The Study of Initial Flow Characteristics for Al-gelled Propellants
- Paper number
IAC-09.C4.8.12
- Author
Mr. Taehoon Kwon, Hanwha Corporation, Korea, Republic of
- Coauthor
Mr. Taeho Rho, Hanwha Corporation, Korea, Republic of
- Year
2009
- Abstract
Nowadays, the demands of propellant systems which have high energy density, improved safety and easy to handle characteristics have been increasing in the space launch propulsion systems. The slurry propellant system had been regarded as one of the promising propellant systems to answer that demands and therefore many researchers had studied the slurry systems. But, regardless of their advantage of high energy density, the slurry propellant systems which contain the solid particles in liquid have serious problem of solid particle sedimentation by gravity in storage condition and acceleration in flight condition. Because of this problem, the slurry systems have not been applied to propulsion systems yet.1) The promising alternative system is solid added gel propellant system. The advantage of gel propellant's safety, application flexibility and energetic performance, in comparison to liquid and solid propellants, have led to increased study in propulsion systems. Gel propellans are non-Newtonian fluids and their rheological behavior are generally shear thinning and thixotropic characteristics.2) The non-Newtonian behavior of gel propellants lead to many problems with feeding and atomization systems. Especially, the one of the key points in lightweight and efficient gel propulsion systems is reducing initial force for flow from stationary to moving gel. This study is tested for obtaining the bases of effective gel propulsion systems. The initial flow properties of gel propellant propulsion system such as driving force and delay time for required mass flow etc. was studied with solid particle added gel propellant simulant. The gel propellant simulant is made with organic gellant in water and is prepared to be rheologically similar to the gel propellant. The test equipment throws gel propellant simulant through nozzle for hydraulic actuator. Hydraulic actuator genarated initial driving force and stroke with stall power - 3,307kgf, max unloading velocity - 216.7mm/s and max stroke ±35.0mm. This Study reviews the relation of driving power and stroke that test equipment measured driving force with a combined tension and compression loadcell of 7,500lbs range, stroke with LVDT(Linear Variable Displacement Transformer). High speed camera taked a picture of gel propellant simulant jet at nozzle end. This test acquired the syncronous data of driving force, stroke and gel propellant simulant jet. References 1. "Combustion Related Aspects of Gel Fuels", Benveniste Natsn(Faculty of Aerospace Engineering, Technion - Israel Institute of Technology), 3rd European Combustion Meeting ECM 2007 2. "On Shear Rheology of Gel Propellants", Shai Rahimi, Arie Peretz(RAFAEL, MANOR Propulsion and Explosive Systems Division, P.O.Box 2250(M1), Haifa 31021(Israel) Benveniste Natan(Faculty of Aerospace Engineering, Technion-Israel Institute of Technology, Haofa 32000(Israel), Propellants, Explosives, Pyrotechnics 32, No.2(2007)
- Abstract document
- Manuscript document
(absent)