Electric field-induced flame convection in the absence of gravity

Abstract

Although chemical fuels uniquely provide a safe way of carrying large amounts of energy within a small mass and volume, their combustion in the absence of gravity raises major problems. Whenever flames are used for heating specific objects under gravity and in an oxygen-containing atmosphere, we rely on natural or forced convection to replenish reactants and direct the hot products. Forced convection requires a compressor or keeping fuel under pressure in cylinders, and thus entails a considerable weight penalty. Natural convection is not available under micro-gravity conditions, making heat transfer from flames difficult to achieve. Indeed, diffusion flames will tend to become spherical and will eventually extinguish as a result of blanketing by their own products. We report here an alternative method of controlling flames in zero gravity based on the application of electric fields, which can be achieved using compact, lightweight equipment.