choked flow of gases
TRANSCRIPT
P.O. BOX Q • TRUMBULL, CT 06611 • CT PHONE (203) 261-6711 • TOLL FREE PHONE (800) 533-3285 • FAX (203) 261-8331
© O'KEEFE CONTROLS CO. • 2000 ALL RIGHTS RESERVED e-mail [email protected] • website www.okcc.com
Choked Flow of Gases
When the air velocity reaches sonic velocity(P2/P1 ≤ .528) further increases in P1 (upstreampressure) do not cause any further increase inthe air velocity through the orifice. Conse-quently it is wrongly concluded that the massflow rate also does not increase.
As the air pressure (P1) increases, the densityof the air also increases; and since the massflow rate is also a function of density, the massflow rate increases linearly with pressure (P1).
Even though the air velocity through the orifice is limitedto the speed of sound, the mass flow rate continues toincrease as the absolute pressure (P1) increases.
What is Choked?The parameter that becomes “choked” or“limited” is the velocity of the air. It is moreaccurate to use the term “choked velocity”rather than “choked flow” when the absolutepressure ratio of air through an orifice is≤ .528.
Vacuum Conditions
Air at atmospheric pressure enters the orifice and flowsto a downstream vacuum pump.
In the case of vacuum conditions on the outletof an orifice and where the inlet is at ambientatmospheric pressure, both the air velocityand the mass flow rate become choked(limited) when sonic velocity is achievedthrough the orifice.
For atmospheric inlet pressure and downstream vacuum,both the air velocity and mass flow rate are limited.
The Basic ConceptA greatly misunderstood and misappliednotion is that of “choked flow”, also referredto as “critical flow”.
In gas flow through an orifice there is an occa-sion where the gas velocity reaches sonicconditions. This occurs for air flow when theabsolute pressure ratio is .528, i.e. when thedownstream absolute pressure (P2) is 52.8%of the upstream absolute pressure (P1).
Sonic velocity occurs for air flow whenP2
/P1 ≤ .528.
The air flow velocity is limited once the absolutepressure ratio is ≤ .528.
For air flow through an orifice with aninlet air temperature of 68oF the choked(sonic) velocity is 1129 ft/sec.
The Misconception!Once sonic velocity is achieved in orifice airflow (P2/P1 = .528), it is easy to "assume" thatthe mass flow rate is constant for all pressureratios less than .528; i.e. P2/P1 ≤ .528. Forexample, when P2 is 14.7 psia and P1
is 27.84psia, sonic velocity occurs through the orifice.As P
1 further increases there is no further
increase in the velocity of the air flowingthrough the orifice.
Conditions for the onset of sonic velocity in orifice air flow.
Consider all the Factors!The mass flow rate through an orifice is a func-tion of three basic parameters.
Q (flow) is a function of• Velocity• Density• Orifice Area
The reason for the mass flow rate limitation isthe fixed inlet density combined with the fixedvelocity. The flow charts on pages 16-18 showthe choked mass flow effect for vacuum con-ditions. At vacuum levels between 15-30” Hgthe mass flow rate is fixed.
Choked Flow for PositivePressure ConditionsAs in the case of the above vacuum conditionsthere are certain situations in which chokedflow does occur for positive (above atmo-spheric) pressure. By maintaining a fixed in-let pressure to the orifice and allowing theoutlet pressure (back pressure) to vary, thereis a range of outlet pressures over which themass flow rate is fixed.
For example (see chart below).
• With an inlet pressure of 80 psig, the massflow rate is choked (limited) for all outletpressures less than 35.30 psig (includingvacuum conditions).
• The actual flow rate is constant for theoutlet pressure range of 35.30 psig to aslow as a complete vacuum. The flow ratecan be obtained from the charts on pages16-18; e.g. for an orifice of .010" diam-eter and with 80 psig inlet pressure, thechoked flow rate is 8.4 scfh (page 16). Thisflow rate will be constant for all outletpressure conditions between 35.30 psigand full vacuum.
