Unlike the other current ACME experiments, the Burning Rate Emulator (BRE) experiment is focused on fire prevention, especially in spacecraft. Specifically, BRE’s objective is to improve our fundamental understanding of materials flammability, such as ignition and extinction behavior, and assess the relevance of existing flammability test methods for low and partial-gravity environments. The burning of solid and liquid fuels will be simulated by using a flat porous burner fed with gaseous fuel. The fuel flow rate will be controlled based on the measured heat flux (at the burner) and surface temperature, mimicking the dependence of condensed-phase fuel vaporization on thermal feedback. A small number of gaseous fuels will be used to simulate the burning of fuels such as paper, plastic, and alcohol by matching properties such as the surface temperature and smoke production.
International Space Station Ops Images
Example Feb. 2019 flame from the Burning Rate Emulator (BRE) investigation of microgravity material flammability in a quiescent (i.e., no breeze) atmosphere. The fuel is ethylene (C2H4), although it was sometimes diluted with nitrogen. Various atmospheres were used, with oxygen concentrations up to 40% (by volume) and reduced pressures with conditions similar to those being considered for future human space exploration. The burner is 25 mm in diameter. This dynamic image is from shortly after ignition, where the soot can be seen escaping the flame forming the appearance of a crown. But the flame quickly became blue and presumably too cool to generate soot.Astronaut David Saint-Jacques of the Canadian Space Agency is inside the U.S. Destiny laboratory module working on the Combustion Integrated Rack. Saint-Jacques replaced the fuel flow controller on the chamber insert for the Advanced Combustion via Microgravity Experiments (ACME) project which is a set of six independent studies of gaseous flames. The fuel flow controller was replaced to support ongoing testing for ACME’s Burning Rate Emulator (BRE) investigation.Example 2019 flame from the Burning Rate Emulator (BRE) investigation of microgravity material flammability in a quiescent (i.e., no breeze) atmosphere. The fuel is ethylene (C2H4), although it was sometimes diluted with nitrogen. Various atmospheres were used, with oxygen concentrations up to 40% (by volume) and reduced pressures with conditions similar to those being considered for future human space exploration. The burner is 25 mm in diameter.
