Pressure around Sj)heres in a Viscous Fluid. -431 



The pressure-curves plotted from the readings for normal 

 pressure '2'S mm. are given by the full-line curve nim^ 

 fig. 11. The pressure-distribution around sphere A is 

 quite similar to the pressure-distribution around a single 

 sphere. The pressure-distribution around sphere B differs 

 from that of a single sphere owing to the proximity of 

 sphere A. 



7. 2^he Pressure Distribution around two Spheres loliose 

 Line of Centres is Perpendicidar to the Stream-lines. — Two 

 glass spheres of five millimetres diameter were mounted so 

 that their line of centres was perpendicular to the direction 

 of flow, the distance apart of their surfaces being 2 mm., 

 Plate XYIII. fig. 3. 



As the pressure-distribution around the two spheres is not 

 symmetrical with respect to the horizontal and vertical planes 

 containing the line of centres, the distribution was obtained 

 in these two planes ; the distribution in the horizontal plane 

 is given in Table III. 



Since the distribution of pressure is not symmetrical with 

 respect to any plane, the opening was rotated through 360°, 

 readings being taken for each 10° for the first 90° and for 

 each 30° thereafter. 



Table III. 



Angle y. 



Pressure in mm. 



Angle Q. 



Pressure in mm. 





of water. 





of water. 



o 









o 







l-oO 



120 



005 



10 



1-40 



150 



0-15 



20 



1-20 



180 



0-22 



30 



1-20 



210 



0-15 



40 



1-20 



240 



0-15 



50 



1-05 



270 



005 



60 



0-60 



300 



0-50 



70 



0-30 



330 



1-10 



80 



0-15 



360 



1-50 



90 



0-05 



1 







The distribution of the pressure according to the above data 

 is exhibited in Plate XYIII. fig. 12, curve mm. As the curve 

 about B would be the image of that about A the readings 

 wer(; only taken over A. 



The curves of the distribution of pressure around these 

 spheres differ from the curve around a single sphere in pro- 

 truding slightly at a position between 30° and 60° from the 

 line of centres on the side nearest the companion sphere. 



The curves are plotted to a scale of one centimetre to one 



