Investigation of the Dynamic Behavior of UDMH Gel Fuel to Select a Suitable Simulant and Rheological Model

Gel propellants are the optimal state of liquid propellants. Gel propellants not only have the advantages of liquid and solid propellants, but also don’t have the disadvantages of the mentioned propellants. The rheological properties of these propellants have a great effect on their propulsion systems, especially in the dynamic state. Regarding the fact that missile and rocket propellants are usually toxic and it is very difficult to study their dynamic behavior in the propulsion system, in this study to select a gel simulant (non-toxic) that can simulate the dynamic behavior of the UDMH gel fuel sample, different gel simulants with methylcellulose, carboxymethyl cellulose and hdyroxypropyl methylcellulose were made and the dynamic behavior of the gel simulants were compared with the dynamic behavior of the UDMH gel fuel. The results showed that the gel simulant made with 0.85% wt. of HPMC gellant is very similar to UDMH gel in terms of dynamic behavior. Also, among rheological models power-law, cross, carreau-bird, and carreau-yasuda, the carreau-yasuda rheological model was able to predict the behavior of the selected gel simulant in a dynamic state in a wide range of the shear rates.