On the ellipsoid itself, where ^ = ^^ , using the value of g„, ip = 0, q>- = 0, hence 



q = ^q I , and, after combining terms. 



9o^ 



1-p.^ 



Co + l\<o + f^' 



-e^g^V 



yc2-e2^2 



[138f 



from Equations [138y, z] and Equation [138d]. 



A circular disk is obtained again by setting e = 1, ^q= 0. Then on the disk q = |g | 

 where ^-^--equals + q and is again given by Equation [138n']. In steady motion the excess 

 of pressure at points on the disk above that at infinity is 



?'-/'o.=^p(^'-?')=-^pf^' 



1- 



[I38u 



Thus p = p^ at w" = 0.844 c. 



Streamlines selected to be equidistant at infinity are shown in Figure 235 for an el- 

 lipsoid with Cq = 0.577, e = 0.866, g^ = 1.628, and for a disk in Figure 236. For the ellips- 

 oid, /) - p^ is shown on an arbitrary scale; it vanishes at fx = 0.68, is = 0.73 c. Values of 

 V ~ V^ ^re shown along the a:-axis and along the ellipsoid, also, plotted horizontally, along 

 the oT-axis above the ellipsoid. 



Figure 235 - Streamlines for flow past an oblate spheroid in the direction of its axis 

 of symmetry. The distribution of pressure p is shown along the axis, then over 

 the spheroid, and outward along a transverse axis. See Section 138, Case 2. 



363 



