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Evaluation of low-gravity smoke particulate for spacecraft fire detection
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Yang, Jiann Urban, David Ruff, Gary A. Cleary Sr., Thomas Bryg, Victoria Yuan, Zeng guang Meyer, Marit Greenberg, Paul |
| Copyright Year | 2013 |
| Description | Tests were conducted on the International Space Station to evaluate the smoke particulate size from materials and conditions that are typical of those expected in spacecraft fires. Five different materials representative of those found in spacecraft (Teflon, Kapton, cotton, silicone rubber and Pyrell) were heated to temperatures below the ignition point with conditions controlled to provide repeatable sample surface temperatures and air flow. The air flow past the sample during the heating period ranged from quiescent to 8 cm/s. The effective transport time to the measurement instruments was varied from 11 to 800 seconds to simulate different smoke transport conditions in spacecraft. The resultant aerosol was evaluated by three instruments which measured different moments of the particle size distribution. These moment diagnostics were used to determine the particle number concentration (zeroth moment), the diameter concentration (first moment), and the mass concentration (third moment). These statistics were combined to determine the diameter of average mass and the count mean diameter and by assuming a log-normal distribution, the geometric mean diameter and the geometric standard deviations were also calculated. Smoke particle samples were collected on TEM grids using a thermal precipitator for post flight analysis. The TEM grids were analyzed to determine the particle morphology and shape parameters. The different materials produced particles with significantly different morphologies. Overall the majority of the average smoke particle sizes were found to be in the 200 to 400 nanometer range with the quiescent cases and the cases with increased transport time typically producing with substantially larger particles. The results varied between materials but the smoke particles produced in low gravity were typically twice the size of particles produced in normal gravity. These results can be used to establish design requirements for future spacecraft smoke detectors. |
| File Size | 815116 |
| Page Count | 13 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20140006579 |
| Archival Resource Key | ark:/13960/t07x1cr3h |
| Language | English |
| Publisher Date | 2013-05-19 |
| Access Restriction | Open |
| Subject Keyword | Fire Safety Smoke Fire Soot Spaceborne Experiments Particulates Smoke Detectors Air Flow International Space Station Particle Size Distribution Transmission Electron Microscopy Fires Aerosols Mulholland George Microgravity Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