0 1 .528
Sonic Velocity
Mass FlowRate
Air Velocity 0➔➔➔➔➔ 0
MassFlow Rate
➔➔➔➔ ➔ AirVelocity
➔➔➔➔ ➔
Sonic Velocity Conditions – Air Flow Outlet PressureInlet Pressure
For Sonic VelocityGage Absolute Absolute Gage
Pressure Pressure Pressure Pressurepsig psia psia psig100 114.7 ≤ 60.56 ≤ 45.8690 104.7 ≤ 55.28 ≤ 40.5880 94.7 ≤ 50.00 ≤ 35.3070 84.7 ≤ 44.72 ≤ 30.0260 74.7 ≤ 39.44 ≤ 24.7450 64.7 ≤ 34.16 ≤ 19.4640 54.7 ≤ 28.88 ≤ 14.1830 44.7 ≤ 23.60 ≤ 8.9020 34.7 ≤ 18.32 ≤ 3.6215 29.7 ≤ 15.68 ≤ .98
14.7 29.4 ≤ 15.52 ≤ .8210 24.7 ≤ 13.08 ≤ -1.625 19.7 ≤ 10.40 ≤ -4.301 15.7 ≤ 8.29 ≤ -6.470 14.7 ≤ 7.76 ≤ -6.94
Temperature 68°F
P2 = 14.7 psia = 0 psig
P2 /P1 – Absolute Pressure Ratio
0 1 .528
Sonic Velocity1129 ft/sec @
68°F
Choked FlowChoked Velocity
MassFlow Rate
➔➔➔➔ ➔
➔➔➔➔➔ 0
P2 /P1 – Absolute Pressure Ratio
AirVelocity
➔➔➔➔ ➔
P1 = 14.7 psia
P2 < P1Vacuum
P1 = 14.7 psia = 0 psig
StandardAtmosphericConditions
P1 = 27.84 psia = 13.14 psig
P2 = 14.7 psia = 0 psig
Sonic VelocityThrough Orifice
TUTORIAL
0 1 .528
Sonic Velocity1129 ft/sec @
68°F
Air velocity isconstant inthis region
AirVelocity
➔➔➔➔ ➔
➔➔➔➔➔ 0
P2 /P1 – Absolute Pressure Ratio
P1 P2
38
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.1
Supply Pressure – psig
Choked Flow
Vacuum LevelIn. Hg. Supply Pressure – psig
Choked Flow
Orif
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Dia
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035
0.03
70.
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0.03
90.
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0.04
10.
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0.04
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0.05
20.
055
0.06
00.
063
0.06
70.
070
0.07
30.
076
0.07
90.
081
0.08
60.
089
0.09
40.
096
0.10
00.
104
0.10
90.
113
0.12
00.
125
Inch
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Siz
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3738
3940
4142
4347
52
55 6
063
6770
7376
7981
8689
9496
100
104
109
113
120
125
Cv
0.02
80.
031
0.0
320.
033
0.03
60.
038
0.03
90.
041
0.04
80.
059
0.06
80.
081
0.08
80.
100.
110.
120.
13 0
.14
0.15
0.17
0.18
0.20
0.21
0.2
3 0
.25
0.27
0.31
0.34
0.37
17.
378.
128.
75 9
.45
9.75
9.90
10.6
11.4
13.6
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725
.930
.133
.635
.939
.343
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.760
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3.7
69.8
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83.9
91.
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110
65
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18.0
19.3
20.6
21.6
22.
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3.9
25.
630
.137
.343
.050
.655
.364
.271
.676
.583
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108
116
131
138
150
162
180
195
216
229
1022
.5 2
5.0
26.5
28.
830
.5 3
1.4
33.1
35.6
41.0
51.9
57.4
68.2
74.6
86.2
96.6
103
112
121
131
144
153
172
181
196
216
237
250
286
314
1527
.830
.732
.635
.437
.538
.640
.543
.250
.062
.969
.782
.690
.310
411
712
513
614
715
817
418
520
721
823
526
1 2
86 3
0334
537
720
32.4
36.0
38.4
41.5
44.3
45.3
47.
750
.9 5
8.7
74.2
82.0
97.3
106
123
138
146
160
172
185
203
216
242
256
275
305
33
535
440
344
525
37.5
41.
544
.147
.9 5
0.9
52.3
54.
958
.5 6
7.6
85.
494
.511
212
214
115
816
818
319
821
223
3 2
48 2
78 2
9231
6 3
4738
140
546
4 5
1130
42.4
47.0
50.0
54.2
57.6
59.3
62.3
66.3
76.3
96.6
107
126
138
160
179
190
206
222
239
265
280
314
331
356
392
432
458
525
578
4052
.558
.167
.267
.071
.273
.376
.982
.094
.311
913
215
617
019
622
023
325
427
329
532
434
338
440
543
9 4
8353
256
6 6
48 7
1450
62.5
69.
173
.779
.785
.087
.591
.797
.511
214
215
718
520
223
326
127
8 3
0132
434
738
440
745
648
152
357
663
467
277
185
060
72.7
80.5
86.
0 9
2.8
9910
210
711
313
016
518
2 2
1423
326
930
132
034
737
540
044
5 4
73 5
3055
960
666
773
578
089
498
570
83.1
91.7
98.
110
611
311
712
212
914
818
720
7 2
44 2
6730
734
336
239
442
845
8 5
09 5
38 6
04 6
3869
3 7
63 8
39 8
9210
2111
2580
9310
311
011
912
713
113
714
516
721
023
1 2
7329
834
338
440
544
348
151
357
0 6
04 6
7871
677
885
694
310
0011
4612
6390
106
115
122
132
141
146
151
161
185
231
256
303
331
379
424
447
489
532
568
631
670
750
792
860
947
1042
1106
1267
1398
100
114
126
135
146
156
164
167
177
203
254
282
331
362
415
468
496
540
587
627
697
739
831
875
951
1047
1153
1225
1403
1545
510
.411
.412
.313
.314
.314
.515
.416
.319
.2 2
3.9
26.4
31.
