NTP - Normal Temperature and Pressure - is defined as air at 20oC (293.15 K, 68oF) and 1 atm ( 101.325 kN/m2, 101.325 kPa, 14.7 psia, 0 psig, 30 in Hg, 760 torr) |
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http://www.engineeringtoolbox.com/specific-gravities-gases-d_334.html |
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density of air defined http://hypertextbook.com/facts/2000/RachelChu.shtml using 1.25 kg/m3 |
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Saturated Water Vapor Pressure in mb es |
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Saturated vapor density vs Temp C |
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1.25 |
kg/m3 |
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density of dry air 0C & 760mm |
es=6.112*EXP(17.87*B62/(B62+243.5)) |
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VD=6.335 + .6718TC – 2.0887 x10-2TC2 + 7.3095 x 10-4TC3 |
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Bolton (1980) (0.3% within -35C to 35C) |
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density of dry air. |
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sat. vapor density(1) |
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3.5/(B7+253) |
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sat. vapor density |
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change in density from 0C |
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Temp F. |
Temp. Celsius |
gm/m3 |
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gr/m3 |
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gm/m3 |
kg/m3 |
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Temp. Celsius |
Temp F. |
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pws = e(77.3450 + 0.0057 T - 7,235 / T) / T8.2 (1)(77.3450 + 0.0057 T - 7,235 / T) /T 8.2 |
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-31 |
-35 |
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0.314764 |
18.090698 |
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-74.104056 |
0.015982 |
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1.433708 |
183.707747 |
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-35 |
-31 |
-29.2 |
-34 |
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0.347347 |
19.952821 |
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-69.380831 |
0.015909 |
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1.427713 |
177.712733 |
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-34 |
-29.2 |
-27.4 |
-33 |
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0.382945 |
21.986533 |
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0.015837 |
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1.421768 |
171.767645 |
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-33 |
-27.4 |
-25.6 |
-32 |
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0.421801 |
24.205712 |
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0.015766 |
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1.415872 |
165.871864 |
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-32 |
-25.6 |
-23.8 |
-31 |
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0.464178 |
26.62519 |
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0.015695 |
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1.410025 |
160.024778 |
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-31 |
-23.8 |
-22 |
-30 |
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0.510354 |
29.260811 |
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0.015625 |
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1.404226 |
154.225787 |
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-30 |
-22 |
-20.2 |
-29 |
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0.560628 |
32.129481 |
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0.015556 |
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1.398474 |
148.474299 |
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-29 |
-20.2 |
-18.4 |
-28 |
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0.615318 |
35.24923 |
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0.015487 |
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1.39277 |
142.769733 |
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-28 |
-18.4 |
-16.6 |
-27 |
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0.674762 |
38.639269 |
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0.015419 |
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1.387112 |
137.111517 |
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-27 |
-16.6 |
-14.8 |
-26 |
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0.739322 |
42.320052 |
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0.015351 |
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1.381499 |
131.49909 |
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-26 |
-14.8 |
-13 |
-25 |
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0.809381 |
46.313344 |
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0.015284 |
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1.375932 |
125.931896 |
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-25 |
-13 |
-11.2 |
-24 |
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0.885349 |
50.642283 |
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0.015217 |
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1.370409 |
120.409392 |
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-24 |
-11.2 |
-9.4 |
-23 |
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0.967659 |
55.331451 |
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0.015152 |
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1.364931 |
114.931041 |
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-23 |
-9.4 |
-7.6 |
-22 |
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1.056773 |
60.406947 |
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0.015086 |
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1.359496 |
109.496317 |
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-22 |
-7.6 |
-5.8 |
-21 |
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1.15318 |
65.896459 |
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0.015021 |
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1.354105 |
104.1047 |
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-21 |
-5.8 |
-4 |
-20 |
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1.2574 |
71.829342 |
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-18.258259 |
0.014957 |
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1.348756 |
98.755678 |
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-20 |
-4 |
-2.2 |
-19 |
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1.369982 |
78.236694 |
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0.014894 |
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1.343449 |
93.448751 |
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-19 |
-2.2 |
-0.4 |
-18 |
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1.491509 |
85.151441 |
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0.014831 |
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1.338183 |
88.183422 |
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-18 |
-0.4 |
1.4 |
-17 |
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1.622599 |
92.608419 |
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0.014768 |
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1.332959 |
82.959204 |
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-17 |
1.4 |
3.2 |
-16 |
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1.763903 |
100.644462 |
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0.014706 |
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1.327776 |
77.775617 |
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-16 |
3.2 |
5 |
-15 |
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1.916111 |
109.298488 |
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0.014644 |
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1.322632 |
72.632191 |
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-15 |
5 |
6.8 |
-14 |
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2.079954 |
