Monopropellant Droplet Decomposition for Large Activation Energies.
Abstract
The quasi-steady decomposition of a monopropellant droplet in a quiescent atmosphere is analyzed for an Arrhenius reaction. An analytical relation is obtained for the pre-exponential rate constant, or the Damkohler number, as a function of the droplet vaporization rate. For low values of the ambient temperature, the curve giving the vaporization rate in terms of the Damkohler number is S shaped and, thus, exhibits ignition-extinction characteristics. The lower bend of the S curve correspond to a nearly frozen regime, under which ignition conditions occur due to the large temperature sensitivity of the reaction rate. The upper bend of the S Curve corresponds to a regime, where nearly complete decomposition of the reactant occurs when it reaches a thin reactive-diffusive zone, after crossing a transport zone. This zone becomes thin, and thus planar, for large Damkohler numbers, resulting in a droplet decomposition rate proportional its radius. For low ambient temperatures a segment of the curve between the two bends of the S curve corresponds to a regime of partial decomposition in a thin reaction zone.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1974
- Accession Number
- ADA010930
Entities
People
- Amable Liñán