4 3
6.2
42.4
47.7
50.6
55.
160
.064
.070
.376
.184
.988
.6 9
6.1
104
114
123
138
150
1013
.114
.415
.416
.617
.618
.019
.2 2
0.3
23.6
29.4
32.7
38.6
44.
9 5
1.7
57.6
63.
468
.974
.879
.987
.994
.910
611
012
013
014
215
317
318
715
13.8
15.2
16.2
17.4
18.3
18.8
20.0
21.1
24.
530
.533
.739
.446
.854
.060
.266
.171
.878
.083
.591
.799
.011
011
512
513
514
816
018
019
520
13.8
15.2
16.2
17.4
18.3
18.8
20.0
21.1
24.5
30.5
33.7
39.4
46.8
54.
060
.266
.171
.878
.0 8
3.5
91.7
99.0
110
115
125
135
148
160
180
195
3013
.815
.216
.217
.418
.318
.8 2
0.0
21.1
24.5
30.5
33.7
39.4
46.8
54.0
60.
266
.171
.878
.0 8
3.5
91.
799
.011
011
512
513
514
816
018
019
5
Vacuum LevelIn. Hg.
Sta
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Co
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70
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Orif
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50.
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70.
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90.
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10.
012
0.01
30.
014
0.01
50.
016
0.01
70.
018
0.01
90.
020
0.02
10.
022
0.02
30.
024
0.02
50.
026
0.02
70.
028
0.02
90.
031
0.03
20.
033
Inch
es
Siz
eN
umbe
r4
56
78
910
1112
1314
1516
1718
1920
2122
2324
2526
2728
2931
3233
Cv
0.00
035
0.00
061
0.00
086
0.00
120.
0015
0.00
190.
0025
0.00
280.
0034
0.00
380.
0043
0.00
500.
0055
0.00
670.
0073
0.00
800.
0088
0.00
960.
011
0.01
20.
013
0.01
40.
016
0.01
70.
018
0.01
90.
022
0.02
40.
025
10.
035
0.06
40.
086
0.12
70.
170
0.22
60.
280
0.30
80.
398
0.45
0.52
0.61
0.66
0.77
0.86
0.96
1.05
1.13
1.29
1.41
1.54
1.67
1.91
1.95
2.21
2.39
2.65
2.88
3.03
50.
090.
160.
210.
300.
400.
520.
650.
710.
921.
061.
211.
411.
541.
761.
982.
222.
472.
652.
973.
243.
53 3
.83
4.34
4.44
4.94
5.31
5.86
6.42
6.80
100.
120.
220.
310.
430.
570.
740.
931.
011.
291.
481.
681.
952.
012.
262.
542.
833.
163.
534.
334.
755.
185.
556.
156.
437.
187.
838.
639.
409.
9815
0.16
0.28
0.39
0.54
0.72
0.93
1.17
1.26
1.62
1.85
2.10
2.44
2.50
2.85
3.23
3.57
4.01
4.41
5.35
5.93
6.43
6.95
7.58
7.95
8.78
9.58
10.6
11.6
12.3
200.
190.
330.
460.
650.
851.
101.
381.
491.
922.
192.
492.
872.
973.
403.
864.
264.
845.
226.
356.
957.
588.
158.
909.
2810
.311
.212
.413
.514
.325
0.22
0.39
0.53
0.75
0.98
1.27
1.59
1.71
2.20
2.50
2.86
3.28
3.42
3.92
4.45
4.91
5.59
6.01
7.30
7.95
8.65
9.38
10.2
10.7
11.7
12.8
14.2
15.4
16.3
300.
250.
440.
600.
851.
121.
431.
801.
932.
472.
823.
213.
693.
874.
435.
035.
566.
336.
818.
238.
989.
7510
.611
.512
.013
.214
.415
.917
.318
.440
0.30
0.54
0.74
1.05
1.38
1.77
2.21
2.37
3.04
3.45
3.93
4.51
4.78
5.47
6.21
6.85
7.81
8.42
10.1
11.0
12.0
13.0
14.1
14.7
16.1
17.5
19.4
21.1
22.5
500.
360.
650.
881.
261.
652.
102.
622.
803.
584.
074.
645.
315.
706.
517.
408.
159.
2610
.011
.913
.014
.215
.416
.617
.319
.020
.722
.925
.026
.660
0.42
0.75
1.02
1.46
1.91
2.42
3.02
3.23
4.13
4.70
5.34
6.13
6.61
7.56
8.58
9.46
10.7
11.6
13.8
15.0
16.4
17.7
19.2
20.0
21.9
23.8
26.4
28.8
30.7
700.
480.
861.
161.
672.
172.
753.
433.
664.
685.
326.
056.
967.
538.
619.
