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 … Read the rest ⇢
- The Advanced Combustion via Microgravity Experiments (ACME) project includes six independent experiments investigating laminar gaseous non-premixed flames. In other words, the flow is smooth and without vortices, the fuel is a gas (and not a liquid or solid), and the fuel and oxygen are not mixed in the burner (but are instead on opposite sides of the flame sheet).
- ACME is focused on advanced combustion technology via fundamental microgravity research. The primary goal is to improve efficiency and reduce pollutant emission in practical terrestrial combustion, for example through the development and verification of improved computational models. A secondary objective is fire prevention, especially for spacecraft.
- In addition to enhanced performance, the improved modeling capability resulting from ACME could lead to reductions in the time and cost for combustor design.
- Some specific ACME goals are to improve our understanding of combustion at fuel lean conditions where both optimum performance and low emissions can be achieved, soot control and reduction, oxygen-enriched combustion which could enable practical carbon sequestration, flame stability and extinction limits, and the use of electric fields for combustion control.
- The goal of ACME’s spacecraft fire prevention research is to improve our fundamental understanding of materials flammability, such as extinction behavior and the conditions needed for sustained combustion, and to assess the relevance of existing flammability test methods for the screening and selection of materials for spacecraft.
Research, especially including that already conducted in microgravity, has revealed that our current predictive ability is significantly lacking for flames at the extremes of fuel dilution, namely for sooty pure-fuel flames and dilute flames that are near extinction. The general goal of the Coflow Laminar Diffusion Flame (CLD Flame) experiment is to extend the range … Read the rest ⇢
Cool diffusion flames were discovered during droplet combustion experiments aboard the International Space Station (ISS) in 2012, and this initiated a rapidly growing field of combustion research. Droplet experiments necessarily involve unsteady burning rates, so cool diffusion flames have never been observed as steady spherical flames. A natural progression toward understanding cool diffusion flames is … Read the rest ⇢
Electric fields can strongly influence flames because of its effect on the ions present as a result of the combustion reactions. The direct ion transport and the induced ion wind can modify the flame shape, alter the soot or flammability limits, direct heat transfer, and reduce pollutant emission. The purpose of the Electric-Field Effects on … Read the rest ⇢
The primary goal of the Flame Design experiment is to improve our understanding of soot inception and control in order to enable the optimization of oxygen enriched combustion and the “design” of non-premixed flames that are both robust and soot free. An outside review panel recently declared that Flame Design “… could lead to greatly … Read the rest ⇢
Results from the Structure and Response of Spherical Diffusion Flames (s-Flame) Experiment on the International Space Station (ISS) The s-Flame Experiment science team (Princeton U., Rutgers U., and Glenn Research Center) completed the second and final round of tests in July. Those tests, conducted as part of the Advanced Combustion via Microgravity Experiments Project, featured … Read the rest ⇢