Foundations of Circulation Control Based Small-Scale Unmanned Aircraft by Konstantinos Kanistras Kimon P. Valavanis & Matthew J. Rutherford

Author:Konstantinos Kanistras, Kimon P. Valavanis & Matthew J. Rutherford
Language: eng
Format: epub
Publisher: Springer International Publishing, Cham

Konstantinos Kanistras (Corresponding author)

Email: [email protected]

Kimon P. Valavanis

Email: [email protected]

Matthew J. Rutherford

Email: [email protected]

Observation is a passive science, experimentation an active science

—Claud Bernard

Low Reynolds numbers (Re2.2 10) wind tunnel tests are conducted and the results are presented here. Based on the wind tunnel specifications and the focus on small-scale platforms, 2-D and 3-D wind tunnel tests are conducted based on the assumption that most of the platforms at that scale operate at the same Reynolds numbers. The platform, which is described in Sect. 9.​1, is chosen because of the fact that the average speed that operates is the speed that the wind tunnel wing models are tested.

The experimental results of all CCWs are presented, compared, and discussed. The effect of blowing on lift and drag coefficients is presented along with the improved lift-to-drag ratios. Lift augmentation ratio results are shown and a comparison between all surfaces tested show that CC works at all configurations and with upper slot blowing, lift enhancement is achieved. The qualified wing configuration (NACA 0015 CCW) is tested (2-D wind tunnel test) with two dual radius flap configurations and the results are presented next.

Before moving on to the analysis of the results, it is important to understand the level of uncertainty of the measurements and the parameters that may not be controllable during a wind tunnel test. A block diagram representation of a wind tunnel experiment is shown in Fig. 8.1. The inputs can be parameters that define the experiment as: angle of attack of the wing, roll, pitch, yaw, etc. and in general the initial conditions that are set. Elements that are controlled and defined by the researcher are the: model size, tunnel size, model material, and time of the experiment. The elements of the output vector are the parameters that need to be investigated and are defined by the experiment and are known a-priori. Those elements can be forces, moments components as indicated by the balance, pressure readings, video image, or smoke visualization methods, etc. At last, uncontrollable factors include variables as turbulence level of incoming stream, temperature, relative humidity, model deformation, etc. Even though in principle a parameter should be controllable, it may be uncontrollable. Barlow et al. [63] state that the scope of the parameters that are controllable depends on the resources available to the experiment planner.

Fig. 8.1Conceptual model of an experimental setup, schematic inspired by [63]

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.