7710
.812
.213
.215
.617
.018
.520
.121
.722
.724
.827
.030
.032
.734
.980
0.54
0.96
1.30
1.87
2.43
3.08
3.83
4.09
5.23
5.95
6.77
7.79
8.46
9.67
11.0
12.1
13.7
14.9
17.5
19.0
20.7
22.5
24.2
25.3
27.7
30.2
33.6
36.7
39.0
900.
601.
071.
44 2
.08
2.69
3.40
4.23
4.51
5.7
86.
587.
49 8
.62
9.38
10.7
12.2
13.4
15.2
16.5
19.3
21.0
22.
924
.9 2
6.8
28.0
30.7
33.5
37.
240
.643
.210
00.
66 1
.17
1.58
2.2
82.
953.
724.
634.
94 6
.33
7.22
8.21
9.46
10.3
11.8
13.4
14.7
16.6
18.0
21.1
23.0
25.1
27.
429
.430
.833
.736
.840
.944
.647
.55
0.05
30.
096
0.12
90.
191
0.25
30.
332
0.40
60.
450
0.58
20.
661
0.7
730.
899
0.97
71.
141.
281.
411.
551.
701.
902.
10 2
.30
2.48
2.74
2.83
3.16
3.41
3.78
4.12
4.32
10
0.06
90.
124
0.16
80.
246
0.32
40.
421
0.51
90.
564
0.73
00.
834
0.97
21.
12 1
.24
1.41
1.5
81.
791.
962.
182.
442.
682.
893.
133.
443.
584.
004.
304.
775.
165.
4315
0.07
50.
134
0.1
850.
268
0.35
10.
455
0.56
60.
614
0.79
2 0
.902
1.07
1.22
1.35
1.5
51.
751.
942.
19 2
.32
2.6
12.
853.
12 3
.34
3.65
3.78
4.20
4.51
5.05
5.4
55.
7220
0.07
50.
134
0.1
850.
268
0.35
10.
455
0.56
60.
614
0.79
20.
902
1.07
1.22
1.35
1.55
1.75
1.94
2.19
2.32
2.6
12.
853.
123.
343.
653.
784.
204.
515.
055.
455.
7230
0.07
50.
134
0.18
50.
268
0.35
10.
455
0.56
60.
614
0.79
20.
902
1.07
1.22
1.35
1.55
1.75
1.94
2.19
2.32
2.61
2.8
53.
123.
343.
653.
784.
20 4
.51
5.05
5.45
5.72
Supply Pressure – psig
Choked Flow
Vacuum LevelIn. Hg. Supply Pressure – psig
Choked Flow
Orif
ice
Dia
met
er0.
035
0.03
70.
038
0.03
90.
040
0.04
10.
042
0.04
30.
047
0.05
20.
055
0.06
00.
063
0.06
70.
070
0.07
30.
076
0.07
90.
081
0.08
60.
089
0.09
40.
096
0.10
00.
104
0.10
90.
113
0.12
00.
125
Inch
es
Siz
eN
umbe
r35
3738
3940
4142
4347
52
55 6
063
6770
7376
7981
8689
9496
100
104
109
113
120
125
Cv
0.02
80.
031
0.0
320.
033
0.03
60.
038
0.03
90.
041
0.04
80.
059
0.06
80.
081
0.08
80.
100.
110.
120.
13 0
.14
0.15
0.17
0.18
0.20
0.21
0.2
3 0
.25
0.27
0.31
0.34
0.37
13.
483.
834.
13 4
.46
4.60
4.67
4.99
5.36
6.4
38.
049.
4011
.212
.214
.215
.916
.918
.520
.321
.723
.525
.428
.430
.132
.935
.539
.643
.147
.850
.15
7.67
8.48
9.0
99.
7010
.210
.611
.312
.114
.217
.620
.3 2
3.9
26.1
30.3
33.
836
.139
.443
.146
.0 5
1.1
54.9
61.9
65.0
70.8
76.6
84.8
92.
110
210
810
10.6
11.8
12.5
13.6
14.4
14.8
15.6
16.8
19.4
24.
527
.132
.235
.240
.745
.648
.552
.957
.361
.667
.9 7
2.3
81.0
85.5
92.3
102
112
118
135
148
1513
.114
.515
.416
.717
.718
.219
.120
.4 2
3.6
29.7
32.9
39.0
42.6
49.3
55.
358
.864
.069
.474
.582
.187
.397
.810
311
112
313
514
316
317
820
15.3
17.0
18.1
19.6
20.9
21.
422
.524
.027
.735
.0 3
8.7
45.9
50.1
58.0
65.0
69.0
75.3
81.4
87.3
95.6
102
114
121
130
144
158
167
190
210
2517
.719
.620
.822
.624
.024
.725
.927
.631
.940
.344
.652
.857
.766
.774
.779
.386
.493
.510
011
011
713
113
814
916
418
019
121
924
130
20.0
22.
