• Version
• 119 Downloads
• 699.94 KB File Size
• 1 File Count
• April 3, 2017 Create Date
• April 3, 2017 Last Updated

Wind Tunnel Investigation of Control Surface Characteristics - X - A 30% Chord Plain Flap with Straight Contour on the NACA 0015 Airfoil

Force-test measurements in two~dimensional flow have.5 I
been made in the NAOA 4n by 6-foot vertical tunnel to de~"“‘
termine the characteristics of an NACA 0015 airfoil equipped
with a straight~contour plain flap having a chord 30 percent
of the airfoil chord. The straight—contour plain flap dif-i
fare from an ordinary plain flap in that the surfaces be-
hind the hinge axis are flat instead of conforming to the
basic airfoil contour. The results are presented in the
form- of aerodynamic section characteristics for several flap
deflections and for a se sled and unsealed gap at the flap
nose. ,

The slope of the lift curve of the NACA 0015 airfoil-
with 'the straight—contour plain flap was greater than for
the same airfoil with an airfoil~contour plain flap of the
same chord. The effectiveness of the straight—contour flap
in producing increments of lift was slightly less with gap
at the flap nose sealed and slightly greater with gap
unsealed than the corresponding Values for the airfoil»
contour flap, For the straight~contour flap. the variation
of the flap hinge moment with angle of attack and with flap
deflection was larger than for the airfoil-contour flap.

' The straight~oontour flap had apprbximately the same profile-
"drag characteristics as the airfoil«contour flap.-

" =Inmaonpcriow y
, The NAGA has instituted an extensive investigation of
» the aerodynamic characteristics of various flap arrange-

ments in an effort to determine -the types best suited for
‘control surfaces and to supply experimental dat'a for.

___,_1‘ ‘—-‘
_" . p-u-Va.‘ -w..
design purposes. The results of this investigation that
relate to the present report are given in reference 1 and
in the reports listed in the bibliography.

This paper presents the aerodynamic characteristics
of an NAOE 0015 airfoil with a plain flap having a chord
30 percent of the airfoil chord (0.500) and a straight
contour from the flap nose radius to the trailing edge.
The aerodynamic characteristics of the NACA 0015 airfoil
with the "straightecontour flap“ are compared with the
aerodynamic characteristics, given in reference 1, of the
same airfoil with a 0.30c plain flap having an airfoil
contour from the flap nose radius to the trailing edge.
This plain flap of reference 1 will be referred to in
this report as the “airfoi1~contour flap.“