Experimental Assessment of the Sprayed Liquid Flap

The spray liquid flap (SLF) is a novel powered lift concept and is composed of an atomized spray ejected from the pressure side of a lifting body. The SLF relies on a two-way-coupled interaction between the liquid and the freestream flow to modify the aerodynamics of the adjacent lifting body. This paper aims to assess the aerodynamics of SLFs experimentally to provide evidence supporting previous numerical findings and to provide a dataset for future validation efforts. The experimental efforts include a low-aspect-ratio wing fitted with a sprayed liquid flap system. The wing is fitted with a load cell to measure loads and with high-speed imagery to provide physical insight. We utilize a two-way-coupled, Euler–Lagrangian approach to directly recreate the experiment. Our findings indicate that the CFD model matches experimental force and surface pressure measurements. The CFD model is then adapted to represent a two-dimensional flow—these results are used to describe the physics of the SLF.