Document G6ywmZRRgZrYg1jDOXMKxpVan

AMERICAN SOCIETYOF BEATM & VENTILAim EN6INEERS6DIDE.I923 than two-thirds than that of the latter, and there is no inverted cone at the top to direct the flow of the exhaust outward. Further the outlet openings, as shown in Fig. 79, are small as compared with those of Fig. 76. The poorest ventilator is the stationary siphon, Figs. 75 and 80. This ventilator is so designed that the outside air enters the head; the head is small, the band is narrow and the air passages leading from the ventilators are restricted. The rotary ventilator shown in Fig. 64 has a low efficiency for this class of ventilators, due to the fact that the head is small and the air passages are restricted by louvers and frame work. The data obtained in a series of tests on 10-in. ventilators made at Kansas State Agricultural College by Professors J. P. Calderwood, A. J. Mack and C. J. Bradley and reported in the American Society of Heating and Ventilating Engineers Journal, July, 1922, are shown in Tables 62 to 66 inclusive, and the average resultsof Table 66 are shown in curve sheet, Fig. 82. TABLE 62. RESULTSOF TESTS SHOWING THE VELOCITY IN FEET PER MINUTE INDUCED THROUGH SEVEN DIFFERENT PLAIN STATIONARY VENTILATORS Vei.. of AVind in Miles per Hr. Velocity Induced Through Ventilator. Feet per Minute Ventilator Designation No. Ventilator 1 2 3 4 5 6 7 4 145 185 266 148 185 142 133 160 8 241 287 355 257 '287 238 242 267 12 337 390 446 366 390 334 350 375 TABLE 63. RESULTS OF TESTS SHOWING THE VELOCITY IN FEET PER MINUTE INDUCED THROUGH SIX STATIONARY SIPHONING VENTILATORS MILES per Hr. Velocity Induced Through Ventilator, Feet per Minute Ventilator Designation No. Ventilator 1 2 3 4 5 6 4 145 162 157 226 189 205 206 8 241 304 292 404 315 332 369 12 337 446 426 583 440 458 532 TA BLE 64. RESULTS OF TESTS SHOWING THE VELOCITY IN FEET PER MINUTE INDUCED THROUGH FOUR PLAIN ROTARY VENTILATORS Vel. of Wind in Miles per Hr. Velocity Induced Through Ventilator. Feet per Minute Ventilator Designation No. Ventilator 234 4 145 208 192 _ 191 202 8 241 246 348 ' 354 341 12 337 484 505 518 480 145