Temperature simulation and experiment of centrifugal mixing process for high viscosity fluid slurry

In the mixing process of solid propellant preparation, centrifugal mixing equipment achieves efficient blending of components through a combined rotational motion of the container's self-rotation and orbital rotation, forming a high-viscosity fluid slurry. To reveal the temperature change patterns dominated by viscous dissipation during mixing, a finite element analysis model was established using ANSYS Fluent, taking tri-component esterified polypropylene glycol (HTPB) propellant as an example. Static temperature was used as the observation index to study the effects of orbital rotation speed N and the ratio i between self-rotation and orbital rotation speeds on propellant temperature. Results show that the temperature of HTPB propellant exhibits a strong linear correlation with mixing time (r²>0.98), which can be effectively characterized by the average temperature rise ΔT over 10 seconds during mixing. Increasing both orbital and self-rotation speeds leads to higher propellant temperatures, with orbital rotation speed having a more significant impact. When i=−1, increasing the orbital speed from 300 r/min to 600 r/min results in a ΔT of approximately 1.89 ℃,significantly higher than the 0.72 ℃ increase caused by the same increment in self-rotation speed (at N = 600 r/min). Propellant temperature is slightly higher under co-directional rotation compared to counter-directional rotation. The minimum simulated temperature rise ΔT occurs at i=−0.5, corresponding to the highest safety level during the mixing process.