THE STATUS OF GEL PROPELLANTS IN YEAR 2000

The present study is a review of the main aspects of gel propellant research and development. The work deals with the following subjects: Historical background of gel propellants; Advantages of gel propellants in comparison to liquid and solid propellants: safety, performance, storage; Theoretical performance evaluation of different gel propellant formulations for various missions; Rheological characterization: definition of the gel type, rheometry, identification of the parameters that affect the rheological properties; Preparation of gel propellants, gellants, compatibility of the ingredients; Flow behavior: power law, shear dunning fluids in pipes and injectors, thixotropic effect; Atomization: investigation of non-Newtonian fluid atomization characteristics, feeding systems; Combustion behavior: non-metallized fuel droplet ignition and burning, metallized fuel combustion and secondary atomization, combustion of gel fuels in small motors.