Laser Initiated Ignition of Liquid Propellant
Abstract
The 4th Interim Report included the first high speed movie sequence, albeit of rather optical quality, of the interaction between laser generated plasma and a droplet. This was a first step in a more extensive series of studies. Figure 1 shows three sequences illustrating the various parameters under investigations. These include the energy of the laser beam and the distance between the position of the laser focus and the droplet. Moreover, double firing the laser can be used to inject a second plasma kernel into the environment of a drop that is already disintegrating. The records show interaction with the propellant droplet of a rapidly expanding shock wave as well as the more slowly developing plasma kernel and illustrate the wide variation in the rate and completeness of the burning of the droplet that can be achieved. The provisional interpretation is that the shock wave emanating from the laser-generated plasma shatters the droplet and the fine filaments of liquid propellant which result are ignited when they become engulfed by the plasma. This makes the intensity of burning very dependent on the relative positioning of the droplet and laser focus. A second laser pulse (e.g. 200us, 3rd sequence) interacting with the disintegrating and burning fragments from the first in an additional means of promoting rapid decomposition. Comparative experiments with water droplets show shattering without combustion. Keywords: Propellants; Laser ignition.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 1989
- Accession Number
- ADA212342
Entities
People
- F. B. Carleton
- F. J. Weinberg
- K. Krallis
Organizations
- Imperial College London