Samanta, RatnadeepRatnadeepSamantaRowthu, SriharithaSriharithaRowthu2025-10-212025-10-212026-02-0110.1016/j.ces.2025.1227432-s2.0-105017972412http://repository.iitgn.ac.in/handle/IITG2025/33293Lubricant infused slippery surfaces are vulnerable to external shear flow of fluids (water, air). This study reports the influence of mimicked commode flushing turbulent (Re ∼ 6129) water flow on the silicone oil retention and feces self-cleaning properties in microgrooved polydimethylsiloxane replicas fabricated using banana leaf template. Oil retention amounts are 28 %, 42 %, and 24 % for 20 min of constant turbulent flow in parallel (∥), perpendicular (⊥) directions to grooves and on untextured surfaces, respectively. Post flow, water slide-off angles (SAs) are ∼ 9° for ⊥ flow, ∼14° for ∥ flow, showcasing the retention of slipperiness. On the other hand, untextured surfaces lost their slipperiness. Also, oil retention in air under 200 gliding water droplets shows trend of ⊥ to grooves > ∥ to grooves > untextured. Furthermore, oil coated microgrooves displayed smaller coefficient of friction of 0.35 ± 0.009 (⊥ to grooves), 0.38 ± 0.003 (∥ to grooves), as compared to untextured surfaces (1.73 ± 0.198), when abraded with a steel ball in reciprocating motion using 1 N load, 40 mm⋅s⁻¹ sliding speed and 10 mm sliding distance. After 30 consecutive cycles of synthetic feces deposition, its residual amount is lowest when sliding on ∥ to grooves as compared to ⊥ to grooves and untextured surfaces. Clearly, a trade-off between ⊥ and ∥ directions to grooves can provide optimal oil retention and self-cleaning properties in sanitation and sewage systems.falseAnisotropic slippery surfaces | Drop shedding | Feces repellency | Friction coefficient | Self-cleaning | Shear drainageArticle1 February 20260122743