Boundary Lyer Theory

524 XVII. Origin of turb~~lrnce 11 f. Shbility of a boundary layer in the presence of thrco-dimensional disturbancra 525
'l'hc rcsult~s of an investigation by 13. R. van lhicst and J. C. Boison [34] on a
conr at Me = 1 .!I, 2.7 and 3.7 arc shown in Fig. 17.31. Thc increase in the transition
Itrynoltls nrlml)or 1vit.h cooling is clcarly seen, as is the reduction of thc st,:~bilizat~ion
ofloot. wiL11 increasing Mar11 number. 'l'lic Int.t,cr trend continues to llighcr Mach numhrs,
n.s mn,s shown by 1.h~ small stal)ilizat~ion cffcct found on flat platcs at M, = 6.0
ant1 6.5, respccl,ivcly, I)y A. M. Gary (211 and 1). V. Maildalon ( 1561. These cffccts of
w~olilrg arr in c:oml)lc*t,c. acrortl with t,hr I~cllnvioirr of first-mode tlist,nrl~ances
shown
ill It'ig. 17.27. Ilowt:vcr, in lwo cxpc~ritncnki by N.S. I)i:r.conis, tJ.lt. .Jack and It..l.
\\'islli(~\vski 147, 101 J, at. M, = 3.12, cooling Iwyontl the rcgion of st,al~ilizat,ion shown
in Fig. 17.31 rrsnlt.crl in a tlecrrosc rat-ller 1.han an increase in the t,ransit,ion Reynolds
nn1111~t~. This pl~enon~enon has bccn rallctl "l.ransit,ion reversal" because it is contmry
1.0 1.11~ cxprct,cd t.rcn11. It 1la.s :dso INWI OI~SCI~VC(I in sI~o(:Ic tunnrls by I$. E.
Itic:ll:~rtls nnd ,J. 1,. Stoilcry 1195, 1961 011 a flat, at. M, = 8.2, and by K. F.
Fig. 17.31? Expcrinrcntnl tmtisilion dn1.a ohtnirrcd
on a iOo-cone at. zero angle of incidcncc showing
~tnbilizing cffcct of wall cooling nt three
Mnrh nunrhers in a sr~personic wind trinnel, nftm
15. I