223
.625
.627
.228
.029
.431
.336
.045
.650
.459
.765
.275
.484
.389
.597
.410
511
312
513
214
815
616
818
520
421
624
827
340
24.8
27.4
31.7
31.6
33.6
34.6
36.3
38.7
44.5
56.3
62.2
73.6
80.3
92.
710
411
012
012
913
915
316
218
119
120
722
825
126
730
633
750
29.5
32.
634
.837
.640
.141
.343
.346
.052
.966
.974
.087
.495
.411
012
313
114
215
316
418
119
2 2
1522
724
727
2 2
9931
736
440
160
34.3
38.0
40.6
43.8
46.7
48.1
50.3
53.5
61.5
77.7
85.8
101
110
127
142
151
164
177
189
210
223
250
264
286
315
347
368
422
465
7039
.243
.346
.350
.053
.3 5
5.0
57.4
61.
070
.088
.497
.611
512
614
516
217
118
620
221
624
025
428
530
132
736
039
642
148
253
180
44.0
48.
752
.156
.260
.061
.9 6
4.5
68.5
78.6
99.1
109
129
141
162
181
191
209
227
242
269
285
320
338
367
404
445
472
541
596
9050
.054
.2 5
7.8
62.4
66.7
68.9
71.5
76.0
87.2
109
121
143
156
179
200
211
231
251
268
298
316
354
374
406
447
492
522
598
660
100
53.9
59.6
63.7
68.7
73.5
77.3
78.6
83.5
95.8
120
133
156
171
196
221
234
255
277
296
329
349
392
413
449
494
544
578
662
729
54.
925.
405.
816.
296.
766.
827.
297.
679.
0811
.312
.414
.817
.120
.0 2
2.5
23.9
26.0
28.
330
.233
.235
.940
.141
.845
.349
.053
.957
.965
.370
.910
6.18
6.78
7.29
7.8
58.
318.
509.
089.
5811
.113
.915
.418
.221
.224
.427
.229
.9 3
2.5
35.3
37.7
41.5
44.8
50.0
52.1
56.6
61.2
67.2
72.2
81.4
88.4
156.
507.
177.
638.
228.
668.
879.
4610
.011
.614
.415
.918
.622
.125
.528
.431
.233
.936
.839
.443
.346
.752
.154
.459
.063
.870
.175
.384
.992
.220
6.50
7.1
77.
638.
228.
66 8
.87
9.46
10.0
11.6
14.4
15.9
18.6
22.1
25.5
28.4
31.2
33.9
36.8
39.4
43.3
46.7
52.1
54.4
59.0
63.8
70.1
75.3
84.9
92.2
306.
50 7
.17
7.63
8.22
8.66
8.87
9.46
10.0
11.6
14.4
15.9
18.6
22.1
25.5
28.4
31.2
33.9
36.8
39.4
43.3
46.7
52.1
54.4
59.0
63.8
70.1
75.3
84.9
92.2
Vacuum LevelIn. Hg.
Sta
nd
ard
Co
nd
itio
ns
70
°F,
14
.7 p
sia
SC
FH
– S
tan
da
rd C
u.
Ft.
Pe
r H
ou
rA
bo
ve d
ata
ob
tain
ed
with
Typ
e B
re
stri
cto
r. F
low
ra
tes
for
oth
er
me
tal r
est
rict
ors
are
SL
PM
– S
tan
da
rd L
iters
Pe
r M
inu
tee
sse
ntia
lly t
he
sa
me
as
for
Typ
e B
. A
bo
ve d
ata
su
pe
rce
de
s p
revi
ou
s p
ub
lica
tion
s.
P
.O.
BO
X Q
•
T
RU
MB
UL
L,
CO
NN
EC
TIC
UT
06
61
1
•
C
T P
HO
NE
(2
03
) 2
61
-67
11
•
TO
LL
FR
EE
PH
ON
E (
80
0)
53
3-3
28
5
•
F
AX
(2
03
) 2
61
-83
31
©
O'K
EE
FE
CO
NT
RO
LS
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2
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w
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18
P
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BO
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EC
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UT
06
61
1
•
C
T P
HO
NE
(2
03
) 2
61
-67
11
•
TO
LL
FR
EE
PH
ON
E (
80
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53
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(2
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) 2
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©
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NT
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Sap
phire
Orif
ice
Air
Flo
w –
SLP
MO
rific
eD
iam
eter
0.00
120.
0016
0.00
200.
0024
0.00
280.
0031
0.00
350.
0039
0.00
430.
0047
0.00
510.
0055
0.00
590.
0063
0.00
670.
0071
0.00
790.
0087
0.00
940.
0102
0.01
100.
0118
0.01
260.
0134
0.01
420.
0157
0.01
730.
0189
0.02
050.
0213
0.02
280.
