Starflight
Well-Known Member
Not sure if it has been posted; NACA TN1945 available from their
technical reports server, has info on 15 different laminar and turbulent
sections at R=700,000 and up. It was published as a guide for G/A
manufacturers in 1949 and seems to have been completely forgotten
in subsequent articles on aerodynamics. I came across it as a subnote
in a textbook written by W.H. Riegels (1951).
Anyone else noticed how the 'dirty-lift and drag' curves of moderate
thickness "6" series laminar sections are superior to those of the
turbulent airfoils?...contradicts the traditional myths of older being
better, so often quoted. Is the linear chord-wise dimension of the
first 10% of the nose covered by roughness responsible for the
difference?...the blunter turbulent airfoils having larger diameter nose
radii (more circumference).
technical reports server, has info on 15 different laminar and turbulent
sections at R=700,000 and up. It was published as a guide for G/A
manufacturers in 1949 and seems to have been completely forgotten
in subsequent articles on aerodynamics. I came across it as a subnote
in a textbook written by W.H. Riegels (1951).
Anyone else noticed how the 'dirty-lift and drag' curves of moderate
thickness "6" series laminar sections are superior to those of the
turbulent airfoils?...contradicts the traditional myths of older being
better, so often quoted. Is the linear chord-wise dimension of the
first 10% of the nose covered by roughness responsible for the
difference?...the blunter turbulent airfoils having larger diameter nose
radii (more circumference).
