To evaluate the effect of a converging injector geometry, volumetric flow rate and gallant content on the pressure drop, the velocity and viscosity fields, the governing equations of the steady, incompressible, isothermal, laminar flow of a Power-Law, shear-thinning gel propellant in a converging injector were formulated, discretized and solved. A SIMPLEC numerical algorithm was applied for the solution of the flow field. The results indicate that the mean apparent viscosity decreases with increasing the volumetric flow rate and increasing the gallant content results in an increase in the viscosity. The results indicate also that the convergence angle can produce additional decrease in the mean apparent viscosity of the fluid. The mean apparent viscosity decreases significantly with increasing the convergence angle of the injector, and its value is limited by the Newtonian viscosity η∞. The effect of the convergence angle on the mean apparent viscosity is more significant than the effect of the volumetric flow rate and the gallant content on the mean apparent viscosity. Additional decreasing the viscosity results in increasing the pressure drop with increasing convergence angle. It is important to injector design that the viscosity decreasing and the pressure drop increasing are took into account together.

To evaluate an influence of the various bend diameter ratio Rc/R and velocity on the flow property of gel propellant in a 900pipe bend, the 3D governing equations of the steady, incompressible, isothermal, laminar flow of a power-law, shear-thinning gel propellant in pipe bend were formulated, discretized and solved, a SIMPLEC numerical algorithm was applied for the solution of the flow field, which on a series of sharp 900curved pipelines with nine kinds of bend diameter ratio and the inner diameters of 8mm were used on condition of seven kinds of Reynolds numbers. The pressure and velocity distributions were obtained, the empirical equation of local resistance coefficient from numerical experiments was conducted, providing the interrelations between the best bend diameter ratio and flow velocity in engineering design. The results indicate that the pressure and velocity distributions were non-linear, and which become tremendous with increasing Reynolds numbers. The results suggest that the dot of maximum velocity occurs the wall outside of a pipe bend, and which is more near to the wall outside of a pipe bend along the flowing direction and increasing the velocity. The phenomena of particle sedimentation should be took into account to investigate the flowing behavior of gel propellant in curved pipes on condition of lower Reynolds numbers.

To describe detailedly the flowing process and field of gel propellants in the round pipe, the experiments of the gel flowing in the tubes were conducted and the governing equations of the steady, incompressible, isothermal, laminar flow of a power-law, shear-thinning gel propellants in 3D pipe were formulated, discretized and solved. The results indicate that pressure drop per unit length increases with decreasing the tube diameter as well as increasing the mass flow rate, and the liquidity of gel is more difficultly than water, and the wall-slip effect of the tube flowing for gel propellants must be considered. The results indicate also that the velocity increases as the flow moves downstream as well as with decreasing the tube diameter, and the apparent viscosity decreases as the flow moves downstream, and the apparent viscosity on the radial center is the maximum. For the same tube geometry, the apparent viscosity at the exit plane decreases with increasing the mass flow rate. For the same tube length and the same mass flow rate, increasing the tube diameter results in an increase of the apparent viscosity at the exit plane.

The numerical simulation, based on computational fluid dynamics methodology, has been performed to study the two-phase turbulent combustion flow in rocket engine using non-metallized multicomponent propellant. A reduced reaction mechanism is developed for modelling combustion of fuel droplets in the absence of metal. Gas governing equations are two dimensional axisymmetric N-S equations in Eulerian coordinates. The trajectory model is adopted to analyse the droplet-phase including the droplet collision, breakup and evaporation. The gas flow is influenced by the droplets by adding source term to N-S equations. The reliability of the simulation programme is validated by comparing numerical simulation result with engine test data.