0252
Inch
es
Size
Num
ber
34
56
78
910
1112
1314
1516
1718
2022
2426
2830
3234
3640
4448
5254
5864
Cv
0.00
0030
0.00
0053
0.00
0090
0.00
012
0.00
017
0.00
022
0.00
028
0.00
035
0.00
042
0.00
050
0.00
061
0.00
071
0.00
084
0.00
094
0.00
110.
0012
0.00
150.
0018
0.00
210.
0024
0.00
280.
0032
0.00
360.
0040
0.00
460.
0057
0.00
670.
0080
0.00
910.
010
0.01
10.
013
10.
003
0.00
50.
010
0.01
40.
020
0.02
50.
034
0.04
00.
050
0.05
80.
068
0.08
00.
095
0.10
60.
120
0.13
90.
161
0.19
40.
259
0.27
50.
300
0.34
00.
393
0.44
60.
499
0.67
70.
822
0.96
51.
101.
121.
381.
69
50.
009
0.01
30.
027
0.03
60.
047
0.05
90.
076
0.09
30.
108
0.13
60.
159
0.19
20.
223
0.25
60.
273
0.31
30.
350
0.43
00.
584
0.62
30.
695
0.80
00.
933
1.06
1.20
1.51
1.81
2.16
2.50
2.57
3.26
4.06
100.
010
0.01
60.
036
0.04
90.
065
0.08
20.
107
0.13
20.
164
0.19
30.
228
0.26
40.
308
0.35
70.
382
0.43
00.
480
0.59
00.
830
0.86
80.
968
1.09
1.27
1.45
1.63
2.01
2.43
2.90
3.32
3.45
4.43
5.58
150.
014
0.02
10.
046
0.06
20.
082
0.10
40.
134
0.16
60.
205
0.24
00.
285
0.32
90.
386
0.44
30.
482
0.53
50.
613
0.75
51.
051.
111.
241.
421.
631.
852.
092.
563.
083.
694.
264.
435.
557.
0820
0.01
60.
025
0.05
50.
074
0.09
90.
125
0.15
90.
197
0.24
30.
284
0.33
70.
390
0.45
70.
525
0.56
90.
635
0.73
00.
910
1.25
1.32
1.48
1.70
1.95
2.20
2.48
3.04
3.64
4.36
5.06
5.31
6.55
8.33
250.
019
0.03
00.
063
0.08
70.
115
0.14
40.
184
0.22
90.
280
0.32
70.
389
0.45
00.
526
0.60
50.
654
0.73
30.
843
1.05
1.44
1.52
1.70
1.95
2.24
2.52
2.84
3.50
4.19
5.03
5.81
6.11
7.53
9.55
300.
022
0.03
40.
072
0.09
80.
132
0.16
40.
208
0.26
00.
317
0.37
00.
440
0.51
10.
595
0.68
50.
710
0.83
80.
958
1.19
1.63
1.69
1.91
2.19
2.52
2.84
3.19
3.96
4.75
5.69
6.57
6.90
8.48
10.7
400.
027
0.04
30.
089
0.12
20.
163
0.20
30.
257
0.32
10.
390
0.45
60.
543
0.63
20.
734
0.84
50.
880
1.04
1.18
1.47
2.02
2.11
2.35
2.67
3.07
3.46
3.90
4.89
5.86
7.02
8.10
8.50
10.4
13.1
500.
032
0.05
20.
106
0.14
70.
195
0.24
10.
306
0.38
30.
463
0.54
20.
652
0.75
30.
872
1.00
1.05
1.24
1.41
1.75
2.39
2.50
2.78
3.16
3.63
4.08
4.59
5.83
6.96
8.35
9.63
10.1
12.3
15.5
600.
037
0.06
10.
123
0.17
10.
227
0.28
00.
356
0.44
50.
536
0.63
00.
751
0.87
51.
011.
161.
231.
451.
642.
032.
772.
893.
203.
634.
174.
695.
296.
778.
109.
6911
.111
.714
.217
.9
700.
042
0.07
00.
141
0.19
50.
259
0.31
80.
403
0.50
70.
609
0.71
70.
855
0.99
61.
151.
321.
401.
661.
872.
313.
143.
283.
624.
124.
725.
315.
997.
719.
2311
.012
.713
.316
.020
.2
800.
047
0.08
00.
158
0.20
00.
292
0.35
70.
453
0.56
90.
683
0.80
40.
959
1.12
1.28
1.48
1.57
1.86
2.09
2.59
3.51
3.66
4.04
4.68
5.28
5.93
6.69
8.65
10.4
12.3
14.3
14.8
17.9
22.6
900.
053
0.08
90.
175
0.24
40.
324
0.39
60.
502
0.63
20.
757
0.89
11.
061.
241.
421.
641.
752.
062.
322.
873.
894.
054.
475.
075.
836.
567.
419.
6011
.513
.715
.716
.419
.724
.9
100
0.05
80.
098
0.19
30.
269
0.35
60.
435
0.55
10.
692
0.83
00.
