Population and sample burned area analyses for near limit flames in a simulated low gravity environment over thin cellulosic fuels.

摘要

The National Aeronautical and Space Administration (NASA) Glenn Research Center in Cleveland, Ohio, has been conducting combustion research in a microgravity environment in order to increase space mission fire safety. The research program ATHINA (Analysis of Thermodiffusive and Hydrodynamic Instabilities in Near-extinction Atmospheres) was a flight definition project related to that mission. Before this research program was to be sent to the International Space Station (ISS) for further work ATHINA had to meet specific scientific requirements. To fulfill the requirements, many earth bound experiments were conducted in the NASA microgravity facilities (Drop Towers) and the MSU microgravity simulator called the SMFT. The results of these experiments were studied in this thesis.;The experimental flamelet study conducted at MSU produced results similar to and compatible with the NASA facility. Flamelet propagation on a cellulosic fuel sample is a form of fuel rich combustion. Flamelets propagate at a nearly constant rate over the sample. The flamelet spread rate is proportional to the velocity of the oxygen supply. To reach a steady state (a condition when flamelet continues to propagate indefinitely) it is required that at least half of the total flamelet population be "productive". The flamelet population study included the development of a computer program to simulate the cumulative population of flamelets using biological population measures and the logistic model.