Study on Flow Characteristics of Stirring S-type Blades in Microgravity Environment

The adaptability of microorganisms in microgravity environments has been largely validated through space station launches. As a key core equipment in microbial cultivation devices, the flow field characteristics of agitators are crucial for the safe survival of microorganisms. This article selects a microbial cultivation device and its stirrer as the research object. Detailed analysis of the internal flow field morphology of the mixer and the distribution of stagnation zones. The key parameters involved in optimizing the flow field and their influencing laws were provided through numerical analysis. Result shows that the maximum internal shear stress does not exceed 2Pa, which is much lower than the limit that the algal cell wall can withstand. The stagnant area of the internal flow field of a single S-shaped blade is relatively large, which may cause local algae to die due to hypoxia. By reducing the value of r, the proportion of stagnant areas can be effectively reduced. Double S-shaped blades can greatly improve the internal flow morphology and reduce the proportion of stagnant areas.