978
1.17
1.36
1.56
1.80
1.92
2.27
2.55
3.15
4.26
4.44
4.89
5.57
6.38
7.18
8.12
10.6
12.6
15.0
17.2
18.0
21.6
27.3
50.
003
0.00
60.
014
0.02
00.
028
0.03
60.
047
0.05
70.
073
0.08
50.
100
0.11
60.
137
0.15
60.
169
0.19
90.
229
0.27
70.
377
0.40
10.
451
0.51
00.
591
0.67
30.
764
0.98
21.
161.
381.
611.
642.
132.
61
10
0.00
40.
008
0.01
80.
027
0.03
60.
046
0.06
10.
073
0.09
30.
109
0.12
80.
149
0.17
50.
200
0.21
70.
253
0.29
20.
352
0.48
20.
503
0.55
60.
638
0.73
40.
833
0.95
51.
261.
511.
802.
062.
112.
553.
19
150.
006
0.01
0 0
.021
0.03
00.
040
0.05
00.
065
0.07
90.
100
0.1
170.
138
0.15
90.
188
0.21
40.
235
0.26
90.
320
0.39
00.
525
0.55
40.
626
0.71
10.
818
0.92
11.
071.
391.
651.
992.
312.
392.
773.
48
200.
006
0.01
0 0
.021
0.03
00.
040
0.05
00.
065
0.07
90.
100
0.11
70.
138
0.15
90.
188
0.21
40.
235
0.26
90.
320
0.39
00.
525
0.55
40.
626
0.71
10.
818
0.92
11.
071.
391.
651.
992.
312.
392.
773.
48
300.
006
0.01
00.
021
0.03
00.
040
0.05
00.
065
0.07
90.
100
0.11
70.
138
0.15
90.
188
0.21
40.
235
0.26
90.
320
0.39
00.
525
0.55
40.
626
0.71
10.
818
0.92
11.
071.
391.
651.
992.
312.
392.
773.
48
Supply Pressure – psig
Choked Flow
Supply Pressure – psig
Choked Flow
Orif
ice
Dia
met
er0.
0012
0.00
160.
0020
0.00
240.
0028
0.00
310.
0035
0.00
390.
0043
0.00
470.
0051
0.00
550.
0059
0.00
630.
0067
0.00
710.
0079
0.00
870.
0094
0.01
020.
0110
0.01
180.
0126
0.01
340.
0142
0.01
570.
0173
0.01
890.
0205
0.02
130.
0228
0.02
52
Inch
es
Siz
eN
umbe
r3
45
67
89
1011
1213
1415
1617
1820
2224
2628
3032
3436
4044
4852
5458
64
Cv
0.00
0030
0.00
0053
0.00
0090
0.00
012
0.00
017
0.00
022
0.00
028
0.00
035
0.00
042
0.00
050
0.00
061
0.00
071
0.00
084
0.00
094
0.00
110.
0012
0.00
150.
0018
0.00
210.
0024
0.00
280.
0032
0.00
360.
0040
0.00
460.
0057
0.00
670.
0080
0.00
910.
010
0.01
10.
013
10.
007
0.01
10.
021
0.03
00.
042
0.05
30.
072
0.08
50.
106
0.12
30.
144
0.16
90.
201
0.22
50.
254
0.29
40.
341
0.41
10.
549
0.58
30.
636
0.72
00.
833
0.94
51.
061.
431.
742.
042.
332.
372.
923.
58
50.
019
0.02
70.
056
0.07
50.
100
0.12
40.
161
0.19
70.
228
0.28
80.
337
0.40
70.
471
0.54
20.
577
0.66
30.
740
0.91
11.
241.
321.
471.
701.
982.
252.
533.
203.
834.
585.
305.
446.
908.
60
100.
021
0.03
40.
076
0.10
40.
138
0.17
40.
227
0.28
00.
347
0.40
90.
483
0.55
90.
653
0.75
60.
809
0.91
11.
021.
251.
761.
842.
052.
312.
693.
073.
454.
265.
156.
147.
037.
319.
3911
.8
150.
030
0.04
40.
097
0.13
10.
174
0.22
00.
284
0.35
20.
434
0.50
80.
604
0.69
70.
818
0.93
91.
021.
131.
301.
602.
222.
352.
633.
013.
453.
924.
435.
426.
537.
829.
039.
3911
.815
.020
0.03
40.
053
0.11
70.
157
0.21
00.
265
0.33
70.
417
0.51
50.
602
0.71
40.
826
0.96
81.
111.
211.
351.
551.
932.
652.
803.
143.
604.
134.
665.
256.
447.
719.
2410
.711
.313
.917
.6
250.
040
0.06
40.
133
0.18
40.
244
0.30
50.
390
0.48
50.
593
0.69
30.
824
0.95
31.
111.
281.
391.
551.
792.
223.
053.
223.
604.
134.
755.
346.
027.
428.
8810
.712
.312
.916
.020
.2
300.
046
0.07
20.
152
0.20
80.
