Effect of Inlet Boundary Layer Suction on Flow Distortion in Subsonic Diffusing S-Duct

Characterization of a Low Profile, Rapidly Deployable, MEMS Pressure Sensor Array for Aerodynamic Applications.

“…The L/D ratio of the S-duct is 5 and the diffusion area ratio of A throat /A exit is 0.8. The duct was connected to two straight sections, one at the inlet and other at the outlet, that help with the development of the boundary layer at the inlet and to align the flow to the engine axis at the exit [9,10]. The exit of the duct was connected to a 50 JM Maxfan 2-stage axial fan with dynamic speed control.…”

Automotive Aerodynamics Sensing Using Low-Profile Pressure Sensor Strip

“…Therefore, the S-duct has a total of 48 Scanivalve sensors. The duct both ends were connected to a straight section (inlet and outlet) to help developing the boundary layer at the inlet and to align the flow to the fan at the exit [19], [20]. The exit of the duct was connected to a 2-stage axial fan to control the flow velocity (18, 22 and 27 m/s).…”

S-duct flow distortion with non-uniform inlet conditions

“…Rein and Koch 48 demonstrated that the distortion at the AIP increases proportionally with the thickness of the inlet boundary layer. Thick boundary layers were found to reduce also the pressure recovery on the intake 49 – 51 and to promote non-uniform radial pressure loading on the compressor blades which could trigger stall inception. 4 Different azimuthal orientations of the approaching boundary layer were also investigated for intakes under yaw and pitch angles 52 , 53 , 18 were found to notably influence the fan-face pressure and swirl distortion.…”