Sessile drop creation in weightlessness is critical for designing scientific instruments for space applications and for manipulating organic or biological liquids, such as whole human blood or DNA drops. It requires perfect control of injection, spreading, and wetting; however, the simple act of creating a drop on a substrate is more complex than it appears. A new macroscopic model is derived to better understand this related behavior. We find that, for a given set of substrate, liquid, and surrounding gas properties, when the ratio of surface free energies to contact line free energy is on the macroscopic scale, the macroscopic contact angle can vary at static equilibrium over a broad volume range. It can increase or decrease against volume depending on the sign of this ratio up to an asymptotic value. Consequently, our model aims to explore configurations that challenge the faithful representativity of the classical Young’s equation and extends the present understanding of wetting.

在失重状态下产生静滴对于设计用于空间应用的科学仪器和操纵有机或生物液体（如全人类血液或 DNA 滴）至关重要。它需要对注射、铺展和润湿进行完美的控制；然而，在基板上创建液滴的简单操作比看起来更复杂。推导出一个新的宏观模型以更好地理解这种相关行为。我们发现，对于一组给定的底物、液体和周围气体特性，当表面自由能与接触线自由能的比率处于宏观尺度时，宏观接触角可以在很宽的体积范围内在静态平衡下变化. 它可以随体积增加或减少，具体取决于该比率的符号直至渐近值。最后，