Towards Practical Hybrid Laminar Flow Control

Towards Practical Hybrid Laminar Flow Control: Boundary Layer Stability with Suction and Scalability of Pressure Losses across Perforated Sheets

Hemmen, Patrick (TU Delft Aerospace Engineering)

Kotsonis, M. (mentor)
Rius Vidales, A.F. (mentor)
van Oudheusden, B.W. (graduation committee)
Ragni, D. (graduation committee)
Cosin, Renato (graduation committee)

Delft University of Technology

Aerospace Engineering

2018-03-29

Hybrid laminar flow control (HLFC) reduces skin friction drag, by combining boundary layer suction with pressure gradient tailoring to delay boundary layer transition. This research addresses two key developments required to perform the aerodynamic design of suction-type HLFC components. First, an existing numerical transition prediction tool was made compatible with boundary layer suction, by incorporating suction in its boundary layer solver and by ensuring that an appropriate grid of disturbance frequencies is evaluated with linear stability theory. Second, the scalability of the pressure losses associated to the perpendicular flow through large-scale and actual-scale perforated sheets was investigated experimentally. This development is required to predict the pressure losses of generic HLFC surfaces. It was found that the scalability of these pressure losses is limited, because the frictional losses inside holes decrease continually with decreasing hole diameter. In contrast, the inertial losses across holes reach a steady value with sufficiently many holes.

hybrid laminar flow control
HLFC
suction
stability
pressure loss
perforated sheet

http://resolver.tudelft.nl/uuid:c9492ef8-9254-4ba4-83b3-8b0ad46149c5

Student theses

master thesis

© 2018 Patrick Hemmen