Document 377KmVZmoo4xZrgdMXz4k2B7a
Heating Ventilating Air Conditioning Guide 1939
Boiling Point of Water. The boiling point of water varies with the pressure; it is lower at higher altitudes. A change in pressure will always be accompanied by a change in the boiling point, and there will be a cor responding change in. the latent heat of evaporation. These values are given in Table 8.
Specific Heat. The specific heat of water, or the amount of heat (Btu) required to raise the temperature of one pound of water one degree Fahren heit, varies with the temperature, but it is commonly assumed to be
Table 7. Thermal Properties of Water
Tempebaturs Deo F
32 40 50 60 70 80 90 100 110 120 130 140.
ISO
160 170 180 190 200 210 212 220 240 260 280 300 350 400 450 500 550 600 700
Sat. Press. Lb per Sq In.
0.0887 0.1217 0.1780 0.2561 0.3628 0.5067
0.6980 0.9487 1.274 1.692 2.221 2.887
3.716 4.739
5.990 7.510 9.336 11.525 14.123 14.696 17.188 24.97 35.43 49.20 67.01 134.62 247.25 422.61 681.09 1045.4 1544.6 3096.4
Volume Cu Ft psb Lb
0.01602 0.01602 0.01602 0.01603 0.01605 0.01607 0.01610 0.01613 0.01616 0.01620 0.01625 0.01629 0.01634 0.01639 0.01645 0.01650 0 01656 0.01663 0.01669 0.01670 0.01676 0.01690 0.01706 0.01723 0.01742 0.01797 . 0.01865 0.01950 0.02050 . 0.02190 0.02410 0:03940 ' .
Weight Lb per Cu Ft
62.42 62.42 62.42 62.38 62.31 62.23 62.11 62.00 61.88 61.73 61.54 61.39 61.20 61.01 60.79 60.61 60.39 60.13 59.92 59.88 59.66 59.17 58.62 58.04 57.41 55.65 53.62 51.30 48.80 45.70 41.50 25.40
Specific Heat
1.0093 1.0048 1.0015 0.9995 0.9982 0.9975 0.9971 0.9970 0.9971 0.9974' 0.9978 0.9984 0.9990 0.9998 1.0007 1.0017 1.0028 1.0039 1.0052 1.0055 1.0068 1.0104 1.0148 1.0200 1.0260 1.0440 1.0670 1.0950 1.1300 1.2000 1.3620
unity at all temperatures. Steam tables are based on exact values, however. The specific heat of ice at 32 F is 0.492 Btu per pound. The amount of heat required to raise one pound of water at 32 F through a known temperature interval depends on the average specific heat for the temperature range.
. Sensible and. Latent Heat. The heat necessary to raise the temperature of one pound of water from 32 F to the boiling point is known as the heat of the.liquid or sensible heati When more heat is added, the water begins to evaporate and expand at constant temperature until the water, is entirely changed into steam. The hfeat thus added is known as the latent heat of evaporation.
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Chapter 1. Air, Water and Steam
Table 8. Properties of Saturated Steam: Pressure Table*
Abs. Press. In. He.
P
Temp F t
Specific Volume
Sat.
Liquid Vf
Sat. Vapor
y
Enthalpy
Entropy
Sat.
Liquid hf
Evap. hfg
Sat. Sat. Vapor Liquid
h* Sf
Evap. Sfg
Sat. Vapor
St
nua.
Press. In. He.
P
0.25 0.50 0.75
1.00 1.5
40.23 58.80 70.43 79.03
91.72
0.01602
0.01604 0.01606 0.02608 0.01611
2423.7 1256.4 856.1
652.3 444.9
8.28 26.86
38.47 47.05
59.71
1071.1
1060.6 1054.0 1049.2
1042.0
1079.4
1087.5 1092.5 1096.3 1101.7
0.0166 0.0532 0.0754 0.0914 0.1147
2.1423 2.0453 1.9881 1.9473
1.8894
2.0986
2.0635 2.0387
2.0041
0.50 0.75 1.00
1.5
2 4
6
8 10
101.14 125.43 140.78 152.24
161.49
0.01614
339.2
0.01622
176.7
0.01630 120.72
0.01635
92.16
0.01640
74.76
69.10 93.34 108.67 120.13 129.38
1036.6 I 1105.7 I 0.1316 1022.7 1116.0 0.1738 1013.6 1122.3 0.1996 1006.9 1127.0 0.2186 1001.4 1130.8 0.2335
1.8481
1.7476 1.6881
1.6454 1.6121
1.9797
1.9214 1.8877 1.8640 1.8456
2.0 4.0 6 8
10
12 169.28 0.01644 14 176.05 0.01648 16 1S2.05 0.01652 18 187.45 0:01655 20 192.37 0.02658
63.03 54.55
48.14
43.11 39.07
137.18 143.96
149.98 i 155.39 160,33
996.7 1133.9 992.6 1136.6 988.9 U3S.9 985.7 1141.1 982.7 I 1143.0
0.2460
0.2568 0.2662
0.2746 0.2822
1.5847
1.5613 1.5410 1.5231 1.5069
1.8307
1.8181 1.8072 1.7977 , 1.7891 I
12 14 16 18
20
22 196.90 0.01661 24 201.09 0.01664 26 205.00 0.01667 28 208.67 0.01669 30 212.13 0.01672 Lb
35.73 32.94
30.56 28.52 26.74
164.87 169.09 173.02 176.72
180.19
979.8 977.2
974.8 972.5 970.3
1144.7
1146.3 1147.8 1149.2 1150.5
0.2891 0.2955
0.3014 0.3069 0.3122
1.4923 1.4789 1.4665
1.4550 1.4442
17814 1.7744
1.7679 1.7619 1.7564
22 24 26 28
30
Sq In.
