here: https://gacc.nifc.gov/rmcc/predictive/Fire Behavior Fuel Model Descriptions.pdf

akb

Any successful solution, almost by definition, should be able to tackle any type of fire (any fuel, any location, in any weather conditions). So testing should replicate this requirement - though adequate safety precautions must be taken in advance [consult fire safety experts, and prepare the land for realistic and safe test scenarios].

As mentioned elsewhere for this challenge, some testing might be conducted indoors or in a lab, if the risks are judged to be too high in an outdoor environment.

This suggests some aspects to include in testing:
Being dense, impenetrable, and prone to infrequent, large, high-intensity wildfires is the natural condition of chaparral."

akb

Testing the ability of equipment to reach the site is also relevant to the overall challenge; including the quantity of extinguishing material (e.g. water) that the solution might rely on.

Almog

I agree with @akb comment that any solution should be able to tackle any type of fire, any location in any weather conditions. Just the amount of water differs from one scenario to another. I'd recommend to implement 2 key OUTDOOR scenarios:
1. Medium case scenario: Fuel model 2 (4 tone of fuel per acre, flame length of 6 feet).
2. Worst case scenario: Fuel model 4 (13 tone of fuel per acre, flame length of 19 feet).

Other variables mentioned by @XPRIZE above could work perfect. From safety reason and total cost, I tend to feel that the test field should be limited of some sort. Let's say, 300m over 300 m.

akb

That sounds good @Almog particularly the worst case scenario.

@everyone
Some solutions in the challenge might adopt low water usage alternatives or solutions without the use of water. (radical innovation :-)

DanSelz

Hi @Almog , interested to know more about why you feel the test field should be limited to such a relatively small size. We have gotten feedback that the test size should be quite large, to challenge the ability of teams to pick out a small fire in a very large area. Thanks!

Almog

Following @DanSelz question about the test field size. My appology, it's going to be a bit long.

I think we should start with the critical problem we want to solve. I'd have thought that appropriate operational goal is to save lives (in small isolated towns, urban interface, etc.) AND critical property of some sort (energy site, hospitals, etc.). The challenge of achieving that, for my view, is blocking the fire front which threats those places ONLY, creating safe zone for presence of people in it. I've analysed a lot of real scenarios and have found that in average, only fire line 100-500 meter long is relevant to focus on. The rest of multiple fire fronts spread with absolutely no threat on human life.It would be waste of resources to chase those fires.

For an example, large wildfire could spread let's say over 1.5 mill. acres. Within that area we should be able to creat 1-3 separate safe zones (1-3 diferent sites) where we sould block 300 meter of fire front each, for 10 hours (day and night) AND, knocking down hundres of unexpected small hot spots (caused by flying emebers) before they join together. This is quite similar to the defence plan of firefighting forces. To gather the forces in preplanned critical sites. Any of innovative solution should do it 5-10 min after alarm is turn on, wherever it's needed in that area (1.5 mill. acres).

Therefore, I think a typical test field size could be 200 over 200 square meter. It's quite sufficient to demonstrate the required operational capability, as if in real life we need to scale up only the number of this "test field areas".

Another way to look at it is defining large area of test field (full with vegetation) contains Area Of Interest (AOI) of 200 X 200 m2. The innovative solutions will be tested in AOI only.

Does it make sense?