118.611595 |
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0.014583 |
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1.317528 |
67.528458 |
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-14 |
6.8 |
8.6 |
-13 |
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2.256199 |
128.627153 |
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0.014523 |
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1.312464 |
62.463963 |
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-13 |
8.6 |
10.4 |
-12 |
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2.445659 |
139.390899 |
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0.014463 |
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1.307438 |
57.438254 |
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-12 |
10.4 |
12.2 |
-11 |
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2.64919 |
150.951042 |
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0.014403 |
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1.302451 |
52.450887 |
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-11 |
12.2 |
14 |
-10 |
2.36 |
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2.867696 |
163.35836 |
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-2.822007 |
0.014344 |
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2.36 |
1.297501 |
47.501425 |
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-10 |
14 |
15.8 |
-9 |
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3.102126 |
176.666309 |
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0.014286 |
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1.292589 |
42.589438 |
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-9 |
15.8 |
17.6 |
-8 |
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3.353482 |
190.931125 |
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0.014228 |
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1.287715 |
37.714501 |
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-8 |
17.6 |
19.4 |
-7 |
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3.622817 |
206.211943 |
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0.01417 |
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1.282876 |
32.876198 |
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-7 |
19.4 |
21.2 |
-6 |
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3.911238 |
222.5709 |
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0.014113 |
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1.278074 |
28.074116 |
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-6 |
21.2 |
23 |
-5 |
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4.21991 |
240.073258 |
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0.014056 |
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1.273308 |
23.30785 |
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-5 |
23 |
24.8 |
-4 |
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4.550055 |
258.787518 |
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0.014 |
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1.268577 |
18.577002 |
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-4 |
24.8 |
26.6 |
-3 |
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4.902956 |
278.785542 |
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0.013944 |
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1.263881 |
13.881177 |
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-3 |
26.6 |
28.4 |
-2 |
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5.279961 |
300.142678 |
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0.013889 |
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1.25922 |
9.219989 |
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-2 |
28.4 |
30.2 |
-1 |
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5.682482 |
322.937883 |
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0.013834 |
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1.254593 |
4.593055 |
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-1 |
30.2 |
32 |
0 |
4.85 |
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6.112 |
347.253851 |
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6.335 |
0.01378 |
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4.85 |
1.25 |
0 |
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0 |
32 |
33.8 |
1 |
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6.570067 |
373.177149 |
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0.013725 |
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1.24544 |
-4.559548 |
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1 |
33.8 |
35.6 |
2 |
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7.058307 |
400.798345 |
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0.013672 |
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1.240914 |
-9.085953 |
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2 |
35.6 |
37.4 |
3 |
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7.57842 |
430.212146 |
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0.013619 |
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1.23642 |
-13.579576 |
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3 |
37.4 |
39.2 |
4 |
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8.132186 |
461.517539 |
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0.013566 |
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1.231959 |
-18.040772 |
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4 |
39.2 |
41 |
5 |
6.8 |
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8.721465 |
494.817928 |
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0.013514 |
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6.8 |
1.22753 |
-22.46989 |
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5 |
41 |
42.8 |
6 |
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9.348201 |
530.221277 |
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0.013462 |
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1.223133 |
-26.867276 |
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6 |
42.8 |
44.6 |
7 |
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10.014425 |
567.84026 |
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0.01341 |
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1.218767 |
-31.233268 |
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7 |
44.6 |
46.4 |
8 |
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10.722257 |
607.792404 |
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0.013359 |
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1.214432 |
-35.568202 |
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8 |
46.4 |
48.2 |
9 |
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11.473911 |
650.200242 |
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0.013308 |
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1.210128 |
-39.872408 |
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9 |
48.2 |
50 |
10 |
9.4 |
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12.271696 |
695.191465 |
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0.013258 |
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9.4 |
1.205854 |
-44.146212 |
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10 |
50 |
51.8 |
11 |
10.01 |
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13.11802 |
742.899075 |
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0.013208 |
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10.01 |
1.20161 |
-48.389935 |
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11 |
51.8 |
53.6 |
12 |
10.66 |
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14.015393 |
793.461543 |
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0.013158 |
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10.66 |
1.197396 |
-52.603893 |
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12 |
53.6 |
55.4 |
13 |
11.35 |
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14.966429 |
847.022965 |
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0.013109 |
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11.35 |
1.193212 |
-56.788398 |
