Preliminary Analysis of the CO2 Fire Suppressant Distribution System for Space Station Freedom 911473

To date, the fire suppression capabilities resident on United States spacecraft have been somewhat limited and highly crew dependent. The spectrum of previous suppression systems extends from the food rehydration water on Mercury and Gemini to the Halon distribution system and portable extinguishers flown on the Orbiter and Spacelab. The challenge presented by Space Station Freedom of assuring crew safety while maintaining a permanent manned presence in space has led to the design of a more extensive fire suppression distribution system. This is the first time that carbon dioxide will be used as the suppressant. This choice partially overcomes present problems of post-fire toxic substance cleanup and monitoring of two phase Halon quantities in microgravity. During the development and testing activities surrounding this system, analyses have been performed to predict system conditions such as suppressant discharge flow rates, suppressant state, and dilution times. These preliminary results can provide a basis for estimating the capability of the baseline design to meet the WP01 derived system requirements.