280
0.34
70.
441
0.55
10.
672
0.78
40.
932
1.08
1.26
1.45
1.50
1.78
2.03
2.52
3.45
3.58
4.05
4.64
5.34
6.02
6.76
8.39
10.1
12.1
13.9
14.6
18.0
22.7
400.
057
0.09
10.
189
0.25
80.
345
0.43
00.
544
0.68
00.
826
0.96
61.
151.
341.
561.
791.
862.
202.
503.
114.
284.
474.
985.
666.
507.
338.
2610
.412
.414
.917
.218
.022
.027
.8
500.
068
0.11
00.
225
0.31
10.
413
0.51
10.
648
0.81
10.
981
1.15
1.38
1.60
1.85
2.13
2.22
2.63
2.99
3.71
5.06
5.30
5.89
6.69
7.69
8.64
9.72
12.4
14.7
17.7
20.4
21.4
26.1
32.8
600.
079
0.12
90.
261
0.36
20.
481
0.59
30.
754
0.94
31.
141.
331.
591.
852.
142.
462.
613.
073.
474.
305.
876.
126.
787.
698.
839.
9411
.214
.317
.220
.523
.524
.830
.137
.9
700.
089
0.14
90.
299
0.41
30.
549
0.67
40.
854
1.07
1.29
1.52
1.81
2.11
2.43
2.80
2.97
3.52
3.96
4.89
6.65
6.95
7.67
8.73
10.0
11.3
12.7
16.3
19.6
23.3
26.9
28.2
33.9
42.8
800.
100
0.16
80.
335
0.42
40.
619
0.75
60.
960
1.21
1.45
1.70
2.03
2.37
2.72
3.13
3.33
3.94
4.43
5.49
7.44
7.75
8.56
9.75
11.2
12.6
14.2
18.3
22.0
26.1
30.3
31.4
37.9
47.9
900.
111
0.18
80.
371
0.51
70.
686
0.83
91.
061.
341.
601.
892.
252.
623.
013.
473.
714.
364.
926.
088.
248.
589.
4710
.712
.413
.915
.720
.324
.429
.033
.334
.741
.752
.8
100
0.12
20.
208
0.40
90.
570
0.75
40.
922
1.17
1.47
1.76
2.07
2.47
2.88
3.30
3.81
4.07
4.81
5.40
6.67
9.03
9.41
10.4
11.
813
.515
.217
.222
.526
.731
.836
.438
.145
.857
.8
50.
007
0.01
30.
029
0.04
30.
059
0.07
60.
100
0.12
10.
154
0.18
00.
212
0.24
60.
290
0.33
10.
358
0.42
20.
485
0.58
70.
799
0.85
00.
956
1.08
1.25
1.43
1.62
2.08
2.46
2.92
3.41
3.47
4.51
5.53
100.
009
0.01
80.
039
0.05
70.
076
0.09
80.
128
0.15
50.
197
0.23
10.
271
0.31
60.
371
0.42
40.
460
0.53
60.
619
0.74
61.
021.
071.
181.
351.
561.
762.
022.
673.
193.
814.
364.
475.
406.
76
150.
012
0.02
00.
045
0.06
30.
085
0.10
70.
138
0.16
80.
212
0.24
80.
292
0.33
70.
398
0.45
30.
498
0.57
00.
678
0.82
61.
111.
171.
331.
511.
731.
952.
262.
953.
504.
224.
895.
065.
877.
37
200.
012
0.02
00.
045
0.06
30.
085
0.10
70.
138
0.16
80.
212
0.24
80.
292
0.33
70.
398
0.45
30.
498
0.57
00.
678
0.82
61.
111.
171.
331.
511.
731.
952.
262.
953.
504.
224.
895.
065.
877.
37
300.
012
0.02
00.
045
0.06
30.
085
0.10
70.
138
0.16
80.
212
0.24
80.
292
0.33
70.
398
0.45
30.
498
0.57
00.
678
0.82
61.
111.
171.
331.
511.
731.
952.
262.
953.
504.
224.
895.
065.
877.
37
Vacuum LevelIn. Hg.
Sta
nd
ard
Co
nd
itio
ns
70
°F,
14
.7 p
sia
SC
FH
– S
tan
da
rd C
u.
Ft.
Pe
r H
ou
rA
bo
ve d
ata
ob
tain
ed
with
Typ
e S
re
stri
cto
r. F
low
ra
tes
for
Typ
e A
, B
TF
, B
WF
, F
, J,
SL
PM
– S
tan
da
rd L
iters
Pe
r M
inu
teL
, P
, a
nd
SF
re
stri
cto
rs a
re e
sse
ntia
lly t
he
sa
me
as
for
Typ
e S
.A
bo
ve d
ata
su
pe
rce
de
s p
revi
ou
s p
ub
lica
tion
s.
Sap
phire
Orif
ice
Air
Flo
w –
SC
FH
Vacuum LevelIn. Hg.