Document gbKGnLqGwqjB34Bm5nw6oojG9
HEATINC VENTILATINC AIR CONDITIONING GUIDE 1941
Table 5. Properties of Monofluo^otrichloromethane (Fu)
Sat.
Temp. F
AB8.
Lb peb So Is.
Volume liquid Vapor
Heat Content and Entboft Taken From --<o F
Heat Content liquid Vapor
Entropy liquid Vapor
25 F Superheat 50 F Superheat HL CL I Entropy: Ht CL Entropy
0 5 10 IS
20
25
2.59. 0.01020 13.700 2.96 0.01024! 12.100 3.38 0.01028| 10.700 3.85 0.01032 9.530 4.36 0.01036 8.490 4.94 0.010401 7.580
7.81 8.81 9.82 10.80 11.90 12.90
90.4 0.0178 0.1975 91.2 0.0200!,0.1974 92.0 0.0222 0.1973 92.8 0.0243 0.1971 93.7 0.0264 0.1970| 94.5 0.0286 0.1969
93.9 0.2049] 94.7 0.2047
97.4 0.2120 98.2 0.2117
95.5 0.2045 99.0 0.2114 96.3 0.2043 99.8 0.2111 97.2 0.2041 100.7 0.2109
98.0 0.2039 101.5 0.2107
30 35 40 45 50
5.57 0.0104S 6.27 0.01049 7.03 0.01053 7.88 0.01057 8.79 0.01062
6.770 6.080
5.460 4.920 4.440
13.90 14.90 16.00 17.00 18.10
95.3 96.1
96.8 97.6 98.4
0.0307 0.1969 0.0328 0.1968 0.0349 0.1968 0.0370 0.1967 0.0391 0.1967
98.8 99.6 100.3
101.1 101.9
0.2038 0.2037
0.2036
0.2035 0.2034
102.3 103.1
103.8 104.6 105.4
0.2105 0.2103
0.2101 0.2099 0.2098
55 60 65 70 75
9.80 0.01066 10.90 0.01071 12.10 0.01076 13.40 0.01081 14.80 0.01086
4.020 3.640 3.300
3.000
2.740
19.10 20.20 21.30 22.40 23.50
99.2 0.0412 0.1967 100.0 0.0432 0.1967 100.8 0.0453 0.1967 101.5 0.0473 0.1967 102.2 0.0493 0.1967
102.7 0.2033 103.5 0.2033 104.3 0.2032 105.0 0.2032 105.7 0.2031
106.2 0.2097 107.0 0.2096 107.8 0.2094 108.5 0.2093 109.2 0.2092
85 90 95
100 105
16.30 0.01091 17.90 0.01096 19.70 0.01101 21.60 0.01106 23.60 0.01111
25.90 0.01116
2.500 2.280 2.090 1.918 1.761
1.620
24.50 25.60 26.70 27.80 28.90
30.10
102.9
103.6 104.4 105.1
105.7 106.4
0.0513 0.1966 0.0533 0.1966 0.0553 0.1966 0.0573 0.1966 0.0593 0.1965 0.0613 0.1965
106.4 107.1
107.9 108.6 109.2 109.9
0.2030 0.2029
0.2028 0.2028 0.2027 0.2026
109.9 110.6 111.4 112.1
112.7 113.4
0.2090 0.2089 0.2088 0.2087
0.2085 0.2084
Table 6. Properties op Water .
.Sat .Temp
P
PAressas,..
Lb per
.SqIn
Volume
Liquid
Vapor
+52Heat Content and Enteoft Taken From
F
Heat Content Liquid Vapor
Entropy liquid Vapor
50 F Superheat. 100 F Superheat Ht. Ct. Entropy hlcl Entropy
32
35 40 45 50
0.0887 0.01602 3296.0 0.1000 0.01602 2941.0 0.1217 0.01602 2441.0 0.1475 0.01602 2034.0 0.1780 0.01602 1702.0
0.00 3.02 8.05 13.07 18.08
1073.0 1074.4
0.0000 0.0062
2.1826 2.1724
1096.9 1098.3
2.2277 2.2172
1120.8 1122.2
2.2688 2.2581
1076.8 1079.2
1081.5
0.0163 0.0262
0.0361
2.1555
2.1390 2.1230
1100.6 1102.9
1105.2
2.2000 2.1832
2.1667
1124.5 1126.7
1129.0
2.2406 2.2234
2.2066
55 60 65 70 75
0.2140 0.01603 1430.0 0.2561 0.01603 1206.0 0.3054 0.01604 1021.0 0.3628 0.01605 868.0 0.4295 0.01606 740.0
23.08 28.08 33.08 38.07
43.06
1083.9 1086.2 1088.6 1090.9 1093.2
0.0459 0.0556 0.0652 0.0746 0.0840
2.1073
2.0920 2.0771
2.0625 2.0483
1107.5 1109.8 1112.2
1114.5 1116.7
2.1506 2.1349
2.1196 2.1046 2.0900
1131.3
1133.5 1135.8 1138.1 1140.3
2.1902 2.1742
2.1585 2.1432
2.1283
so
85 90 95
100 105
0.507 0.596
0.698 0.815 0.949
1.101
0.01607 0.01609 0.01610 0.01612 0.01613
0.01615
632.9 543.3 467.9 404.2 350.3
304.4
48.05 53.04 58.03 63.01 68.00
72.98
1095.5 0.0933 2.0344 1119.0 2.0758 1142.5 2.1138
1097.8 0.1025 2.0208 1121.2 2.0619 1144.7 2.0996
1100.0 0.1116 2.0075 1123.4 2.0483 1146.8 2.0857
1102.3 1104.6
0.1206 0.1296
1.9946 1.9819
1125.6 1127.9
2.0350 2.0220
1148.9 1151.1
2.0721 2.0588
1106.8 0.1384 1.9695 1130.2 2.0093 1153.2 2.0458
For properties of steam at high temperatures, see Table S. Chapter I.
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CHAPTER 24. REFRIGERATION
The evaporator is usually constructed as an integral part of the centrif ugal type condensing unit, to chill water which is then circulated to the air conditioning system. This is done because it would not be economical to pipe these large volumes of refrigerant any distance.
Centrifugal compressors like reciprocating compressors can be divided into two general types, open and enclosed. In general, the open type compressor is geared to the driving mechanism, and operates at higher speed than the driving motor or turbine. A modern completely enclosed direct-driven, centrifugal compressor is illustrated in Fig. 2.
The compressor capacity can be varied by controlling the condensing pressure. This is accomplished by regulating the quantity and tem perature of the condenser cooling water. The capacity falls off with increasing condensing pressure. Centrifugal compressors are seldom
2 nd. stage compressor
Condenser
Fig. 2. Enclosed Type Centrifugal Condensing Unit
built for less than 50 tons capacity, since it is not practical to make impellers which pump much less than the volume of refrigerant required for this tonnage.
The steam jet type of compressor, under certain circumstances, is desirable for use in air conditioning. Steam supplies directly the power used for compressing the refrigerant, thus eliminating the losses connected with other methods of supplying energy. As the compression ratio between the evaporator and condenser under normal circumstances is large, the mechanical efficiency of the equipment is somewhat lower than that of the positive mechanical type compressor. The condensing water requirements are considerably greater, as both the refrigerant and the impelling steam must be condensed.
The steam jet system functions on the principle that water under high vacuum will vaporize at low temperatures. Steam jet boosters or com pressors of the type commonly used in power plants for various processes will produce the necessary low absolute pressure to cause evaporation of the water.
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