Lb
14.696 16 18 20 22
24 26 28
212.00 216.32 222.41
227.96 233.07 237.82 242.25 246.41
0.01672
26.80 180.07
0.01674 - 24.75 184.42
0.01679 0.01683 0.01687
22.17 190.56 20.089 196.16 18.375 201,33
0.01691
16.938 206.14
0.01694
15.715 210.62
0.01698
14.663 214.83
970.3 967.6 963.6 960.1 956.8 953.7 950.7
947.9
1150.4 1152.0 1154.2
1156.3 1158.1 1159.8 1161.3 1162.7
0.3120 0.3184 0.3275 0.3356 0.3431 0.3500 0.3564
0.3623
1.4446 1.4313 1.4128 1.3962 1.3811
1.3672 1.3544
1.3425
1.7566 1.7497 1.7403 1.7319 1.7242 1.7172
1.7108 1.7048
Sq In.
14.696 16 18 20 22
24 26 28
30 250.33 0.01701 32 254.05 0.01704 34 257.58 0.01707
260.95 0.01709 38 264.16 0.01712
13.746 12.940 12.226
11.588 11.015
218.82 222.59
226.18 229.60 232.89
945.3
942.8 940.3
938.0 935.8
1164.1 1165.4 1106.5
1167.6 1168.7
0.3680 0.3733 0.3783
0.3831 0.3876
1.3313 1.3200 1.3110 1.3017 1.2929
1.6993
1.6941 1.6893 1.6848 1.6805
30
32 34 36
38
40 42
267.25 0.01715 270.21 0.01717
44 46
273.05 0.01720 275.80 0.01722
48 278.45 0.01725
10.498 10.029 9.601
9.209 8.848
236.03 239.04
241.95 244.75 247.47
933.7 931.6
929.6 927.7
925.8
1169.7 1170.7 1171.0 1172.4
1173.3
0.3919
0.3960 0.4000 0.4038 0.4075
1.2844 1.2764
1.2687 1.2613 1.2542
1.6763
1.6724 1.6687
1.6652 1.6617
40 42 44 46 48
50 52
54
56 58
281.01 283.49 285.90
288.23 290.50
0.01727 0.01729 0.01731 0.01733 0.01730
60 62 64 66
68
292.71 294.85 296,94 298.99 300.98
0.01738 0.01740 0.01742
0.01744
0.01746
70
72 74 76 78
302.92 304.83
306.68 308.50 310.29
0.01748
0.01750 0.01752 0.01754
0.01755
su
82
84 86 88
312.03 313.74
315.42 317.07
318.68
0.01757 0.01759 0.01761 0.01762
0.01764
90
92
94 96
98
320.27
321.83 323.30 324.87
326.35
0.01766
0.01768 0.01769 0.01771 0.01772
8.515 8.208
7.922 7.656 7.407
250.09
252.63 255.09
257.50 259.82
6.957 6.752
6.560 6.378
262.09
26430 266.45 268.55 270.60
6.206
6.044 5.890 5.743 5.604
272.61
274.57
276.49 278.37 280.21
5.472 5.346 5.226 5.111
[ 282.02
1 283.79 285.53 287.24 288.91
4.896 4.796 4.699
4.606 4.517
290.56 292.18 293.78 296.34
296.89
924.0 922.2
920.5
918.8 917.1
1174.1
1174.8 1175.6 1176.3 2170.9
0.4110 0.4144 0.4177 0.4209
0.4240
1.2474
1.2409 1.2346 1.2285 1.2226
1.6585 1.6553 1.6523
1.6494
1.6466
915.5 1177.0
913.9 .1178.2 912.3 1178.8 910.8 1179.4 909.4 `1180.0
0.4270 0.4300 0.4328 0.4356
0.4383
1.2168
1.2112 1.2059
1.2006 1.1955
1.6438 1.6412
1.6387 1.6362
1.6338
907.9 906.5 905.1 903.7
902.4
1180.6 1181.1 1181.6 1282.1
1182.6
0.4409 0.4435 0.4460 0.4484
0.4508
1.1857
1.1810 1.1764 1.1720
1.6315 1.6292
1.6270
1.6248 1.6228
901.1
899.7 898.5 897.2 895.9
1183.1
.1183.5 1184.0 1184.4 1184.8
0.4531
0.4554 0.4576 0.4598 0.4620
1.1676 1.1633 1.1592 1.1551 1.1510
1.6207 1.6187
1.6168 1.6149 1.6130
894.7 1185.3 893.5 1185.7 892.3 , 1186.1 891.1 1186.4 $89.9 1186.8
0.4641 1.1471 0.4661 1.1433 0.4682 , 1.1394 0.4702 1.1358 0.4721 1.1322
1.6112 1.6094 1.6076
1.6060 1.6043
50 52 54 56 58
60 62 64 66 68
70 72 74 76 78
80 82 84 86 88
90 92 94 96. 98
PUbh& b^Jota
Tha^dynamic Properties of Steam, by J. H. Keenan and F. G. Keyes.
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