# Page:EB1911 - Volume 14.djvu/116

104
[TURBINES
HYDRAULICS

sluice successively, any number of sluices can be opened or closed as desired. The turbine is of 48 horse power on 5~12 ft. fall, and the supply of water varies from 35 to 112 cub. ft. per second. The Hence the vane angle at inlet surface is given by the equation cot0 = (wi -V.)/ug = (0-82-0-5)/o~45 = ~71; 0=55°. The relative velocity of the water striking the vane at the inlet

FIG. 200. efficiency in normal working is given as 73 %. The mean diameter of the wheel is 6 ft., and the speed 27-4 revolutions per minute. As an example of a partial admission radial How impulse turbine, a 100 h.p. turbine at Immenstadt may be taken. The fall varies from 538 to 570 ft. The external diameter of the wheel is 4% ft., and

F1o. 201. its internal diameter 3 ft. IO in. Normal speed 400 revs. per minute. Water is discharged into the wheel by a single nozzle, shown in fig. 202 with its regulating apparatus and some of the vanes. The water enters the wheel Y l e enf=;i§ 'ea€:.ii W % A tion of motion, & '® ' Zggle oilithe viiiireiil N § vanesis2o°. The

§ efficiency on trial
' &~ 199. Theory