444 



HYDRAULICS AND ITS APPLICATIONS 



The above table shows the distribution of energy as obtained in a 

 series of tests on a wheel of which the following are the details l : 



15 ; angle a = 4 41'5'. 



19-5 inches ; angle y = 166. 



252 square inches ; head, 810 feet. 



33'5 inches. 



40-5 



300. 



Nozzle needle nozzle, with tip 7*5 inches diameter. 

 The large value of the bucket losses, particularly in trials 3 and 4, is 

 undoubtedly due partly to the comparatively small ratio of width of 



Number of buckets 

 Width 

 Projected area 

 Radius of pitch circle . 



outside tip of buckets 

 Revolutions per minute . 



FIG. 198. 



bucket to diameter of jet, and partly to the design of bucket, which i 

 shown in Fig. 198. 



The following table, showing results obtained in recent tests of Peltoi 

 wheels, 2 well illustrates the extent to which the high efficiency i 

 maintained at part loads in a well-designed wheel. 



1 "Proceedings Inst. Mechanical Engineers," January, 1910. 



2 By Professor F. Prazil. " Proceeding* Inst. Mechanical Engineers," 1910-11. 



