Self-Similar Intermediate Structures in Turbulent Boundary L(10)

Self-Similar Intermediate Structures in Turbulent Boundary Layers At Large Reynolds Numbers

4Theremaininggroupofzero-pressure-gradientbound-

arylayerexperiments

Inthissectiontheresultsoftheprocessingarepresentedforalltheremainingseriesofexperiments.ForallofthemweusedthedatapresentedintheformofgraphsinthereviewofFernholzandFinley(1996).TheresultsoftheprocessingarepresentedinTable3andinFigures9–15.

Allthedatarevealtheself-similarstructureinthe rstintermediateregionadjacenttotheviscoussublayer.ThescalinglawsobtainedforthisregiongivevaluesoflnRe1andlnRe2,closetoeachother,althoughthedi erencebetweenlnRe1andlnRe2issometimeslargerthanintheexperimentsofthe rstgroup.Thescalinglaw(5)iscon rmedbyalltheseexperiments.Atthesametime,forthisgroupofexperimentsthesecondself-similarstructureadjacenttothefreestreamturnsouttobelessclear-cut,ifitisthereatall.Therefore,forthisgroupofexperiments,wedidnotpresenttheestimatesforthevaluesofβ.Neverthelesswenotethatwhenitwaspossibletoobtainestimatesofβtheyalwaysgaveaβlessthan0.2.Notealsothatforalltheseexperimentsthenumberofexperimentalpointsbelongingtotheregionadjacenttothefreestreamwaslessthanfortheexperimentsofthe rstgroup:thiswasanadditionalargumentforourreluctancetoshowherethesecondself-similarlayer.AsexplainedinSection3,wesuggestthattheturbulenceoftheexternal owintheexperimentsofthisremaininggroupwasmoresigni cant.