Leading-edge nose droop suppresses cloud cavitation through pressure recovery reorganization and confined vapor-liquid shear layer momentum exchange

Cloud cavitation is governed by pressure recovery and vapor-liquid shear layer instability. How leading-edge nose droop modifies this coupled process to suppress cloud shedding remains unclear. Large-eddy simulations are performed to examine how parameterized nose droop affects pressure redistribution, near-wall flow response, and cloud shedding. The deformation region ratio and nose-drop ratio are used to control the streamwise extent and amplitude of the local geometric modification. In non-cavitating flow, nose droop weakens the suction peak, increases near-wall shear, and delays chordwise boundary layer development. Under cavitating conditions, moderate deformation ( x ₀/C = 0.4, d ₀/ x ₀ = 0.1) reorganizes pressure recovery: a near-zero pressure gradient plateau appears around mid chord, confining adverse gradients to a narrow closure region. This pressure redistribution is accompanied by a shift of the vapor-liquid shear layer from strong off-wall exchange to weak near-wall confinement. The Reynolds shear stress peak moves from y /C ≈ 0.025 for the baseline to y /C < 0.01, indicating a more wall-attached shear layer state. The cycle-averaged cavity volume drops from 0.219 to 0.002, corresponding to a reduction above 99%, and sustained organized cloud shedding is largely suppressed. Excessive nose droop moves the closure downstream, where adverse gradients and localized unsteadiness reappear, indicating a finite effective deformation window. These results suggest that cloud cavitation suppression is associated with confined adverse pressure gradients, weakened off-wall shear layer exchange, and reduced turbulent momentum transport toward the cavity closure.