<DOC>
<DOCNO>
800
</DOCNO>
<TITLE>
wall interference at transonic speeds on a hemisphere cylinder model .
</TITLE>
<AUTHOR>
rogers, e.w.e. and hall, i.m.
</AUTHOR>
<BIBLIO>
a.r.c., c.p. 510, september 1959 .
</BIBLIO>
<TEXT>
tests have been made in three n.p.l. wind tunnels on a pressure-plotting
 model consisting of a long cylinder with a hemispherical nose . the
surface pressure distributions were measured for stream mach numbers
between 0.7 and 1.1 at zero model incidence, and schlieren photographs
were taken . the blockage ratios were 0.211(, 0.117( and 0.120( .
the principal feature of the flow is the effect of working section size
on the rate at which the terminal shock wave moves back along the model
with increasing stream mach number . this is thought to depend mainly
on the distance from the model to the slotted walls of the tunnel,
and not necessarily on the blockage ratio . the distance of the solid
sidewall is important in influencing the local mach number ahead of the
terminal shock, by reflecting the expansion-wave system originating near
 the model nose .
</TEXT>
</DOC>