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13 |
55.4 |
57.2 |
14 |
12.07 |
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15.973851 |
903.733226 |
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0.01306 |
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12.07 |
1.189056 |
-60.943758 |
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14 |
57.2 |
59 |
15 |
12.83 |
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17.040495 |
963.748161 |
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0.013011 |
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12.83 |
1.18493 |
-65.070276 |
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15 |
59 |
60.8 |
16 |
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18.169308 |
1027.229719 |
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0.012963 |
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1.180832 |
-69.168252 |
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16 |
60.8 |
62.6 |
17 |
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19.363361 |
1094.346127 |
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0.012915 |
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1.176762 |
-73.23798 |
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17 |
62.6 |
64.4 |
18 |
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20.62584 |
1165.272064 |
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0.012868 |
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1.17272 |
-77.279753 |
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18 |
64.4 |
66.2 |
19 |
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21.960063 |
1240.188821 |
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0.012821 |
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1.168706 |
-81.293856 |
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19 |
66.2 |
68 |
20 |
17.3 |
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23.369471 |
1319.284481 |
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0.012774 |
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17.3 |
1.164719 |
-85.280573 |
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20 |
68 |
69.8 |
21 |
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24.857641 |
1402.754088 |
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24.857641 |
0.012727 |
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1.16076 |
-89.240184 |
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21 |
69.8 |
71.6 |
22 |
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26.428285 |
1490.799818 |
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0.012681 |
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1.156827 |
-93.172963 |
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22 |
71.6 |
73.4 |
23 |
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28.085254 |
1583.631158 |
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0.012635 |
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1.152921 |
-97.079183 |
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23 |
73.4 |
75.2 |
24 |
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29.832543 |
1681.465082 |
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0.01259 |
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1.149041 |
-100.959112 |
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24 |
75.2 |
77 |
25 |
23 |
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31.674294 |
1784.526227 |
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0.012545 |
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23 |
1.145187 |
-104.813014 |
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25 |
77 |
78.8 |
26 |
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33.614801 |
1893.047074 |
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0.0125 |
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1.141359 |
-108.64115 |
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26 |
78.8 |
80.6 |
27 |
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35.658512 |
2007.268125 |
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0.012456 |
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1.137556 |
-112.443778 |
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27 |
80.6 |
82.4 |
28 |
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37.810033 |
2127.438087 |
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0.012411 |
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1.133779 |
-116.221152 |
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28 |
82.4 |
84.2 |
29 |
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40.074135 |
2253.814049 |
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0.012367 |
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1.130026 |
-119.973523 |
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29 |
84.2 |
86 |
30 |
30.4 |
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42.455754 |
2386.66167 |
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43.397434 |
0.012324 |
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30.4 |
1.126299 |
-123.701138 |
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30 |
86 |
87.8 |
31 |
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44.959999 |
2526.255358 |
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0.012281 |
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1.122596 |
-127.404241 |
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31 |
87.8 |
89.6 |
32 |
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47.592151 |
2672.878453 |
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0.012238 |
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1.118917 |
-131.083074 |
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32 |
89.6 |
91.4 |
33 |
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50.357672 |
2826.823413 |
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0.012195 |
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1.115262 |
-134.737874 |
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33 |
91.4 |
93.2 |
34 |
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53.262207 |
2988.391999 |
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0.012153 |
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1.111631 |
-138.368875 |
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34 |
93.2 |
95 |
35 |
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56.31159 |
3157.895458 |
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0.012111 |
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1.108024 |
-141.97631 |
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35 |
95 |
96.8 |
36 |
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3335.654706 |
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36 |
96.8 |
98.6 |
37 |
44 |
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3522.000518 |
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44 |
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37 |
98.6 |
100.4 |
38 |
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3717.273708 |
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38 |
100.4 |
102.2 |
39 |
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3921.825315 |
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39 |
102.2 |
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40 |
51.1 |
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4136.016789 |
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51.1 |
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40 |
104 |
Temp F. |
Temp. Celsius |
(1) values above from: http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/watvap.html#c1 |
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equation above from http://hurri.kean.edu/~yoh/calculations/moisture/Equations/moist.html |
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pws = e(77.3450 + 0.0057 T - 7,235 / T) / T8.2 (1)(77.3450 + 0.0057 T - 7,235 / T) /T 8.2 |
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equation above from http://www.engineeringtoolbox.com/water-vapor-saturation-pressure-air-d_689.html |
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