Saffire

Problem Identification

Full scale fire testing complemented by computer modeling has substantially improved our understanding of the risk, prevention and suppression of fire in terrestrial systems (cars, ships, planes, buildings, mines, and tunnels). In comparison, no such testing has been carried out for manned spacecraft due to the complexity, cost and risk associated with operating a material flammability experiment of a relevant size and duration in microgravity. Therefore, there is currently a gap in knowledge of fire behavior in spacecraft.

 
 
 NASA Test1 challenges
 Flammability limits differ

 

Vehicle Configuration

CygnusCygnus

Cygnus approaching the ISS

Cygnus

Cygnus interior Cygnus in Shroud

 

Overpressure Testing and Modeling

The experiment will need to meet rigorous safety requirements to ensure the carrier vehicle does not sustain damage.

Overpressure TestingOverpressure Testing Overpressure Testing Overpressure Testing

 

Experiment Configuration

Experiment Configuration
 Experiment Configuration
Experiment Installed in Cygnus
Thrust vector aligned with x-axis
Foam on both sides and bottom of Saffire
 Experiment Configuration
Sample card with 5 cm by 30 cm samples

Cutaway view of the flow duct and avionics enclosure

 



Sample Selection

Sample 3

 Structured Samples

 Sample 2

Flame spread over thin combustible layer with high heat conductivity inclusions

Sample 3
Sample 4
 Streamlines
 Flame velocity versus flow velocity

 

The Road Ahead

The large-scale material flammability demonstration will facilitate the understanding of the long-term consequences of a potential spacecraft fire and provide data not only for the verification of detailed numerical models of such an event, but also for the development of predictive models that can assist and optimise fire prevention, response and mitigation.

The first step is to provide an predictive tools that will integrate fire safety into design and management of space vehicles. Such tools will integrate a wide range of design issues including, but not limited to, material selection, emergency response, crew training, post-fire clean-up, fire detection, fire suppression, environmental control and life support (ECLS) system design, and even atmosphere selection to provide a globally optimised solution.

Contact David Urban and / or Grunde Jomaas for more information or to express interest in participation.